Evolution-Final Blog

When we first started out evolution section, all I really knew was what people have said and I saw on TV, where they said we evolved from chimps. As I said originally, I still don't believe that we evolved from the chimpanzee. I have gotten a better understanding into what has happened to us though, I believe that early humans were just like us but with diseases that we don't see as much in today's world. So to sum it up, I don't really believe we as a species have evolved at all but we have just had new advances in the world around us.

My Beliefs in a Cladogram

A cladogram shows the connection between species and branches them off into group based on what they have in common and they go back to a common ancestor. If we would make a cladogram based on what we used to believe, that humans evolved from chimps, then we would come off a branch directly from the chimpanzees. This is not what I believe happened at all, I don't personally believe that humans ever evolved, I believe that early humans just had different diseases and nutrition problems that caused them to look how they did and those just don't show up as often in modern humans. So if I made a cladogram off of my beliefs then chimps would be on their own branch and humans would also have their own branch with very little connection between them.

Evolution Tree

After doing our skull lab, we did a evolution tree as a class. We came up with a tree that had the modern chimp on it's own branch and modern humans on the other side on another branch. The human branch started with the Australopithecus, which went to the A. Africanus and the A. Boisei. Then were the Neanderthals and Homo Erectus. Then came the modern humans and Cro-Magnon man. This tree was supported by the discoveries we made when we studied the skulls of these species and put them into groups by similarities in features.

Chimpanzee or Gorilla

           Today we did a lab where we used paperclips to symbolize DNA strands of one human gene, one chimp gene, and one gorilla gene. The lab shows us that we are closer related to the chimpanzee, which is what people who misunderstand evolution would tell us. In reality we aren't related to either, we just have a common ancestor that is closer to us than that of the gorilla.

           Chimpanzees are not a direct ancestors of humans as many people would say evolution says. The reason people say we are related to chimpanzees is because they think humans look like them, which is somewhat true with the forehead but in reality we don't look like them at all. We may have 98% of the same genes as them but we also have 50% in common with a banana and I know for a fact that I am not directly related to a banana. So even though we have a lot of DNA in common with chimpanzees and gorillas, I don't really believe that we are directly related to them.

A case of co-evolution

This article said that species evolve together, and in competition. It says that as a species becomes better at escaping or resisting predators, those predators also develop new skills and evolve to be better suited to catch their prey. As this occurs those "prey species," continue evolving to avoid these predators. This goes back to that struggle for existence that occurs in the environment. They used the example of water fleas and the parasites that infest them, every time the parasite evolved new ways of infesting and harming the fleas, the fleas matched the parasite with a new way to resist the parasites. I agree with this theory because if predators didn't evolve with their prey, then we would have overpopulation of species as their predators would not be able to keep a equal level.

Bright vs. Drab

The other day we were talking about bright guppies compared to drab colored guppies. When there were a small amount of predators the bright guppies thrived because they didn't get eaten by predators and they could find mates easier than drab colored. When there were a lot of predators the number bright guppies decreased because the predators singled them out and there weren't enough left to reproduce to keep a steady number and the drab guppy numbers increased. This shows that certain traits are good for certain environments but bad for other environments.

Natural Selection

Charles Darwin said that the evolution of species occured because of natural selection. Natural selection is the trait being passed down and eventually making those lucky animals to survive because of that trait. Natural selection gives the variation and death that is necessary to life. That variation either causes certain animals to survive and compete better in the certain environment while the other animals are more likely to die off which will eventually eliminate the weak trait.

Evolution of Evolutionary Theories

The first evolutionary theory was in 1809 by Jean Lamarck. Lamarck said that the reason species adapt is by a muscle memory and that change happened to individual animals and not a whole species. In 1858 Alfred Wallace came out with his theory that put Lamarck's theory to shame. He said that in order for an animal to survive they must be the strongest, fastest, and healthiest species around. He said that in order for evolution to occur there had to be the death and eventually extinction of weak species. In 1859, Charles Darwin came out with his theory that was very similar to Wallace's theory but somewhat pollished. He said that the gene was already present in the descendants of the species and it just reappeared and was the best adaption.

Micro vs. Micro

Micro Evolution is the change within a species and macro is the change from species to species. Evolution doesn't just happen over night, it takes a long period of time and you won't see a difference between offspring and another offspring but from generation to generation.

Evolution-First Take

All I really know is that people say we were once monkeys and evolved into what we are now. I don't believe this though. To me evolution is the progressive change we have undergone that made us what we are now.