Wednesday, July 23, 2008
Thank You
Thank you, Professor Frolich. I thoroughly enjoyed this course and feel that I learned a great deal. Best wishes to you!
Final Self-Evaluation
REGARDING YOUR OWN PERFORMANCE
1. What were the three aspects of the assignments I've submitted that I am most proud of? The compendium reviews that I spent a great deal of time on, the quizzes that I improved on and finally received a 20/20 on one... :) ... and the labs.
2. What two aspects of my submitted assignments do I believe could have used some improvement? I'm not sure if I did the final lab completely right. I was getting a little tripped up on the last part of it, when I had to comment about how we've co-evolved.
3. What do I believe my overall grade should be for this unit? A
4. How could I perform better in the next unit? There is no next unit! :(
REGARDING THE UNIT (adapted from Stephen Brookfield, University of St. Thomas "Critical Incident Questionnaire")
At what moment during this unit did you feel most engaged with the course? The online labs. I love the hands on experiments.
At what moment unit did you feel most distanced from the course? Probably during the final lab. This was new to me, and I felt like I was a bit unsure of what I was doing. Also, sometimes, I had a hard time distinguishing what type of interaction it was.
What action that anyone (teacher or student) took during this unit that find most affirming and helpful? Other students asking and answering questions on the NING network. I love that.
What action that anyone (teacher or student) took during this unit did you find most puzzling or confusing? None.
What about this unit surprised you the most? (This could be something about your own reactions to the course, something that someone did, or anything else that occurs to you.)
The final lab was much easier than the other three. A very pleasant surprise!
1. What were the three aspects of the assignments I've submitted that I am most proud of? The compendium reviews that I spent a great deal of time on, the quizzes that I improved on and finally received a 20/20 on one... :) ... and the labs.
2. What two aspects of my submitted assignments do I believe could have used some improvement? I'm not sure if I did the final lab completely right. I was getting a little tripped up on the last part of it, when I had to comment about how we've co-evolved.
3. What do I believe my overall grade should be for this unit? A
4. How could I perform better in the next unit? There is no next unit! :(
REGARDING THE UNIT (adapted from Stephen Brookfield, University of St. Thomas "Critical Incident Questionnaire")
At what moment during this unit did you feel most engaged with the course? The online labs. I love the hands on experiments.
At what moment unit did you feel most distanced from the course? Probably during the final lab. This was new to me, and I felt like I was a bit unsure of what I was doing. Also, sometimes, I had a hard time distinguishing what type of interaction it was.
What action that anyone (teacher or student) took during this unit that find most affirming and helpful? Other students asking and answering questions on the NING network. I love that.
What action that anyone (teacher or student) took during this unit did you find most puzzling or confusing? None.
What about this unit surprised you the most? (This could be something about your own reactions to the course, something that someone did, or anything else that occurs to you.)
The final lab was much easier than the other three. A very pleasant surprise!
Unit 4 Lab Project: List of Species
Beetle
Yellojacket
Staphylococcus Epidermidis
Spider Mites
Moth
Mosquito
Iceberg Lettuce Field
Housefly
Dust Mite
Black Widow
Definition of Domestication: A population of animals or plants, through a process of selection, that becomes accustomed to human provision and control, or care.
1.
- Common Name: Dog
- Scientific Name: Canis Lupus Familiarus
- Interaction: Symbiotic. Our family benefits from this relationship because we receive love, entertainment, and protection from our dogs. The dogs benefit because they receive all of this from us, plus food, water, etc.
- Domesticated.
- We have been co-evolving ever since man decided to domesticate the wild dog. They have assisted us in hunting, protection, etc., and we have come to depend on them for these things.
2.
- Common Name: Cat
- Scientific Name: Felius Domesticus
- Interaction: Symbiotic. Our family benefits from this relationship because she is sweet and loving, and has been known to catch a mouse or two. In fact, some humans "use" cats just for that purpose: hunting of rodents in barns, etc. The cat benefits because it has a warm, safe environment, and we provide it with food, water, and love.
- Humans have co-evolved with this species in the same way as with dogs.
3.
- Common Name: Dust Mite
- Scientific Name: North American Dermatophagoides Farinae
- Interaction: Parasitic. Dust mites feed on dead skin cells of humans. At first, I thought that maybe that benefited humans in the fact that they are, in a way, cleaning up our beds, etc. from dead skin cells. But I figure that we can easily throw a sheet in the washer, vacuum, dust, etc., so we don't need them to do that and the effect of them doing it is surely very minimal. I learned that dust mites are the most common cause of allergies, so they are harmful to humans.
- Not domesticated. Since we can't see them with the naked eye, our interaction with them is "blind".
- Humans have co-evolved with them because there is really nothing we can do to totally eliminate them. Yes, you can vacuum everyday, but you can't get them all. Basically, we hardly notice that they're there, and even if we have allergies, we medicate ourselves, and our interaction with them is unchanged.
4.
- Common Name: Willow Tree
- Scientific Name: Salix Salicaceae
- Interaction: Symbiotic. The tree benefits because it depends on us to water it, fertilize it, and take care of it. (Especially here in the desert.) We benefit because we can enjoy its beauty and shade.
- Domesticated. As I said, here in the desert, the tree has become accustomed to humans caring for it and depends on them. Also, humans "farm" trees.
- We co-evolve with them very easily; we enjoy them and they need us. They also help the environment through photosynthesis. Unfortunately, we sometimes cut too many down, but they keep growing (after we plant them), and we co-evolve.
5.
- Common Name: Red Ant
- Scientific Name: Formicidae Solenopsis
- Interaction: Parasitic. I am unaware of any benefits to other species from red ants. Contrary, other species are harmed by the red ant. Humans can be stung, and they kill crickets and plants to eat.
- Not domesticated. We do not come into contact (voluntarily) with red ants, and they are not accustomed to humans.
- Humans don't always co-evolve with this species well. Many times, we have pest control come out and spray the ant hills in order to avoid our pets or children getting stung by the multiple numbers of ants in a colony. We try to avoid them.
6.
- Common Name: Whiptail Lizard
- Scientific Name: Teiidae
- Interaction: Commensal. I think that we benefit, because we see them outside in our yard all the time and my kids love watching them and admiring them. The lizard is unharmed.
- Not domesticated. They are not accustomed to humans.
- We co-evolve by mostly ignoring each other. The lizards around our house are skittish, yet they remain right around the door, in the yard, etc. I do not think that they are accustomed to us, yet we can get close enough to them at times to admire them from close range, so they are obviously not harmed by us, either.
7.
- Common Name: Peach
- Scientific Name: Prunus Persica
- Interaction: Mutualistic. Peach trees are planted and cared for by humans, but I believe we benefit more, because we get to enjoy them when we eat them.
- Domesticated. Farmers plant and raise the trees, then sell the fruit.
- We co-evolve in that manner: purchase the seeds, baby trees, plant them, nourish them, pick the fruit, and sell it. However, we can grow them in places outside of their natural environment, so we co-evolve together nicely.
8.
- Common Name: Housefly
- Scientific Name: Musca Domestica
- Interaction: Hmmm... this one is more confusing. I suppose humans benefit because flies decompose certain nasty dead and decaying materials. Yet, they can make us ill (they carry over 100 pathogens), and are horribly annoying. So, we usually swat them. They definitely do not benefit from humans. I think this relationship would be parasitic, b/c we benefit from their ability to decompose, and they are often harmed by humans.
- Domesticated, in a way, but undomesticated, too. They have become accustomed to humans, to a degree, but we do not control or care for them. Unless, of course, "control" can be understood as pest control, in that we eliminate them when we can.
9.
- Common Name: Bird
- Scientific Name: Aves
- Interaction: Mostly commensal, but can be symbiotic. We benefit from their beauty, their song, the fact that they eat insects, etc. Most of the time, the bird is unharmed. Sometimes, however, they benefit too, (symbiotic), like when we provide bird baths and bird seed for them.
- Not domesticated. They are mainly wild (the ones I come in contact with, anyhow.) However, some people own them as pets, and those would obviously be domesticated.
- We co-evolve with them naturally. Since they are airborn, most people do not come into direct contact with them.
10.
- Common Name: Southern Black Widow
- Scientific Name: Latrodectus Mactans
- Interaction: Well, if you can appreciate that they feed on insects, you could say that that is a benefit to the human species. This relationship would be commensal. However, their venom is very potent, and they can be very harmful to humans. They do not benefit from humans at all, other than indirectly, when they come live in your house and get shelter without you knowing it. So, it could be considered parasitic, in this respect: they receive shelter, and we get bit.
- We co-evolve with them by being ignorant of their existence, and when we are made aware of it, we usually squish them.
11.
- Common Name: Scorpion
- Scientific Name: Scorpiones Arachnida
- Interaction: Again, scorpions eat insects, so that could be considered beneficial to humans. Scorpions do not benefit at all from humans. In this respect, the relationship would be considered commensal. However, I would rather see pretty much any insect in the world before a scorpion, and I got stung by one just last week. So in this scenario, I don't think humans benefit from them at all, but they don't benefit either. What kind of relationship is that? :)
- We co-evolve by avoiding them as much as possible, and they co-evolve with us by defending themselves.
12.
- Common Name: Cricket
- Scientific Name: Gryllidae
- Interaction: Commensal: Crickets are omnivores and scavengers feeding on organic materials, as well as decaying plant material, fungi, and some seedling plants. In this way, humans benefit from them, but I can't see any way they benefit from us.
- Not domesticated.
- We co-evolve by mostly ignoring each other. (Except when they're chirping outside your window driving you nuts and you have to go scare them away.)
13.
- Common Name: Mosquito
- Scientific Name: Culicidae
- Interaction: Parasitic. They drink our blood, and make us susceptible to diseases.
- Not domesticated.
- We co-evolve by using bug spray and smacking them when we see them.
14.
- Common Name: Strawberries
- Scientific Name: Fragaria Ananassa
- Interaction: Symbiotic. We plant them and take care of them (at least, the farmers who sell them), and then we get to enjoy them by eating them.
- Both domesticated and not domesticated (some are still wild).
- We co-evolve by growing them, eating them, and then re-growing them.
15.
- Common Name: S. Epidermis (Found on skin and in nasal passages.)
- Scientific Name: Staphylococcus Epidermidis
- Interaction: Parasitic. We receive no benefits from this bacteria. It lives on our skin, and if the skin is punctured, CAN cause disease.
- Not domesticated.
- Humans have always co-evolved with this bacteria. It is invisible to us and does not bother us, unless a wound becomes infected with it, and then it is treated with antibiotics.
16.
- Common Name: Spider Mites
- Scientific Name: Tetranychus Urticae (Plant feeding mite found in dry areas.)
- Interaction: Parasitic. They can cause significant damage to plants because they puncture the plant's cells for food. The plant (nor humans) receive any benefit from them.
- Not domesticated.
- We co-evolve without really noticing each other. They are minuscule. If we were to interact with them at all, it would be to eliminate them with some sort of pesticide.
17.
- Common Name: Rose
- Scientific Name: Rosa Rosaceae
- Interaction: Symbiotic. We plant them, nurture them, water them, feed them, and we enjoy their beauty and scent.
- Domesticated.
- We co-evolve in the same manner as described above under "Interaction".
18.
- Common Name: Yellojwacket
- Scientific Name: Dolichovespula Arenaria
- Interaction: Symbiotic. Humans benefit minimally because they are MINOR pollinators. They only benefit from humans when humans plant flowers / bushes for them to pollinate. However, some might argue that the relationship is parasitic, in the sense that they are only minor pollinators, and can sting humans. They can even cause death if a whole bunch of them swarm a human.
- Not domesticated.
- We co-evolve through avoidance, both ways. We avoid them so we won't get stung. They usually avoid people because there is no benefit for them to interact with us.
19.
- Common Name: Moth
- Scientific Name: Insecta Lepidoptera
- Interaction: Parasitic, though it depends on what kind of moth. Most moths (or their larvae) are extremely destructive to trees, fruit trees, and forests because they feed on them. So, they receive nourishment, but they can kill the trees. However, if you were specifically talking about the silkworm (larvae of a certain kind of moth), you would have to say symbiotic, because humans benefit from their silk.
- Not domesticated.
- We co-evolve (again) by ignoring each other. Humans mostly find them a nuisance, but they really pay no attention to us at all.
20.
- Common Name: Lettuce (in salad)
- Scientific Name: Lactuca Sativa
- Interaction: Mutualism. We plant, nourish and grow it. We also then eat it as a form of nourishment, which seems like the better deal of the two.
- Domesticated.
- Co-evolve by taking care of it and then consuming it.
21.
- Common Name: Ladybug
- Scientific Name: Coccinellidae
- Interaction: Commensal. Humans benefit, because they feed on small insects and they are fun and "friendly" for children to interact with. They do not benefit from us, though.
- Not domesticated.
- They don't bother us, and we don't bother them! :)
22.
- Common Name: Coffee
- Scientific Name: Coffea Canephora
- Interaction: Symbiotic. It is planted and grown commercially, and then humans enjoy it in liquid form.
- Domesticated.
- We cultivate it, sell it, and drink it.
23.
- Common Name: Beetle
- Scientific Name: Coleoptera
- Interaction: Commensal. We benefit from them because they break down animal and plant debris. I don't think they benefit from us, but we do not harm them, either. (Generally speaking.)
- Not domesticated.
- We pretty much ignore each other.
Tuesday, July 22, 2008
Ethical Issues Essay: World Resource Use
World Population Total
World Population Growth Rate
It is abundantly clear that, worldwide, we are in danger of exhausting our natural resources. Our nonrenewable resources, those limited in supply, consist of things like land, fossil fuels and minerals. It seems that, eventually, it is inevitable that these resources will run out completely. Even our renewable resources (water, food, certain forms of energy) are in danger, because consumption is threatening to overcome the rate of replenishment. An entirely different concern is directly related to the problem of the exhaustion of our natural resources: pollution and loss of biodiversity, habitats, etc. These issues should be of great concern to all of us.
Initially, people thought that fertility rates alone were the main contributors to the loss of our resources. Obviously, they were right, to an extent. High fertility rates equal population booms, which equals strain on resources. However, the theory that this is the only factor causing this major strain is very clearly wrong. Consider China, the world's most populous country. When they realized how their population was effecting their consumption of resources, they decided to impose a 0 population growth plan, that limited each couple to only 2 children. Because of this, the country has decreased their fertility rate. Why, then, has their resource use (especially in respect to energy) continued to soar? First, while it is true that couples were having less children, the fact is that there were MORE couples to have children, due to previous population booms. The idea that the two children simply replaced the parents, and there was therefore no growth, was a fallacy. This is because each couples children would then go and have children themselves. Now, the family unit consisted of the couple, their two children, and the two children each of their two children. Obviously, this continues the population growth. To further explore this idea, consider the following fact: birth rates have dropped to nearly half of what they were in 1950, worldwide. (See above chart: World Population Growth Rate.) However, the world population will continue to increase. (See above chart: World Population Total.) So, even when people are limited in the amount of children they have, populations continue to grow, and the more people there are, the greater the strain on resources.
However, there are other factors that contribute to this strain. When it comes to energy consumption, "When a North American couple stops at two children, it is the equivalent of an East Indian couple stopping at 60, or an Ethiopian couple at 600." Wow. That is a startling statistic! This makes it very clear that economic development has an even greater impact on the overconsumption of our resources than population does. How is this even possible? One only has to consider the vast differences between the "comfortable" life we experience as Americans, in comparison to the way people struggle in LDCs. I can't even imagine living somewhere where my child was in constant danger of dying due to things like limitations of healthy foods, water contamination, and disease. In fact, the mere thought of it is horrifying to me. Instead, my four year old has everything she could possibly need. She can eat as much as she wants to fill her tummy, every single day. She has the luxury of electricity: air-conditioning, fans, lighting, music, movies, television, video games, computer, etc. Her water is filtered and clean, and again, she can drink as much as she wants of it every single day. She can take her nightly bath, and go to bed clean and comfortable. She receives vaccinations to keep her safe from the diseases that could otherwise kill her. When I think about it in this way, I am reminded of how lucky she is... and I am, to live in a place where all of this is routine. So, it is alien and heartbreaking to me to think of the way people in LDCs must live. However, I also realize how unfair it is for my children to have all of these luxuries when other children struggle so, and in turn, be partially responsible for the scary situation we are in regarding the exploitation of our resources. Is it necessary for us as a family to use the amount of energy we do every single day lighting our homes, watching our tvs, using our computers and video games for pure entertainment, etc? Absolutely not. And yet, because this is the life we are accustomed to, I can hardly even imagine living without our television for a week! "The per capita energy consumption rate in the U.S. is 11000 W, the approximate rate of energy consumption of a 30,000 Kg primate." So sad, but believable, based on my above commentary.
So, the answer the question "What else strains our resources?", besides population? Over-consumption. The overuse of our resources because we have become accustomed to a certain lifestyle, as a community. Basically, we are a spoiled Nation. We have become accustomed to driving everywhere, and having "unlimited" (or so we thought) access to things like electricity and water. Should we stop worrying altogether about population growth? Absolutely not; there is no doubt that it still contributes to the problem. But it is in no way the only problem. In all honesty, the "Go Green" movement is a wonderful start and has been a long time in coming, but until people begin to realize the truly devastating nature of our current situation when it comes to the exhausting of our resources, many people will not take it seriously, and the problems we are seeing now will only get worse for future populations.
Monday, July 21, 2008
Human Populations Demographics Online Lab
World Vs. High Fertility Rate Country (Ethiopia)
World Vs. Low Fertility Rate Country (Barbados)
Answer the following questions:
1. What was your high fertility rate country and what was its fertility rate? My high fertility rate country was Ethiopia. Its fertility rate was 6.90 children.
2. What was your low fertility rate country and what was its fertility rate? My low fertility rate country was Barbados. Its fertility rate was 1.80 children.
3. The initial demographic "shape" of your high fertility rate country should have been a pyramid, with high population in young age groups. Explain why high fertility rate results in a high percentage of young people in the population. How does this affect future population growth? If a country has a high fertility rate, it means that women in their reproductive years (approximately 20-40) are producing a large number of offspring. The more women reproducing, the more young people there would be in the population. As the young population grows with more births, it is understandable that the population of young people could surpass the population of old. Future population growth would be affected because the more young people you have in a population, the more potential for growth. There would be more children who will reach reproductive years and reproduce, so the population will continue to increase.
4. Your low fertility rate country might have had a more oval-shaped curve with high population in middle age groups. This is especially exaggerated if the fertility rate is below 2.00. Explain why low fertility rate leads to lots of middle-aged people. Low fertility rate means that there are less people of reproductive age who are producing. In other words, if you have a group of 50 women who are of reproductive age, but only 10 of them reproduce, you would obviously have more middle-aged people than young, because not many are reproducing. The older generation will die of natural causes / old age, so the "largest" population would be the middle-aged people.
5. Write ten adjectives or descriptive phrases for what you might expect life, people's attitudes, conditions on the streets, etc. will be like in each of those situations. Imagine a situation with lots of middle-aged and older people in the population and write ten quick "brain-storm" descriptors for you think it would be like (Prescott, Arizona?). Then do the same for a situation with lots of children in the population.
Middle Ages / Older Population:
1. Wise / Educated
2. Responsible
3. Quiet
4. Organized
5. Comfortable
6. Clean
7. Sad (Children bring joy!)
8. Efficient
9. Conservative
10. Lacking in energy
Children / Young Population:
1. Energetic
2. Boisterous
3. Happy- Family Units
4. Carefree
5. Joyous
6. Disorganized
7. Loud
8. Supportive
9. More diverse
10. More culturally accepting
Compendium Review Chapter 24- Pictures
Species Extinction by State
Biodiversity Loss
Wind Farm
Global Warming
Desertification Risk
(World Map- Population Density)
Compendium Review Chapter 24
I. Human Population Growth
II. Human Use of Resources and Pollution
III. Biodiversity
IV. Working Toward a Sustainable Society
I. Human Population Growth
A. Current world population: Approx. 7 billion people.
- Exponential Growth: Increase of growth by a great deal.
- Growth Rate: Determined by considering the difference between the number of persons born per year and the number who die per year. Rates are recorded per 1000 people.
- Biotic Potential: Maximum growth rate under ideal conditions.
- Growth declines due to factors such as food and space.
- Carrying Capacity: Maximum population that the environment can support for an indefinite period.
B. MDCs Versus the LDCs
1b. MDCs: More Developed Countries: (countries like N American and Europe.) MDCs are those in which populatin growth is modest and the people enjoy a good standard of living.
- 1850-1950: Big population increases due to development of modern medicine and improvements in public health and socioeconomic conditions. Since then, the decline in death rate was folllowed by a decline in birthrate, so there has only been modest growth since 1950.
- Population by 2050 is expected to be about 1.2 billion.
2b. LDCs: Less-developed countries: (Africa, Asia)
- Death rate declined steeply w/ modern medicine, but birthrate remained high.
- Women in sub-Saharan Africa average 5 children each.
- Population by 2050 is expected to be about 8 billion.
- Asia is the "worst", in that they are expected to experience acute water scarcity, loss of biodiversity, and more urban pollution. 12 of 15 most polluted cities are located in Asia.
(Insert World Map / Population Density picture / mapsofworld.com / http://mapsofworld.com/world-population-density.htm)
C. Comparing Age Structure: Populations have 3 age groups: pre-reproductve, reproductive, and postreproductive.
- Replacement Reproduction: The idea of couples limiting themselves to 2 children equalling zero population grwoth.
- Untrue, beccause since more young women are entering the reproductive years than older women leaving them, the population continues to increase. (Mader 512-513)
II. Human Use of Resources and Pollution
A. Resources used the most by humans: land, water, food, energy, and minerals.
1a. Nonrenewable Resources: Limited in supply. Land, fossil fuels, and minerals is finite and can be exhausted.
- Renewable Resources: Capable of being naturally replenished. Water, certain forms of energy, plants, animals, etc. can be replenished.
B. Pollution: Side effect of resource consumption. Any alteration of the environment in an undesirable way.
- Often caused by human activity. Effect is proportional to the size of the population.
1b. Land: Worldwide, there are approx. 83 persons per square mile of all available land.
- Land is alse required for agriculature, power plants, highways, other buildings (hospitals), etc., in addition to homes.
2b. Beaches and Human Habitation: Approx 40% of world population lives within 60 miles of a coastline, and is expected to increase.
- Causes beach erosion, loss of habitat for marine organisms, and loss of buffer zone for storms.
- Particularly susceptible to pollution.
3b. Semiarid Lands and Human Habitation: 40% of Earth's lands are deserts.
- Desertification: The conversion of semiarid land to desertlike conditions.
- Begins w/ overgrazing of land. Soil can't hold rainwater, so it runs off instead of nourishing life. Any vegetation is removed by humans, and results in a lifeless desert.
(Insert Desertification Risk picture / www.sou.edu http://www.sou.edu/Geography/JONES/GEOG111.112/atlas/atlas.htm)
4b. Tropical Rain Forest and Human Habitation:
- Deforestation: Removal of trees.
- People are settling tropical rain forests, like the Amazon. This land then becomes subject to desertification.
- Land quickly loses its fertility because most of the nutrients are in trees or other vegetation.
- Loss of biodiversity.
C. Water: Worldwide, 70% of all freshwater is used to irrigate crops.
- In MDCs, more water is usde for bathing, flushing toilets, and watering lawns than for drinking and cooking.
- humans increase the supply of freshwater by damming rivers and withdrawing water from aquifers.
1c. Dams: Worlwide, 45,000 dams catch 14% of all precipitation runoff, provide water for up to 40% of irrigated land, and provide approx. 65 countries w/ more than 1/2 of their electricity.
- Lots of water loss due to evaporatin and seepage into underlying rock beds.
- Salt left behind by evap. and runoff increases alinity and can make a river's water unusable.
- Hold back less h2n w/ sediment buildup.
2c. Aquifers: Reservoirs found just below or as much as 1km below surface.
- Causes ground-water depletion.
- Consequences: Causing land subsidence, a settling of soil as it dries out. Causes surface of ground to drop. Subsidence causes damage to canals, buildings, and underground pipes.
- Can cause sinkholes: Underground collapsing of cavern when water no longer holds up roof.
- Saltwater Intrusion: As water is withdrawn, water table can lower to the point that seawater backs up into streams and aquifers, which reduces supply of freshwater.
3c. Conservation of Water:
- By 2025, approx. 2/3 of world's population may be living in countries facing seriuos water shortages.
- Possible solutions: Planting drought and salt-tolerant crops, using drip irrigation, re-use of water, and adopting conservation measures. (Mader 514-515)
D. Food: Comes from growing crops, raising animals, and fishing the seas.
1d. Harmful practices of farming methods:
- Monoculture: planting of only a few genetic varieties means a single type of parasite can cause total devestation.
- Heavy use of ferilizers, pesticides, and herbicides. (Causing water pollution, decreased soil fertility, development of cancer.)
- Agricultural runoff: Causes chemicals to enter our water supply.
- Generous irrigation: Too much water is extracted from aquifers.
- Excessive fuel consumption.
2d. Soil Loss and Degredation: Land that is good for farming and grazing animals is being degraded worlwide.
- Soil erosion causes loss of topsoil, causing desertification. Farmland is unproductive.
- U.S. and Canada have the highest rates of soil erosion in the world.
- Salinization: Accumulation of mineral salts due to evaporation of excess irrigation water. Makes land unsuitable for growing crops.
3d. Green Revolutions: Dramatic increase in yield of crops in LDSs due to introduction of new varieites of crops. Still require high levels of fertilizer, water, and pesticides, so they cause the same problem as modern farming methods.
4d. Genetic Engineering: Can produce transgenic plants resistant to insects and herbicides. Soil erosion is minimized.
5d. Domestic Livestock: 2/3 of cropland is devoted to producing livestock feed. Therefore, raising livestock accouts for much of the pollution associated with farming.
- Problems: waste, water use for washing livestock, etc. (Mader 516-519)
E. Energy:
1e. Nonrenewable Sources: Nuclear power (approx. 6% of world's energy supply) and fossil fuels (approx. 75%).
- Nuclear power: Not used very much because of nuclear power dangers and radioactive wastes.
- Fossil Fuels: Oil, natural gas, and coal. Derived from compressed remains of ploants and animal that died many thousands of years ago. U.S. is only 5% of world's population, yet it uses more than half of the fossil fuel energy supply! Pollutants are released into the air as it burns.
2e. Fossil Fuels and Global Climate Change:
- Burning of fossil fuels and burning of forests has caused increase in carbon dioxide in the atmosphere.
- Human activities cause emission of other gases, too, such as methane. These are greenhouse gases, because they allow solar radiation to pass through but hinder the escape of infrared heat back into space.
- Global Warming: Earth may warm to temps never before experienced by living things. If this happens, glaciers will melt, sea levels will rise, and coastal cities could be threatened. Would endanger coral reefs, present assmeblage of species in ecosystems will be disrupted as species migrate north for cooler weather. Loss of species unable to migrate.
(Insert Global Warming picture / global.mitsubishielectric.com / http://global.mitsubishielectric.com/bu/solar/environment/main.html)
3e. Renewable Energy Sources: Hydropower, geothermal, wind, and solar.
- Hydropower: Converts energy of falling water into electricity. Approx. 10% of electric power generated in US, and almost 98% of total renewable energy used.
- Geothermal Energy: Uranium, thorium, radium, and plutonium undergo radioactive decay below Earth's surface and heat the surrounding rocks. When they are in contact w/ water, it heats water. Can be piped up to surface for use.
- Wind Power: Space needed for wind farms that produce electricity is comparable to amount of land required by a coal-fired power plant or solar energy system. Expected to increase use in future.
(Insert Wind Farm picture / www.ronsaari.com / http://www.ronsaari.com/stockImages/windmills/WindFarmPalmSpringsCA.php)
- Energy and the Solar-Hydrogen Revolution: Solar energy must be collected, converted, and stored. Can be used for passive-solar heating of houses, and heat can be sotred in water tanks, rocks, bricks, etc.
- Photovoltaic (solar) cell: A wafer of electron-emitting metal is in contact with another metal that collects the eletrons and passes them along into wires in a steady stream. These cells can be placed on roofs to generate electricity. Can be used to create hydrogen fuel, to be used in future cars. (Mader 520-522)
F. Minerals: Nonrenewable raw materials in Earth's crust that can be extracted. Includes fossil fuels, nonmetallic raw materials, such as sand, gravel, and phophate; and metals, such as aluminum copper, iron, lead, and gold.
- Heavy metals are dangerous to humans: lead, mercury, arsenic, cadmium, tin, chromium, zinc, and copper. Used in electronics, medicines, paints, etc. Inhibit vital enzymes in body.
- Strip / surface mining: One of greatest threats to maintenance of ecosystem and biodiversity. Rain washes toxic waste deposits into streams and rivers.
1f. Hazardous Wastes: Nine most common: heavy metals, synthetic organic compounds, benzene, polychlorinated biphenyls, and chloroform.
- Chlorofluorocarbons: Type of halogenated hydrocarbon in which both chlorine and flourine atoms replace some of the hydrogen atoms. Thin ozone shield, which is essentail for protection of utraviolet radiation.
- Biological Magnification: Wastes that enter and accumulate in the fat or organisms, ans since they are not excreted, they become more and more concentrated as they pass along a food chain. (Mader 522-523)
III. Biodiversity
A. Biodiversity is the variety of life on Earth, described in terms of the number of different species.
- We are in biodiversity crisis: Number of extinctions expected to occur in the near future is unparallel in the history of the Earth.
B. Loss of Biodiversity is due to all of the following:
- Habitat Loss: Human occupation and expansion.
- Alien Species (Exotics): Nonnative members of an ecosystem. Humans introduce them to ecosystems due to colonization, horticulture, and agriculture, and accidental transport. Some are invasive, and crowd out native species.
- Pollution: Acid deposition (weakens trees), global warming (loss of habitat, etc.), ozone depletion (CFCs), and synthetic organic chemicals.
- Overexploitation: Too many individuals are taken from a wild population so it is reduced in number. ie. exotic pets. (Poaching, overfishing, etc.)
- Disease: Exposure to domestic animals and their pathogens occur when humans encroach on wildlife habitats.
(Insert Biodiversity Loss picture / www.greenfacts.org http://www.greenfacts.org/en/desertification/l-3/7-climate-change-biodiversity-loss.htm)
C. Direct Value of Biodiversity: Direct value of wildlife is related to their medicianl value, agricultural value,and consumptive use value.
1c. Medicinal Value: Potent medicines are dervied from plants, fungus, some animals (ie horseshoe crab) and certain types of bacteria.
2c. Agricultural Value: Crops are dervied from wild plants that have been modified to be high producers. Biological pest control, bees pollinating plants, etc/
3c. Consumptive Use Value: Catching of fishes, crustatceans, and mammals. Products sold in marketplaces. Trees for wood, etc.
D. Indirect Value of Biodiversity: Services that are pervasive and not easily discernable.
- Waste Disposal: Decomposers break down dead organic matter and other types of wastes to inorganic nutrients that are used by the producers within ecosystems. If not for this service, Earth would be covered in waste. Some biological communities can break down and immobilize pollutants.
- Provision of freshwater: Water cycle supplies freshwater to terrestrial ecosystems. Provide us w/ fish and other food. "Sponge Effect": Forests soak up water and release it at a regular rate.
- Prevention of Soil Erosion: Intact ecosystems naturally retain soil and prevent soil erosion.
- Biogeochemical Cycles: Biodiversity within ecosystems contributes to the workings of the water, phophorus, nitrogen, carbon, and other biogeochemical cycles, which we depend on for freshwater.
- Regulation of Climate: Trees provide shade and reduce the need for fans and air conditioners. Forests ameliorate the climate because they take up carbon dioxide. Carbon dioxide has a significant impact on global warming, which is increased with deforestation.
- Ecotourism: Relaxing in the wild! :) (Mader 524-530)
IV. Working Toward a Sustainable Society
A. Sustainable Society: One that could always provide the same amount of goods and services for future generations as it does at present. Biodiversity would also be preserved.
1a. Today's Unsustainable Society: Population growth and excessive resource consumption stresses the environment, including worldwide pollution and the extnction of wildlife.
(Insert Species Extinction by State picture / www.unl.edu / http://www.unl.edu/nac/conservation/atlas/Map_Html/Biodiversity/National/Species_Extinctions/Species_extinctions.htm)
2a. Characteristics of a Sustainable Society:
- Makes use of only renewable solar energy.
- Materials cycle through the various populations back to the producer.
- Protection of natural ecosystmes.
- Efficiency (cars, etc.)
3a. Rural Sustainability:
- Emphasis on preservation: ecosystems, agricultural land, groves of fruit trees, etc. Possible steps: plant cover crops, multiuse farming, replenish soil nutrients, low flow or trickle irrigation, increase planting of cultivars, use precision farming, use integrated pest management, etc.
4a. Urban Sustainability:
- Sharing of resources. Possible steps: Energy-efficient transportation system, solar or geothermal energy, utilize green roofs, improve storm-water management, plant native species grasses, create greenbelts, etc.
B. Assessing Economic Well-Being and Quality of Life:
- Gross National Product: Measurement of the flow of money from consumers to businesses, in the form of goods and services purchased. (Total costs of manufacturing, production and srvices in the form of salaries, wages, mortgage and rent, interets and loans, taxes, and profit. Use value, option value, existence value, aesthetic value, cultural value, and scientific and educational value are all factors. (Mader 530-533)
Ok... So I'm not going to lie... I had a REALLY hard time fitting the last part of your powerpoint into chapter 24. I felt like I was reading the wrong chapter, or something. So, I'm including it here in the end:
In a community, relationships among species can be beneficial, damaging or neutral:
Symbiotic: mutually beneficial, both species benefit
Parasitic: one species benefits (“parasite”) and the other is harmed (“host”)
Commensal: One species benefits, the other is unharmed
Mutualism: both species benefit, like symbiosis, but it may appear one species has the advantage, but evolutionarily, over the long-term, both benefit
Predation: Usually considered parasitic, where the predator is the parasite, but can also be seen as mutualistic.
(Frolich PowerPoint Slide 26)
A. Relationships Among Species
- We do still have ecological relationships with “wild” species. Examples:
- Hunt mushrooms
- Create game reserves
- Create national parks
- Household and urban/rural “pests” (e.g. molds, sewer rats)
- Symbiotic micro-organisms (skin and mouth bacteria)
- Disease-causing micro-organisms
(Frolich PowerPoint Slide 26)
B. Our Relationships w/ Domesticated Species
- But mostly we have tight relationships with domesticated species. Basis for ecological relationship:
- Food and agriculture (by far most common—food crops and animals)
- Transportation (“beasts of burden”)
- Care and protection (pets)
- Laboratory study and production
(Frolich PowerPoint Slide 29)
II. Human Use of Resources and Pollution
III. Biodiversity
IV. Working Toward a Sustainable Society
I. Human Population Growth
A. Current world population: Approx. 7 billion people.
- Exponential Growth: Increase of growth by a great deal.
- Growth Rate: Determined by considering the difference between the number of persons born per year and the number who die per year. Rates are recorded per 1000 people.
- Biotic Potential: Maximum growth rate under ideal conditions.
- Growth declines due to factors such as food and space.
- Carrying Capacity: Maximum population that the environment can support for an indefinite period.
B. MDCs Versus the LDCs
1b. MDCs: More Developed Countries: (countries like N American and Europe.) MDCs are those in which populatin growth is modest and the people enjoy a good standard of living.
- 1850-1950: Big population increases due to development of modern medicine and improvements in public health and socioeconomic conditions. Since then, the decline in death rate was folllowed by a decline in birthrate, so there has only been modest growth since 1950.
- Population by 2050 is expected to be about 1.2 billion.
2b. LDCs: Less-developed countries: (Africa, Asia)
- Death rate declined steeply w/ modern medicine, but birthrate remained high.
- Women in sub-Saharan Africa average 5 children each.
- Population by 2050 is expected to be about 8 billion.
- Asia is the "worst", in that they are expected to experience acute water scarcity, loss of biodiversity, and more urban pollution. 12 of 15 most polluted cities are located in Asia.
(Insert World Map / Population Density picture / mapsofworld.com / http://mapsofworld.com/world-population-density.htm)
C. Comparing Age Structure: Populations have 3 age groups: pre-reproductve, reproductive, and postreproductive.
- Replacement Reproduction: The idea of couples limiting themselves to 2 children equalling zero population grwoth.
- Untrue, beccause since more young women are entering the reproductive years than older women leaving them, the population continues to increase. (Mader 512-513)
II. Human Use of Resources and Pollution
A. Resources used the most by humans: land, water, food, energy, and minerals.
1a. Nonrenewable Resources: Limited in supply. Land, fossil fuels, and minerals is finite and can be exhausted.
- Renewable Resources: Capable of being naturally replenished. Water, certain forms of energy, plants, animals, etc. can be replenished.
B. Pollution: Side effect of resource consumption. Any alteration of the environment in an undesirable way.
- Often caused by human activity. Effect is proportional to the size of the population.
1b. Land: Worldwide, there are approx. 83 persons per square mile of all available land.
- Land is alse required for agriculature, power plants, highways, other buildings (hospitals), etc., in addition to homes.
2b. Beaches and Human Habitation: Approx 40% of world population lives within 60 miles of a coastline, and is expected to increase.
- Causes beach erosion, loss of habitat for marine organisms, and loss of buffer zone for storms.
- Particularly susceptible to pollution.
3b. Semiarid Lands and Human Habitation: 40% of Earth's lands are deserts.
- Desertification: The conversion of semiarid land to desertlike conditions.
- Begins w/ overgrazing of land. Soil can't hold rainwater, so it runs off instead of nourishing life. Any vegetation is removed by humans, and results in a lifeless desert.
(Insert Desertification Risk picture / www.sou.edu http://www.sou.edu/Geography/JONES/GEOG111.112/atlas/atlas.htm)
4b. Tropical Rain Forest and Human Habitation:
- Deforestation: Removal of trees.
- People are settling tropical rain forests, like the Amazon. This land then becomes subject to desertification.
- Land quickly loses its fertility because most of the nutrients are in trees or other vegetation.
- Loss of biodiversity.
C. Water: Worldwide, 70% of all freshwater is used to irrigate crops.
- In MDCs, more water is usde for bathing, flushing toilets, and watering lawns than for drinking and cooking.
- humans increase the supply of freshwater by damming rivers and withdrawing water from aquifers.
1c. Dams: Worlwide, 45,000 dams catch 14% of all precipitation runoff, provide water for up to 40% of irrigated land, and provide approx. 65 countries w/ more than 1/2 of their electricity.
- Lots of water loss due to evaporatin and seepage into underlying rock beds.
- Salt left behind by evap. and runoff increases alinity and can make a river's water unusable.
- Hold back less h2n w/ sediment buildup.
2c. Aquifers: Reservoirs found just below or as much as 1km below surface.
- Causes ground-water depletion.
- Consequences: Causing land subsidence, a settling of soil as it dries out. Causes surface of ground to drop. Subsidence causes damage to canals, buildings, and underground pipes.
- Can cause sinkholes: Underground collapsing of cavern when water no longer holds up roof.
- Saltwater Intrusion: As water is withdrawn, water table can lower to the point that seawater backs up into streams and aquifers, which reduces supply of freshwater.
3c. Conservation of Water:
- By 2025, approx. 2/3 of world's population may be living in countries facing seriuos water shortages.
- Possible solutions: Planting drought and salt-tolerant crops, using drip irrigation, re-use of water, and adopting conservation measures. (Mader 514-515)
D. Food: Comes from growing crops, raising animals, and fishing the seas.
1d. Harmful practices of farming methods:
- Monoculture: planting of only a few genetic varieties means a single type of parasite can cause total devestation.
- Heavy use of ferilizers, pesticides, and herbicides. (Causing water pollution, decreased soil fertility, development of cancer.)
- Agricultural runoff: Causes chemicals to enter our water supply.
- Generous irrigation: Too much water is extracted from aquifers.
- Excessive fuel consumption.
2d. Soil Loss and Degredation: Land that is good for farming and grazing animals is being degraded worlwide.
- Soil erosion causes loss of topsoil, causing desertification. Farmland is unproductive.
- U.S. and Canada have the highest rates of soil erosion in the world.
- Salinization: Accumulation of mineral salts due to evaporation of excess irrigation water. Makes land unsuitable for growing crops.
3d. Green Revolutions: Dramatic increase in yield of crops in LDSs due to introduction of new varieites of crops. Still require high levels of fertilizer, water, and pesticides, so they cause the same problem as modern farming methods.
4d. Genetic Engineering: Can produce transgenic plants resistant to insects and herbicides. Soil erosion is minimized.
5d. Domestic Livestock: 2/3 of cropland is devoted to producing livestock feed. Therefore, raising livestock accouts for much of the pollution associated with farming.
- Problems: waste, water use for washing livestock, etc. (Mader 516-519)
E. Energy:
1e. Nonrenewable Sources: Nuclear power (approx. 6% of world's energy supply) and fossil fuels (approx. 75%).
- Nuclear power: Not used very much because of nuclear power dangers and radioactive wastes.
- Fossil Fuels: Oil, natural gas, and coal. Derived from compressed remains of ploants and animal that died many thousands of years ago. U.S. is only 5% of world's population, yet it uses more than half of the fossil fuel energy supply! Pollutants are released into the air as it burns.
2e. Fossil Fuels and Global Climate Change:
- Burning of fossil fuels and burning of forests has caused increase in carbon dioxide in the atmosphere.
- Human activities cause emission of other gases, too, such as methane. These are greenhouse gases, because they allow solar radiation to pass through but hinder the escape of infrared heat back into space.
- Global Warming: Earth may warm to temps never before experienced by living things. If this happens, glaciers will melt, sea levels will rise, and coastal cities could be threatened. Would endanger coral reefs, present assmeblage of species in ecosystems will be disrupted as species migrate north for cooler weather. Loss of species unable to migrate.
(Insert Global Warming picture / global.mitsubishielectric.com / http://global.mitsubishielectric.com/bu/solar/environment/main.html)
3e. Renewable Energy Sources: Hydropower, geothermal, wind, and solar.
- Hydropower: Converts energy of falling water into electricity. Approx. 10% of electric power generated in US, and almost 98% of total renewable energy used.
- Geothermal Energy: Uranium, thorium, radium, and plutonium undergo radioactive decay below Earth's surface and heat the surrounding rocks. When they are in contact w/ water, it heats water. Can be piped up to surface for use.
- Wind Power: Space needed for wind farms that produce electricity is comparable to amount of land required by a coal-fired power plant or solar energy system. Expected to increase use in future.
(Insert Wind Farm picture / www.ronsaari.com / http://www.ronsaari.com/stockImages/windmills/WindFarmPalmSpringsCA.php)
- Energy and the Solar-Hydrogen Revolution: Solar energy must be collected, converted, and stored. Can be used for passive-solar heating of houses, and heat can be sotred in water tanks, rocks, bricks, etc.
- Photovoltaic (solar) cell: A wafer of electron-emitting metal is in contact with another metal that collects the eletrons and passes them along into wires in a steady stream. These cells can be placed on roofs to generate electricity. Can be used to create hydrogen fuel, to be used in future cars. (Mader 520-522)
F. Minerals: Nonrenewable raw materials in Earth's crust that can be extracted. Includes fossil fuels, nonmetallic raw materials, such as sand, gravel, and phophate; and metals, such as aluminum copper, iron, lead, and gold.
- Heavy metals are dangerous to humans: lead, mercury, arsenic, cadmium, tin, chromium, zinc, and copper. Used in electronics, medicines, paints, etc. Inhibit vital enzymes in body.
- Strip / surface mining: One of greatest threats to maintenance of ecosystem and biodiversity. Rain washes toxic waste deposits into streams and rivers.
1f. Hazardous Wastes: Nine most common: heavy metals, synthetic organic compounds, benzene, polychlorinated biphenyls, and chloroform.
- Chlorofluorocarbons: Type of halogenated hydrocarbon in which both chlorine and flourine atoms replace some of the hydrogen atoms. Thin ozone shield, which is essentail for protection of utraviolet radiation.
- Biological Magnification: Wastes that enter and accumulate in the fat or organisms, ans since they are not excreted, they become more and more concentrated as they pass along a food chain. (Mader 522-523)
III. Biodiversity
A. Biodiversity is the variety of life on Earth, described in terms of the number of different species.
- We are in biodiversity crisis: Number of extinctions expected to occur in the near future is unparallel in the history of the Earth.
B. Loss of Biodiversity is due to all of the following:
- Habitat Loss: Human occupation and expansion.
- Alien Species (Exotics): Nonnative members of an ecosystem. Humans introduce them to ecosystems due to colonization, horticulture, and agriculture, and accidental transport. Some are invasive, and crowd out native species.
- Pollution: Acid deposition (weakens trees), global warming (loss of habitat, etc.), ozone depletion (CFCs), and synthetic organic chemicals.
- Overexploitation: Too many individuals are taken from a wild population so it is reduced in number. ie. exotic pets. (Poaching, overfishing, etc.)
- Disease: Exposure to domestic animals and their pathogens occur when humans encroach on wildlife habitats.
(Insert Biodiversity Loss picture / www.greenfacts.org http://www.greenfacts.org/en/desertification/l-3/7-climate-change-biodiversity-loss.htm)
C. Direct Value of Biodiversity: Direct value of wildlife is related to their medicianl value, agricultural value,and consumptive use value.
1c. Medicinal Value: Potent medicines are dervied from plants, fungus, some animals (ie horseshoe crab) and certain types of bacteria.
2c. Agricultural Value: Crops are dervied from wild plants that have been modified to be high producers. Biological pest control, bees pollinating plants, etc/
3c. Consumptive Use Value: Catching of fishes, crustatceans, and mammals. Products sold in marketplaces. Trees for wood, etc.
D. Indirect Value of Biodiversity: Services that are pervasive and not easily discernable.
- Waste Disposal: Decomposers break down dead organic matter and other types of wastes to inorganic nutrients that are used by the producers within ecosystems. If not for this service, Earth would be covered in waste. Some biological communities can break down and immobilize pollutants.
- Provision of freshwater: Water cycle supplies freshwater to terrestrial ecosystems. Provide us w/ fish and other food. "Sponge Effect": Forests soak up water and release it at a regular rate.
- Prevention of Soil Erosion: Intact ecosystems naturally retain soil and prevent soil erosion.
- Biogeochemical Cycles: Biodiversity within ecosystems contributes to the workings of the water, phophorus, nitrogen, carbon, and other biogeochemical cycles, which we depend on for freshwater.
- Regulation of Climate: Trees provide shade and reduce the need for fans and air conditioners. Forests ameliorate the climate because they take up carbon dioxide. Carbon dioxide has a significant impact on global warming, which is increased with deforestation.
- Ecotourism: Relaxing in the wild! :) (Mader 524-530)
IV. Working Toward a Sustainable Society
A. Sustainable Society: One that could always provide the same amount of goods and services for future generations as it does at present. Biodiversity would also be preserved.
1a. Today's Unsustainable Society: Population growth and excessive resource consumption stresses the environment, including worldwide pollution and the extnction of wildlife.
(Insert Species Extinction by State picture / www.unl.edu / http://www.unl.edu/nac/conservation/atlas/Map_Html/Biodiversity/National/Species_Extinctions/Species_extinctions.htm)
2a. Characteristics of a Sustainable Society:
- Makes use of only renewable solar energy.
- Materials cycle through the various populations back to the producer.
- Protection of natural ecosystmes.
- Efficiency (cars, etc.)
3a. Rural Sustainability:
- Emphasis on preservation: ecosystems, agricultural land, groves of fruit trees, etc. Possible steps: plant cover crops, multiuse farming, replenish soil nutrients, low flow or trickle irrigation, increase planting of cultivars, use precision farming, use integrated pest management, etc.
4a. Urban Sustainability:
- Sharing of resources. Possible steps: Energy-efficient transportation system, solar or geothermal energy, utilize green roofs, improve storm-water management, plant native species grasses, create greenbelts, etc.
B. Assessing Economic Well-Being and Quality of Life:
- Gross National Product: Measurement of the flow of money from consumers to businesses, in the form of goods and services purchased. (Total costs of manufacturing, production and srvices in the form of salaries, wages, mortgage and rent, interets and loans, taxes, and profit. Use value, option value, existence value, aesthetic value, cultural value, and scientific and educational value are all factors. (Mader 530-533)
Ok... So I'm not going to lie... I had a REALLY hard time fitting the last part of your powerpoint into chapter 24. I felt like I was reading the wrong chapter, or something. So, I'm including it here in the end:
In a community, relationships among species can be beneficial, damaging or neutral:
Symbiotic: mutually beneficial, both species benefit
Parasitic: one species benefits (“parasite”) and the other is harmed (“host”)
Commensal: One species benefits, the other is unharmed
Mutualism: both species benefit, like symbiosis, but it may appear one species has the advantage, but evolutionarily, over the long-term, both benefit
Predation: Usually considered parasitic, where the predator is the parasite, but can also be seen as mutualistic.
(Frolich PowerPoint Slide 26)
A. Relationships Among Species
- We do still have ecological relationships with “wild” species. Examples:
- Hunt mushrooms
- Create game reserves
- Create national parks
- Household and urban/rural “pests” (e.g. molds, sewer rats)
- Symbiotic micro-organisms (skin and mouth bacteria)
- Disease-causing micro-organisms
(Frolich PowerPoint Slide 26)
B. Our Relationships w/ Domesticated Species
- But mostly we have tight relationships with domesticated species. Basis for ecological relationship:
- Food and agriculture (by far most common—food crops and animals)
- Transportation (“beasts of burden”)
- Care and protection (pets)
- Laboratory study and production
(Frolich PowerPoint Slide 29)
Friday, July 18, 2008
Compendium Review Chapter 23- Pictures
Phosphorous Cycle
Nitrogen Cycle
Greenhouse Effect
The Water Cycle
Grazing and Detrital Food Webs
Terrestrial Biomes
Compendium Review Chapter 23
I. The Nature of Ecosystems
II. Energy Flow
III. Global Biogeochemcial Cycles
I. The Nature of Ecosystems
A. Biosphere: Where organisms are found on planet Earth, from the atmosphere above to the depths of the oceans below, and everything in between.
B. Entire Biosphere is one giant Ecosystem: A place where organisms interact among themselves and with the physical and chemical environment.
- These interactions help maintain both the ecosystem and the biosphere.
- Human interactions can alter interactions between organisms and their environments in ways that reduce the abundance and diversity of life within the ecosystem.
C. Ecosystems: Many different types of terrestial ecosystems, also called biomes.
- Biomes: Temperature and rainfall define the biomes, whose organisms are adapted to the regional climate.
- Examples: Tropical rain forest, savanna, temperate grasslands, temperate forests, deserts, taiga, and tundra.
(Insert Terrestrial Biomes picture / ecology.botany.ufl.edu / http://ecology.botany.ufl.edu/ecologyf02/biodiv.html )
- Aquatic ecosystems: Divided by whether they are freshwater or salt water.
D. Biotic Components of an Ecosystem:
1d. Abiotic components: nonliving.
2d. Biotic components: living things categorized according to the food source.
- Autotrophs: Require only inorganic nutrients and an outside energy source to produce organic nutrients for their own use and for the other members of a community. They are called producers. (ie algae, photosynthetic organisms.)
- Heterotrophs: Need a source of organic nutrients. They are consumers.
* Herbivores: Animals that eat plants or algae. (ie insects, protists.)
* Carnivores: Feed on other animals. (ie birds that feed on insects, hawks feed on birds, etc.)
* Omnivores: Feed on both. (ie humans.)
* Detritus Feeders: Organisms that feed on detritus, which is decomposing particles of organic matter. (ie Earthworms, beetles, etc.)
E. Niche: Role of an organism in an ecosystem: how it eats its food and what eats it, and how it interacts with other populations in the same community.
F. Chemical Flow and Chemical Cycling
1f. Every ecosystem is characterized by two phenomena: energy flow and chemical cycling.
- Energy flow: Begins when producers absorb solar energy.
- Chemical Cycling: Begins when producers take in inorganic nutrients from the physical environment.
- Next, through photosynthesis, producers make organic nutrients directly for themselves and indirectly for the other populations of the ecosystem.
* Energy Flow: As nutrients pass from one population to another, all energy content is converted to heat, which dissipates in the environment.
- Most ecosystems require a constant supply of solar energy.
* Chemicals cycle when inorganic nutrients are returned to the producers from the atmosphere or soil. (Mader 493-495)
II. Energy Flow
A. Various interconnecting paths of energy flow are represented by a food web, which is a diagram that describes trophic (feeding) relationships.
- Two examples: Grazing Web- Begins with an oak tree and grass. Detrital Web- Begins with detritus and the decomposers found within detritus.
(Insert Grazing and Detritus Food Webs picture / project.bio.iastate.edu / http://project.bio.iastate.edu/Courses/biol123/lectures/Lecture06-Ecosystems/slide10.htm)
B. Trophic Levels:
1b. Food Chains: Diagrams that show a single path of energy flow. Ex. In grazing food chain, you would have leaves, followed by caterpillars, followed by birds, followed by hawks. In detrital food chain, you would have detritus, followed by earthworms, followed by shrews.
2b. Trophic level: Composed of all the organisms that feed at a particular link in a food chain. Example: In grazing food web, trees are producers (first trophic level), first series of animals are primary consumers (second trophic level), and the next group of animals are secondary consumers (third trophic level).
C. Ecological Pyramids: The flow of energy with large losses between successive trophic levels.
- Only about 10% of the energy of one trophic level is available to the next tropic level.
1c. Biomass: The number of organisms multiplied by the weight of organic matter within one organism. (Mader 497-498)
III. Global Biogeochemical Cycles
A. All organisms require a variety of organic and / or inorganic nutrients.
1a. Biogeochemical Cycles: Pathways by which chemicals circulate through ecosystems involve both living (biotic) and nonliving (geological) components.
- Gaseous: Element returns to and is withdrawn from the atmosphere as a gas. (ie carbon and nitrogen cycles.)
- Sedimentary: The chemical is absorbed from the soil by plant roots, passed to heterotrophs, and returned to soil by decomposers. (ie phosphorus cycle.)
2a. Chemical Cycling involves a reservoir, an exchange pool, and a biotic community.
- Human activities remove chemicals from reservoirs and exchange pools, and make them available to the biotic community. Can result in pollution, because it upsets the normal balance of nutrients for producers in the environment.
B. The Water Cycle:
1b. Evaporation, precipitation, runoff, etc. See picture. All water is eventually returned to the sea. Aquifer: Rock layers that contain water and release it.
(Insert Water Cycle picture / Frolich PowerPoint Slide 18)
2b. Human Activities:
-Humans interfere w/ water cycle in three ways: First, they take water from aquifers. Second, They clear vegetation from land and build roads and buildings that prevent percolation and increase runoff. Third, they interfere with the natural processes that purify water and instead add pollutants like sewage and chemicals to water.
C. The Carbon Cycle:
1c. Carbon dioxide in atmosphere is the exchange pool for the carbon cycle.
- In this cycle, organisms in both terrestrial and aquatic ecosystems exchange carbon dioxide with the atmosphere. ie. Plants take co2 from air, and through photosynthesis, incorporate carbon into nutrients that are used by autotrophs and heterotrophs. When organisms respire, carbon is returned to the atmosphere as co2. In aquatic, it is indirect: co2 from air combines with h2o to produce bicarbonate ion, a source of carbon for algae that makes food for themselves and for heterotrophs. When aquatic organisms respire, the co2 they give off becomes bicarbonate ion.
2c. Living and dead organisms contain organic carbon and serve as one of the reservoirs for the carbon cycle. Decomposition returns co2 to the atmosphere.
3c. Fossil Fuels: When plant and animal remains are transformed into coal, oil, and natural gas.
4c. Human Activities:
- More co2 is being deposited in the atmosphere than is being removed. Largely due to burning of fossil fuels and destruction of forest. When a forest is destroyed, we reduce a reservoir and the very organisms that take up excess co2.
5c. Global Warming: Human activities emit co2 and other gases, like nitrous oxide into the atmosphere. These gases are known as greenhouse gases, because they allow solar radiation to pass through but hinder the escape of infrared rays back into space.
- Contribute to rise in Earth's ambient temperature, = global warming.
- Higher temperature = greater evaporation of h2o, forming more clouds, and setting up a positive feedback effect that will increase global warming even more.
- Other effects: Temps in polar regions rise, glaciers will melt, sea levels will rise, h2o evap. will increase, = increased rainfall along coasts and dryer conditions inland. Droughts reduce agricultural yields, trees will die, etc. Coastal cities could sink! (Mader 498-499)
(Insert Greenhouse Effect picture / Frolich PowerPoint Slide 21)
D. The Nitrogen Cycle: Nitrogen gas accounts for approx. 78% of the atmosphere.
1d. Ammonium Formation and Use:
- Nitrogen fixation occurs when nitrogen gas is converted to ammonium, a form plants can use.
2d. Nitrate Formation and Use:
- Plants can use nitrates as a source of nitrogen.
- Nitrification: Production of nitrates during the nitrogen cycle. Can occur when cosmic radiation, meteor trails, and lightning provide high energy needed for nitrogen to react with oxygen. Or, when ammonium in the soil is converted to nitrate by soil bacteria, or when nitrate-producing bacteria converts nitrite to nitrate.
- Assimilation: Plants take up ammonia and nitrate from the sol and use these ions to produce proteins and nucleic acids.
(Insert Nitrogen Cycle picture / www.stormfront.org / http://www.stormfront.org/forum/showthread.php?t=325972)
3d. Formation of Nitrogen Gas from Nitrate:
- Denitrification: The conversion of nitrate back to nitrogen gas, which enters the atmosphere. Counterbalances nitrogen fixatin except for human activities.
4d. Human Activities: Significantly alter the transfer rates in the nitrogen cycle by producing fertilizers from nitrogen- nearly doubles the fixation rate. Runs off into water, creates overgrowth of algae, causes over-enrichment, and when algae die off, increased decomposer populations use up all oxygen in water, and results in massive fish kill.
1e. Acid Deposition: Nitrogen oxides and sulfur dioxide enter atmosphere from burning of fossil fuels. These gases combine with water vapor to form acids that return to the earth, and their deposit affects forest and lakes.
- Creation of smog, and trapped pollutants.
E. The Phosphorus Cycle: Phosphorous trapped in oceanic sediments moves onto land after a geological upheaval. Weathering of rocks places phosphate ions into soil. Some of this phosphate is used by plants in a variety of molecules, and the nucleotides that become a part of DNA and RNA. Animals eat producers and incorporate some of the phosphate into teeth, bones, and shells, which take many years to decompose.
(Insert Phosphorous Cycle picture / www.biologycorner.com / http://www.biologycorner.com/bio4/notes/chap45.html )
1e. Phosphorus and Water Pollution:
- Cultural Eutrophication: Overenrichment of waterways due to humans use of phosphate for fertilizer, animal wastes from livestock feedlots, and discharge from sewage treatment plants.
- Biological Magnification: Occurs as materials pass along a food chain and become more and more concentrated because they remain in body and are not excreted.
- Pollutants: Waste dumping, offshore mining and shipping, oil spills, etc.
- Many species are at the brink of extinction. (Mader 500-505)
II. Energy Flow
III. Global Biogeochemcial Cycles
I. The Nature of Ecosystems
A. Biosphere: Where organisms are found on planet Earth, from the atmosphere above to the depths of the oceans below, and everything in between.
B. Entire Biosphere is one giant Ecosystem: A place where organisms interact among themselves and with the physical and chemical environment.
- These interactions help maintain both the ecosystem and the biosphere.
- Human interactions can alter interactions between organisms and their environments in ways that reduce the abundance and diversity of life within the ecosystem.
C. Ecosystems: Many different types of terrestial ecosystems, also called biomes.
- Biomes: Temperature and rainfall define the biomes, whose organisms are adapted to the regional climate.
- Examples: Tropical rain forest, savanna, temperate grasslands, temperate forests, deserts, taiga, and tundra.
(Insert Terrestrial Biomes picture / ecology.botany.ufl.edu / http://ecology.botany.ufl.edu/ecologyf02/biodiv.html )
- Aquatic ecosystems: Divided by whether they are freshwater or salt water.
D. Biotic Components of an Ecosystem:
1d. Abiotic components: nonliving.
2d. Biotic components: living things categorized according to the food source.
- Autotrophs: Require only inorganic nutrients and an outside energy source to produce organic nutrients for their own use and for the other members of a community. They are called producers. (ie algae, photosynthetic organisms.)
- Heterotrophs: Need a source of organic nutrients. They are consumers.
* Herbivores: Animals that eat plants or algae. (ie insects, protists.)
* Carnivores: Feed on other animals. (ie birds that feed on insects, hawks feed on birds, etc.)
* Omnivores: Feed on both. (ie humans.)
* Detritus Feeders: Organisms that feed on detritus, which is decomposing particles of organic matter. (ie Earthworms, beetles, etc.)
E. Niche: Role of an organism in an ecosystem: how it eats its food and what eats it, and how it interacts with other populations in the same community.
F. Chemical Flow and Chemical Cycling
1f. Every ecosystem is characterized by two phenomena: energy flow and chemical cycling.
- Energy flow: Begins when producers absorb solar energy.
- Chemical Cycling: Begins when producers take in inorganic nutrients from the physical environment.
- Next, through photosynthesis, producers make organic nutrients directly for themselves and indirectly for the other populations of the ecosystem.
* Energy Flow: As nutrients pass from one population to another, all energy content is converted to heat, which dissipates in the environment.
- Most ecosystems require a constant supply of solar energy.
* Chemicals cycle when inorganic nutrients are returned to the producers from the atmosphere or soil. (Mader 493-495)
II. Energy Flow
A. Various interconnecting paths of energy flow are represented by a food web, which is a diagram that describes trophic (feeding) relationships.
- Two examples: Grazing Web- Begins with an oak tree and grass. Detrital Web- Begins with detritus and the decomposers found within detritus.
(Insert Grazing and Detritus Food Webs picture / project.bio.iastate.edu / http://project.bio.iastate.edu/Courses/biol123/lectures/Lecture06-Ecosystems/slide10.htm)
B. Trophic Levels:
1b. Food Chains: Diagrams that show a single path of energy flow. Ex. In grazing food chain, you would have leaves, followed by caterpillars, followed by birds, followed by hawks. In detrital food chain, you would have detritus, followed by earthworms, followed by shrews.
2b. Trophic level: Composed of all the organisms that feed at a particular link in a food chain. Example: In grazing food web, trees are producers (first trophic level), first series of animals are primary consumers (second trophic level), and the next group of animals are secondary consumers (third trophic level).
C. Ecological Pyramids: The flow of energy with large losses between successive trophic levels.
- Only about 10% of the energy of one trophic level is available to the next tropic level.
1c. Biomass: The number of organisms multiplied by the weight of organic matter within one organism. (Mader 497-498)
III. Global Biogeochemical Cycles
A. All organisms require a variety of organic and / or inorganic nutrients.
1a. Biogeochemical Cycles: Pathways by which chemicals circulate through ecosystems involve both living (biotic) and nonliving (geological) components.
- Gaseous: Element returns to and is withdrawn from the atmosphere as a gas. (ie carbon and nitrogen cycles.)
- Sedimentary: The chemical is absorbed from the soil by plant roots, passed to heterotrophs, and returned to soil by decomposers. (ie phosphorus cycle.)
2a. Chemical Cycling involves a reservoir, an exchange pool, and a biotic community.
- Human activities remove chemicals from reservoirs and exchange pools, and make them available to the biotic community. Can result in pollution, because it upsets the normal balance of nutrients for producers in the environment.
B. The Water Cycle:
1b. Evaporation, precipitation, runoff, etc. See picture. All water is eventually returned to the sea. Aquifer: Rock layers that contain water and release it.
(Insert Water Cycle picture / Frolich PowerPoint Slide 18)
2b. Human Activities:
-Humans interfere w/ water cycle in three ways: First, they take water from aquifers. Second, They clear vegetation from land and build roads and buildings that prevent percolation and increase runoff. Third, they interfere with the natural processes that purify water and instead add pollutants like sewage and chemicals to water.
C. The Carbon Cycle:
1c. Carbon dioxide in atmosphere is the exchange pool for the carbon cycle.
- In this cycle, organisms in both terrestrial and aquatic ecosystems exchange carbon dioxide with the atmosphere. ie. Plants take co2 from air, and through photosynthesis, incorporate carbon into nutrients that are used by autotrophs and heterotrophs. When organisms respire, carbon is returned to the atmosphere as co2. In aquatic, it is indirect: co2 from air combines with h2o to produce bicarbonate ion, a source of carbon for algae that makes food for themselves and for heterotrophs. When aquatic organisms respire, the co2 they give off becomes bicarbonate ion.
2c. Living and dead organisms contain organic carbon and serve as one of the reservoirs for the carbon cycle. Decomposition returns co2 to the atmosphere.
3c. Fossil Fuels: When plant and animal remains are transformed into coal, oil, and natural gas.
4c. Human Activities:
- More co2 is being deposited in the atmosphere than is being removed. Largely due to burning of fossil fuels and destruction of forest. When a forest is destroyed, we reduce a reservoir and the very organisms that take up excess co2.
5c. Global Warming: Human activities emit co2 and other gases, like nitrous oxide into the atmosphere. These gases are known as greenhouse gases, because they allow solar radiation to pass through but hinder the escape of infrared rays back into space.
- Contribute to rise in Earth's ambient temperature, = global warming.
- Higher temperature = greater evaporation of h2o, forming more clouds, and setting up a positive feedback effect that will increase global warming even more.
- Other effects: Temps in polar regions rise, glaciers will melt, sea levels will rise, h2o evap. will increase, = increased rainfall along coasts and dryer conditions inland. Droughts reduce agricultural yields, trees will die, etc. Coastal cities could sink! (Mader 498-499)
(Insert Greenhouse Effect picture / Frolich PowerPoint Slide 21)
D. The Nitrogen Cycle: Nitrogen gas accounts for approx. 78% of the atmosphere.
1d. Ammonium Formation and Use:
- Nitrogen fixation occurs when nitrogen gas is converted to ammonium, a form plants can use.
2d. Nitrate Formation and Use:
- Plants can use nitrates as a source of nitrogen.
- Nitrification: Production of nitrates during the nitrogen cycle. Can occur when cosmic radiation, meteor trails, and lightning provide high energy needed for nitrogen to react with oxygen. Or, when ammonium in the soil is converted to nitrate by soil bacteria, or when nitrate-producing bacteria converts nitrite to nitrate.
- Assimilation: Plants take up ammonia and nitrate from the sol and use these ions to produce proteins and nucleic acids.
(Insert Nitrogen Cycle picture / www.stormfront.org / http://www.stormfront.org/forum/showthread.php?t=325972)
3d. Formation of Nitrogen Gas from Nitrate:
- Denitrification: The conversion of nitrate back to nitrogen gas, which enters the atmosphere. Counterbalances nitrogen fixatin except for human activities.
4d. Human Activities: Significantly alter the transfer rates in the nitrogen cycle by producing fertilizers from nitrogen- nearly doubles the fixation rate. Runs off into water, creates overgrowth of algae, causes over-enrichment, and when algae die off, increased decomposer populations use up all oxygen in water, and results in massive fish kill.
1e. Acid Deposition: Nitrogen oxides and sulfur dioxide enter atmosphere from burning of fossil fuels. These gases combine with water vapor to form acids that return to the earth, and their deposit affects forest and lakes.
- Creation of smog, and trapped pollutants.
E. The Phosphorus Cycle: Phosphorous trapped in oceanic sediments moves onto land after a geological upheaval. Weathering of rocks places phosphate ions into soil. Some of this phosphate is used by plants in a variety of molecules, and the nucleotides that become a part of DNA and RNA. Animals eat producers and incorporate some of the phosphate into teeth, bones, and shells, which take many years to decompose.
(Insert Phosphorous Cycle picture / www.biologycorner.com / http://www.biologycorner.com/bio4/notes/chap45.html )
1e. Phosphorus and Water Pollution:
- Cultural Eutrophication: Overenrichment of waterways due to humans use of phosphate for fertilizer, animal wastes from livestock feedlots, and discharge from sewage treatment plants.
- Biological Magnification: Occurs as materials pass along a food chain and become more and more concentrated because they remain in body and are not excreted.
- Pollutants: Waste dumping, offshore mining and shipping, oil spills, etc.
- Many species are at the brink of extinction. (Mader 500-505)
Compendium Review Chapter 22- Pictures
Cro-Magnon Skull
Neanderthal and Modern Human Skull Comparison
Homo erectus
Homo habilis
Evolution of Primates
Human / Chimpanzee Skeletons 2
Human / Chimpanzee Skeletons 1
Evidence for Historical Fact of Evolution
Ambulocetus: Believes to have given rise to whales.
Charles Darwin
Early Earth
Stanley Miller Experiment
Stanley Miller
History of Life on Earth Chart
Compendium Review Chapter 22
I. Origin of Life
II. Biological Evolution
III. Classification of Humans
IV. Evolution of Hominids
V. Evolution of Humans
I. Origin of Life
A. Fundamental Principle of Biology: All living things are made of cells and every cell comes from a preexisting cell.
1a. Chemical Evolution: A slow increase in the complexity of chemicals. (Mader 468)
B. To understand evolution, we must appreciate deep time- time stretching beyond what is easy to intuitively grasp.
1b. Toilet paper analogy—if a roll of toilet paper is Earth history, humans reside in the shreds at the end of the very last sheet. (Frolich PowerPoint Slide 4)
(Insert Key Events of History of Life picture / Frolich PowerPoint Slide 5)
C. The Primitive Earth:
1c. Sun and Planets: Probably formed from aggregates of dust particles and debris,taking approx. 10-billion years.
- 4.6 billion years ago: solar system in place.
2c. First atmosphere was probably formed by gases escaping from volcanoes. Therefore, the primitive atmosphere would have been made up of mostly water vapor, nitrogen, and carbon dioxide, along with small amounts of hydrogen and carbon monoxide. (Free oxygen was scarce, if any.)
- Earth was extremely hot, and as it cooled, it formed dense clouds.
- Water vapor condensed to liquid water, and rain began to fall. = Oceans. (Mader 468)
- How do we know? Existing ancient rocks. (Frolich PowerPoint Slide 6)
D. Small Organic Molecules:
1d. Rain washed gases into oceans.
- The great deal of energy present (ie volcanoes, lightning, ultraviolet radiation, etc.) made the primitive gases react with one another and produce small organic compounds, such as nucleotides and amino acids.
- Experiment conducted by Stanley Miller confirms this theory. (Mader 468-469)
(Insert Stanley Miller picture / fig.cox.miami.edu / http://fig.cox.miami.edu/~cmallery/150/life)
(Insert Stanly Miller Experiment picture / Frolich PowerPoint Slide 7)
E. Macromolecules: Newly formed small organic molecules probably joined to produce organic macromolecules.
1e. RNA- first hypothesis: The only macromolecule needed to progress toward formation of the first cell was RNA (ribonucleic acid). It is possible that, then, RNA could have carried out the processes of life commonly associated today with DNA.
2e. Protein-first hypothesis: Amino acids join together when exposed to dry heat. This theory suggests that amino acids collected in shallow puddles, and the heat of the sun caused to to form proteinoids (small polypeptides) that have some catalytic properties. When returned to water, they form microspheres, sturctues that are made of only protein but have mnay of the properties of a cell.
F. The Protocell: Can carry on metablism but not reproduce.
- Could have come about by a lipd that was made available to microspheres, the two tend to associate, and produce a pipid-protein membrane.
- Protocell could have used the abundant small organic molecules in the ocean as food.
- Protocell was most likely a heterotroph: organism that takes in preformed food.
- Also would have been a fementer, since there was no free oxygen. (Mader 469)
(Insert Early Earth picture / Frolich PowerPoint Slide 6)
G. The True Cell: How did the first cell acquire both DNA and enzymatic proteins?
1g. RNA-first Hypothesis: First cell had RNA genes that, similar to mRNA, could have specified protein synthesis. Some of these proteins would have been enzymes. One of these enzymes may have used RNA as a template to form DNA, and replication would have then proceeded normally.
2g. Protein-first Hypothesis: Some of the proteins in the protocell would have evolved the enzymatic ability to synthesize DNA from nucleotides in the ocean. DNA would have then gone on to specify protein synthesis, and the cell could have acquired all its enzymes, inlcuding those that replicate DNA. (Mader 468-469)
II. Biological Evolution
A. Since the first true cells were the simplest of life cells, they must have been prokaryotic cells, lacking a nucleus.
- Eukaryotic cells, which have nuclei, evolved from these first cells.
- Multi-cellular organisms and other kingdoms evolved, like fungi and plants.
B. Biological Evolution: The process by which a species changes throughout time. Two important aspects:
- Descent from a common ancestor, which explains what all living things have a commno chemistry and cellular structure.
- Adaptation to the environment, which enables an organism to survive and reproduce in its environment. (Explains diversity of life.)
C. Common Descent: Life forms change over time and from place to place.
1c. Charles Darwin: English naturlaist who first formulated the teory of evolution based on his travels at the age of 22.
- Gathered evidence to support the idea of common descent, based in fossil, anatomical, and biogeographical data. (Mader 470)
(Insert Charles Darwin picture /www.paracompusa.com / http://www.paracompusa.com/SmartScience/Popa/Vol4-2.html)
D. Evidence for Historical Fact of Evolution
1d. Fossil record
–Most rocks contain fossils (in sedimentary rock). (Frolich PowerPoint Slide 8) Best evidence because they are the actual remains of species that lived on Earth at least 10000 years ago and up to billions of years ago. Includes trails, footprints, burrows, casts, preserved droppings, bone, impressions, and insects trapped in tree resin.
- Paleontologists: Find and remove fossils from strata.
- Fossil Record: History of life recorded by fossils.
(Mader 470)
–Long-term change in biological communities. (Frolich PowerPoint Slide 8)
- In general, life progressed from the simple to the complex: Unicellular prokaryotes, unicellular eukaryotes, multicellular eukaryotes, fishes, terrestial plants, animals. On land, nonflowering plants, flowering plants, amphibians, reptiles (including dinosaurs), birds, etc. (Mader 471)
(Insert picture of Ambulocetus / http://www.flickr.com/ / http://www.flickr.com/photos/68509222@N00/384835318/)
2d. Transitional Fossils: Those that have characteristics of two different groups: origin of mammals, origin of birds.
- Anatomical similarities.
- Shared embryological features.
- Shared biochemical and genetic features.
(Insert Evidence for Historical Fact of Evolution picture / Frolich PowerPoint Slide 8)
(Frolich PowerPoint Slide 8)
E. Different Types of Evidence Support the Hypothesis that Organisms are Related Through Common Descent.
1e. Biogeographical Evidence: Biogeography: The study of the distribution of plants and animals in different places throughout the world.
- Life forms evolved in a particular locale and then spread out, which provides for a variety of plants and animals where geography separates continents, islands, or seas.
- Ex. Rabbits were not found in S. America, though the geography was suited for them, because they evolved somewhere else and could not reach S. America.
2e. Anatomical Evidence: Common Descent allows for the explanation for anatomical similarities among organisms.
- Ex. Forelimbs are used by birds, whales, horses, lizards, and monkeys, for different purposes.
- These are Homologous Structures: similar in structure anatomically because they are inherited from a common ancestor.
- Analogous Structures: Serve the same function, but are not constructed similarly, nor do they share a common ancestry.
- Ex. Wings of birds and insects, the jointed appendages of a lobster, and humans are analogous structures.
- Vestigal Structures: Anatomical features that are fully developed in one group of organisms, but are reduced and may have no function in similar groups.
- Ex. Ancestors of whales walked on land. "Modern" whales have a vestigial pelvic girdle and legs, but are completely aquatic. These are also explained by Common Descent. Traces of evolutionary history.
3e. Biochemical Evidence: Almost all living organisms use the same basic biochemical molecules, including DNA, ATP, etc.
- Therefore, humans share a large number of genes with much simpler organisms. Life's vast diversity has come about by only a slight difference in the regulation of genes.
F. Intelligent Design:
- Evolutionary theory has been supported by repeated scientific experiments and observations.
- Intelligent Design argues that the diversity of life could never have arisen without the involvement of an "intelligent agent". Faith-based, not science-based.
G. Natural Selection: Mechanism for adaptation.
- Adaptation: A species becomes suited to its environment.
- Critical Elements of Natural Selection are as follows:
* Variation: Individual members of a species vary in physical characteristics. Physical variations can be passed from generation to generation.
* Competition for Limited Resources: The number in each generation usually stays about the same: resources are limited and competition for resources reults in unequal reporduction among members of a population.
* Adaptation: Members of a population with advantageous traits capture more resources and are more likely to reproduce and pass on those traits. Over time, the environment "selects" for the better-adapted traits. Therefore, each subsequent generation includes more individuals that are adapted in the same way to the environment.
- Accounts for great diversity of life. (Mader 474)
III. Classification of Humans
A. Biologists classify organisms according to their evolutionary relatedness.
1a. Binomial Name: Each organism has a name that gives its genus and species.
- Organisms in the same domain have general characteristics in common.
- Those in the same genus have very specific characteristics in common.
B. DNA Data and Human Evolution: DNA data is being relied on more heavily today to trace the history of life.
1b. 1970s: Carl Woese reports that on the basis of rRNA data, there are three domains of life and the archaea are more closely related to eukaryotes than to bacteria. Animals are more closely related to fungi than plants. (Mader 475)
(Insert Three Domain System of Classification picture / kilby.sac.on.ca / http://kilby.sac.on.ca/faculty/dgalajda/oacbiology/domains__cladistics.htm)
C. Humans Are Primates
- Our closest living relatives are monkeys and apes (anthropoids).
- We share a common ancestor, most recently with apes, farther into deep time with monkeys and even farther in with lemurs and tarsurs (prosimians).
- The living species are not our actual ancestors—we need the fossil record to see them.
(Frolich PowerPoint Slide 9)
- Primates have mobile limbs (w/ five digits each, opposable thumb); grasping hands; a flattened face; binocular vision (including cones); a large, complex brain; and a reduced reproductive rate.
- All traits shared with humans.
D. Comparing Human Skeleton to the Chimpanzee Skeleton
1d. The genomes of humans and chimpanzees are 99% identical.
- 1% difference: Humans, not chimps, are adapted for an upright stance. (Mader 476-477)
(Insert Human / Chimpanzee Skeletons pictures / http://www.flickr.com/ / http://www.flickr.com/photos/mindfuldocumentation/71000531/)
(Insert Evolution of Primates picture / Frolich PowerPoint Slide 9)
IV. Evolution of Hominids
A. Evolutionary Tree: A working hypothesis of the past history of a group of organisms. (See Evolution of Primates picture.)
B. The First Hominids: Hominid refers to our branch of the evolutionary tree.
- Lineage: Any two lines of descent.
- Each lineage throughout time accumulates genetic changes, which lead to RNA and protein changes.
- Molecular data suggest that hominids split from the ape line of descent about 7 mya.
C. Hominid Features: Anatomical features are used to determine if a fossil is a hominid.
- Bipedal posture: Walking on two feet.
- Shape of the face: Flatter, more pronounced chin.
- Teeth are generally smaller and less specialized.
- Brain size.
D. Earliest Fossil Hominids
- Odest fossil: Sahelanthropus tchadensis, dated 7 mya, found in Chad, central Africa. Only found a skull.
- Orrorin tugenensis: dated 6 mya, found in eastern Africa. Limb anatomy suggests bipedal posture.
- Ardipithecus kadabba: dated between 5.8-5.2 mya.
E. Evolution of Australopithecines: Beginning of hominid line of descent.
- Group of species that evolved and diversified in Africa.
- Some were slender, some were powerful.
- Fed on soft fruits and leaves, some of the more "robust" fed on a more fibrous diet.
- First was unearthed in Southern Africa. (Australopithecus africanus)
- Walked upright. Proportions of limbs were apelike.
- Relatively large brain.
- A. afarensis: Lucy. Dated at 3.18 mya, she stood upright and walked bipedally.
Ape-like above waist (small brain) and humanlike below the waist (walked erect). Proves human characteristics did not evolve all at one time. = Mosaic evolution.
V. Evolution of Humans
A.Fossils are assigned to the genus Homo if the following criteria are met:
- Brain size is 600 cm3 or greater.
- The jaw and teeth resemble those of humans.
- Tool use is evident.
B. Early Homo: Homo habilis "handy man": Dated between 2.0 and 1.9 mya.
- May be ancestral to early humans due to larger brain size, smaller cheek teeth, possibility of speech, and indication of tool use. May have been the beginnings of society and culture, if they hunted and ate together.
(Insert Homo Habilis picture / primatas.no.sapo.pt / http://primatas.no.sapo.pt/homem.htm)
C. Homo Erectus: Fossils found in Africa, Asia, and Europe. Dated between 1.9 and 0.3 mya.
- First H. erectus to be unearthed was in 1891, by Eugene Dubois.
- Several different species are included in this group, although all are similar in appearance.
- Compared with H. habilis, H. erectus had a larger brain and a flatter face. Nose projected, much taller. Were erect, with striding gait. Skeleton still showed some australopithecine features. Believed to have migrated from Africa into Asia and Europe.
- First hominid to use fire, and fashioned more advanced tools than early Homos.
- Believed to have used "home bases".
- Language and culture.
(Insert Homo Erectus picture / www.forcesitaly.org / http://www.forcesitaly.org/italy/immagini?M=D)
D. Evolution of Modern Humans
1d. Most accept the idea that Homo sapiens (modern humans) evolved from H. erectus. (Mader 482-484)
- Ability to interbreed.
- Little anatomical difference among populations.
- Little biochemical difference among populations.
- DNA and protein analysis show recent single common ancestor within 1 million years, perhaps only 200,000 years ago. (Frolich PowerPoint Slide 11)
2d. Multiregional Continuity Hypothesis: Belief that Homo sapiens evolved in several different locations. (ie. Asia, Africa, and Europe.)
3d. Others argue that it is unlikely that evolution would have produced essentially the same result in these different places. They suggest the following theory:
4d. Out-of-Africa Hypothesis: Proposes that H. sapiens evolved from H. erectus only in Africa, and thereafter migrated to Europe and Asia about 100000 years BP. This hypothesis suggests that we are more genetically similar than the other hypothesis, and this is the more accepted hyposthesis of the two.
E. Neandertals:
- First Neandertal discovered in Neander Valley, Germany, approx. 200000 years BP.
- Massive brow ridges, and their nose, jaws and teeth protruded far forward. Low forehead, lower jaw lacked a chin. Brain was slightly larger than modern humans. Heavily muscled. Lived in Europe and Asia during the lst ice age.
- Culturally advanced. May have built houses when not living in caves. Manufactured a variety of stone tools, including spear points. Hunted bears, woolly mammoths, rhinos, etc. Used and controlled fire. Buried their dead w/ flowers. may have even had a religion. Capable of thinking symbolically. (Mader 485)
(Insert Neanderthal and Modern Human Skulls Comparison picture / Frolich PowerPoint Slide 13)
F. Cro-Magnons: Oldest fossils to be designated Homo sapiens.
- Named after fossil location in France.
- Believed to be the modern humans who entered Asia and Europe from Africa 100000 years BP.
- Thoroughly modern appearance.
- Did not interbreed with Neanderthals, but seemed to coexist.
- Made advanced stone tools, including compound tools.
- May have been first to throw spears, and were accomplished hunters.
- Culture included art.
(Insert Cro-Magnon Skull picture / www.skadi.net / http://www.skadi.net/forum/showthread.php?t=11043)
G. Human Variation
1g. Widely distributed about the globe. Different ethnicities.
- Could be due to environmental adaptations. (ie dark and light skin)
- Bergmann's rule: animals in colder regions have a bulkier body build.
- Allen's rule: Animals in colder regions have shorter limbs, digits, and ears, to help regulate body temperature.
II. Biological Evolution
III. Classification of Humans
IV. Evolution of Hominids
V. Evolution of Humans
I. Origin of Life
A. Fundamental Principle of Biology: All living things are made of cells and every cell comes from a preexisting cell.
1a. Chemical Evolution: A slow increase in the complexity of chemicals. (Mader 468)
B. To understand evolution, we must appreciate deep time- time stretching beyond what is easy to intuitively grasp.
1b. Toilet paper analogy—if a roll of toilet paper is Earth history, humans reside in the shreds at the end of the very last sheet. (Frolich PowerPoint Slide 4)
(Insert Key Events of History of Life picture / Frolich PowerPoint Slide 5)
C. The Primitive Earth:
1c. Sun and Planets: Probably formed from aggregates of dust particles and debris,taking approx. 10-billion years.
- 4.6 billion years ago: solar system in place.
2c. First atmosphere was probably formed by gases escaping from volcanoes. Therefore, the primitive atmosphere would have been made up of mostly water vapor, nitrogen, and carbon dioxide, along with small amounts of hydrogen and carbon monoxide. (Free oxygen was scarce, if any.)
- Earth was extremely hot, and as it cooled, it formed dense clouds.
- Water vapor condensed to liquid water, and rain began to fall. = Oceans. (Mader 468)
- How do we know? Existing ancient rocks. (Frolich PowerPoint Slide 6)
D. Small Organic Molecules:
1d. Rain washed gases into oceans.
- The great deal of energy present (ie volcanoes, lightning, ultraviolet radiation, etc.) made the primitive gases react with one another and produce small organic compounds, such as nucleotides and amino acids.
- Experiment conducted by Stanley Miller confirms this theory. (Mader 468-469)
(Insert Stanley Miller picture / fig.cox.miami.edu / http://fig.cox.miami.edu/~cmallery/150/life)
(Insert Stanly Miller Experiment picture / Frolich PowerPoint Slide 7)
E. Macromolecules: Newly formed small organic molecules probably joined to produce organic macromolecules.
1e. RNA- first hypothesis: The only macromolecule needed to progress toward formation of the first cell was RNA (ribonucleic acid). It is possible that, then, RNA could have carried out the processes of life commonly associated today with DNA.
2e. Protein-first hypothesis: Amino acids join together when exposed to dry heat. This theory suggests that amino acids collected in shallow puddles, and the heat of the sun caused to to form proteinoids (small polypeptides) that have some catalytic properties. When returned to water, they form microspheres, sturctues that are made of only protein but have mnay of the properties of a cell.
F. The Protocell: Can carry on metablism but not reproduce.
- Could have come about by a lipd that was made available to microspheres, the two tend to associate, and produce a pipid-protein membrane.
- Protocell could have used the abundant small organic molecules in the ocean as food.
- Protocell was most likely a heterotroph: organism that takes in preformed food.
- Also would have been a fementer, since there was no free oxygen. (Mader 469)
(Insert Early Earth picture / Frolich PowerPoint Slide 6)
G. The True Cell: How did the first cell acquire both DNA and enzymatic proteins?
1g. RNA-first Hypothesis: First cell had RNA genes that, similar to mRNA, could have specified protein synthesis. Some of these proteins would have been enzymes. One of these enzymes may have used RNA as a template to form DNA, and replication would have then proceeded normally.
2g. Protein-first Hypothesis: Some of the proteins in the protocell would have evolved the enzymatic ability to synthesize DNA from nucleotides in the ocean. DNA would have then gone on to specify protein synthesis, and the cell could have acquired all its enzymes, inlcuding those that replicate DNA. (Mader 468-469)
II. Biological Evolution
A. Since the first true cells were the simplest of life cells, they must have been prokaryotic cells, lacking a nucleus.
- Eukaryotic cells, which have nuclei, evolved from these first cells.
- Multi-cellular organisms and other kingdoms evolved, like fungi and plants.
B. Biological Evolution: The process by which a species changes throughout time. Two important aspects:
- Descent from a common ancestor, which explains what all living things have a commno chemistry and cellular structure.
- Adaptation to the environment, which enables an organism to survive and reproduce in its environment. (Explains diversity of life.)
C. Common Descent: Life forms change over time and from place to place.
1c. Charles Darwin: English naturlaist who first formulated the teory of evolution based on his travels at the age of 22.
- Gathered evidence to support the idea of common descent, based in fossil, anatomical, and biogeographical data. (Mader 470)
(Insert Charles Darwin picture /www.paracompusa.com / http://www.paracompusa.com/SmartScience/Popa/Vol4-2.html)
D. Evidence for Historical Fact of Evolution
1d. Fossil record
–Most rocks contain fossils (in sedimentary rock). (Frolich PowerPoint Slide 8) Best evidence because they are the actual remains of species that lived on Earth at least 10000 years ago and up to billions of years ago. Includes trails, footprints, burrows, casts, preserved droppings, bone, impressions, and insects trapped in tree resin.
- Paleontologists: Find and remove fossils from strata.
- Fossil Record: History of life recorded by fossils.
(Mader 470)
–Long-term change in biological communities. (Frolich PowerPoint Slide 8)
- In general, life progressed from the simple to the complex: Unicellular prokaryotes, unicellular eukaryotes, multicellular eukaryotes, fishes, terrestial plants, animals. On land, nonflowering plants, flowering plants, amphibians, reptiles (including dinosaurs), birds, etc. (Mader 471)
(Insert picture of Ambulocetus / http://www.flickr.com/ / http://www.flickr.com/photos/68509222@N00/384835318/)
2d. Transitional Fossils: Those that have characteristics of two different groups: origin of mammals, origin of birds.
- Anatomical similarities.
- Shared embryological features.
- Shared biochemical and genetic features.
(Insert Evidence for Historical Fact of Evolution picture / Frolich PowerPoint Slide 8)
(Frolich PowerPoint Slide 8)
E. Different Types of Evidence Support the Hypothesis that Organisms are Related Through Common Descent.
1e. Biogeographical Evidence: Biogeography: The study of the distribution of plants and animals in different places throughout the world.
- Life forms evolved in a particular locale and then spread out, which provides for a variety of plants and animals where geography separates continents, islands, or seas.
- Ex. Rabbits were not found in S. America, though the geography was suited for them, because they evolved somewhere else and could not reach S. America.
2e. Anatomical Evidence: Common Descent allows for the explanation for anatomical similarities among organisms.
- Ex. Forelimbs are used by birds, whales, horses, lizards, and monkeys, for different purposes.
- These are Homologous Structures: similar in structure anatomically because they are inherited from a common ancestor.
- Analogous Structures: Serve the same function, but are not constructed similarly, nor do they share a common ancestry.
- Ex. Wings of birds and insects, the jointed appendages of a lobster, and humans are analogous structures.
- Vestigal Structures: Anatomical features that are fully developed in one group of organisms, but are reduced and may have no function in similar groups.
- Ex. Ancestors of whales walked on land. "Modern" whales have a vestigial pelvic girdle and legs, but are completely aquatic. These are also explained by Common Descent. Traces of evolutionary history.
3e. Biochemical Evidence: Almost all living organisms use the same basic biochemical molecules, including DNA, ATP, etc.
- Therefore, humans share a large number of genes with much simpler organisms. Life's vast diversity has come about by only a slight difference in the regulation of genes.
F. Intelligent Design:
- Evolutionary theory has been supported by repeated scientific experiments and observations.
- Intelligent Design argues that the diversity of life could never have arisen without the involvement of an "intelligent agent". Faith-based, not science-based.
G. Natural Selection: Mechanism for adaptation.
- Adaptation: A species becomes suited to its environment.
- Critical Elements of Natural Selection are as follows:
* Variation: Individual members of a species vary in physical characteristics. Physical variations can be passed from generation to generation.
* Competition for Limited Resources: The number in each generation usually stays about the same: resources are limited and competition for resources reults in unequal reporduction among members of a population.
* Adaptation: Members of a population with advantageous traits capture more resources and are more likely to reproduce and pass on those traits. Over time, the environment "selects" for the better-adapted traits. Therefore, each subsequent generation includes more individuals that are adapted in the same way to the environment.
- Accounts for great diversity of life. (Mader 474)
III. Classification of Humans
A. Biologists classify organisms according to their evolutionary relatedness.
1a. Binomial Name: Each organism has a name that gives its genus and species.
- Organisms in the same domain have general characteristics in common.
- Those in the same genus have very specific characteristics in common.
B. DNA Data and Human Evolution: DNA data is being relied on more heavily today to trace the history of life.
1b. 1970s: Carl Woese reports that on the basis of rRNA data, there are three domains of life and the archaea are more closely related to eukaryotes than to bacteria. Animals are more closely related to fungi than plants. (Mader 475)
(Insert Three Domain System of Classification picture / kilby.sac.on.ca / http://kilby.sac.on.ca/faculty/dgalajda/oacbiology/domains__cladistics.htm)
C. Humans Are Primates
- Our closest living relatives are monkeys and apes (anthropoids).
- We share a common ancestor, most recently with apes, farther into deep time with monkeys and even farther in with lemurs and tarsurs (prosimians).
- The living species are not our actual ancestors—we need the fossil record to see them.
(Frolich PowerPoint Slide 9)
- Primates have mobile limbs (w/ five digits each, opposable thumb); grasping hands; a flattened face; binocular vision (including cones); a large, complex brain; and a reduced reproductive rate.
- All traits shared with humans.
D. Comparing Human Skeleton to the Chimpanzee Skeleton
1d. The genomes of humans and chimpanzees are 99% identical.
- 1% difference: Humans, not chimps, are adapted for an upright stance. (Mader 476-477)
(Insert Human / Chimpanzee Skeletons pictures / http://www.flickr.com/ / http://www.flickr.com/photos/mindfuldocumentation/71000531/)
(Insert Evolution of Primates picture / Frolich PowerPoint Slide 9)
IV. Evolution of Hominids
A. Evolutionary Tree: A working hypothesis of the past history of a group of organisms. (See Evolution of Primates picture.)
B. The First Hominids: Hominid refers to our branch of the evolutionary tree.
- Lineage: Any two lines of descent.
- Each lineage throughout time accumulates genetic changes, which lead to RNA and protein changes.
- Molecular data suggest that hominids split from the ape line of descent about 7 mya.
C. Hominid Features: Anatomical features are used to determine if a fossil is a hominid.
- Bipedal posture: Walking on two feet.
- Shape of the face: Flatter, more pronounced chin.
- Teeth are generally smaller and less specialized.
- Brain size.
D. Earliest Fossil Hominids
- Odest fossil: Sahelanthropus tchadensis, dated 7 mya, found in Chad, central Africa. Only found a skull.
- Orrorin tugenensis: dated 6 mya, found in eastern Africa. Limb anatomy suggests bipedal posture.
- Ardipithecus kadabba: dated between 5.8-5.2 mya.
E. Evolution of Australopithecines: Beginning of hominid line of descent.
- Group of species that evolved and diversified in Africa.
- Some were slender, some were powerful.
- Fed on soft fruits and leaves, some of the more "robust" fed on a more fibrous diet.
- First was unearthed in Southern Africa. (Australopithecus africanus)
- Walked upright. Proportions of limbs were apelike.
- Relatively large brain.
- A. afarensis: Lucy. Dated at 3.18 mya, she stood upright and walked bipedally.
Ape-like above waist (small brain) and humanlike below the waist (walked erect). Proves human characteristics did not evolve all at one time. = Mosaic evolution.
V. Evolution of Humans
A.Fossils are assigned to the genus Homo if the following criteria are met:
- Brain size is 600 cm3 or greater.
- The jaw and teeth resemble those of humans.
- Tool use is evident.
B. Early Homo: Homo habilis "handy man": Dated between 2.0 and 1.9 mya.
- May be ancestral to early humans due to larger brain size, smaller cheek teeth, possibility of speech, and indication of tool use. May have been the beginnings of society and culture, if they hunted and ate together.
(Insert Homo Habilis picture / primatas.no.sapo.pt / http://primatas.no.sapo.pt/homem.htm)
C. Homo Erectus: Fossils found in Africa, Asia, and Europe. Dated between 1.9 and 0.3 mya.
- First H. erectus to be unearthed was in 1891, by Eugene Dubois.
- Several different species are included in this group, although all are similar in appearance.
- Compared with H. habilis, H. erectus had a larger brain and a flatter face. Nose projected, much taller. Were erect, with striding gait. Skeleton still showed some australopithecine features. Believed to have migrated from Africa into Asia and Europe.
- First hominid to use fire, and fashioned more advanced tools than early Homos.
- Believed to have used "home bases".
- Language and culture.
(Insert Homo Erectus picture / www.forcesitaly.org / http://www.forcesitaly.org/italy/immagini?M=D)
D. Evolution of Modern Humans
1d. Most accept the idea that Homo sapiens (modern humans) evolved from H. erectus. (Mader 482-484)
- Ability to interbreed.
- Little anatomical difference among populations.
- Little biochemical difference among populations.
- DNA and protein analysis show recent single common ancestor within 1 million years, perhaps only 200,000 years ago. (Frolich PowerPoint Slide 11)
2d. Multiregional Continuity Hypothesis: Belief that Homo sapiens evolved in several different locations. (ie. Asia, Africa, and Europe.)
3d. Others argue that it is unlikely that evolution would have produced essentially the same result in these different places. They suggest the following theory:
4d. Out-of-Africa Hypothesis: Proposes that H. sapiens evolved from H. erectus only in Africa, and thereafter migrated to Europe and Asia about 100000 years BP. This hypothesis suggests that we are more genetically similar than the other hypothesis, and this is the more accepted hyposthesis of the two.
E. Neandertals:
- First Neandertal discovered in Neander Valley, Germany, approx. 200000 years BP.
- Massive brow ridges, and their nose, jaws and teeth protruded far forward. Low forehead, lower jaw lacked a chin. Brain was slightly larger than modern humans. Heavily muscled. Lived in Europe and Asia during the lst ice age.
- Culturally advanced. May have built houses when not living in caves. Manufactured a variety of stone tools, including spear points. Hunted bears, woolly mammoths, rhinos, etc. Used and controlled fire. Buried their dead w/ flowers. may have even had a religion. Capable of thinking symbolically. (Mader 485)
(Insert Neanderthal and Modern Human Skulls Comparison picture / Frolich PowerPoint Slide 13)
F. Cro-Magnons: Oldest fossils to be designated Homo sapiens.
- Named after fossil location in France.
- Believed to be the modern humans who entered Asia and Europe from Africa 100000 years BP.
- Thoroughly modern appearance.
- Did not interbreed with Neanderthals, but seemed to coexist.
- Made advanced stone tools, including compound tools.
- May have been first to throw spears, and were accomplished hunters.
- Culture included art.
(Insert Cro-Magnon Skull picture / www.skadi.net / http://www.skadi.net/forum/showthread.php?t=11043)
G. Human Variation
1g. Widely distributed about the globe. Different ethnicities.
- Could be due to environmental adaptations. (ie dark and light skin)
- Bergmann's rule: animals in colder regions have a bulkier body build.
- Allen's rule: Animals in colder regions have shorter limbs, digits, and ears, to help regulate body temperature.
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