The question is:
What exactly is Evolution and why do people care about it so much?
I heard a plethora of things about Evolution but what exactly is it? Why is it so vital for some people?
http://answers.yahoo.com/question/index;_ylt=Aj1m.kK8l66d1ZusFLoUmQ0jzKIX;_ylv=3?qid=20081112175258AAsrEff
My answer was too long so Yahoo wouldn't post it. So I copy and pasted it here and I intend to link to this blog entry in my new answer.
None of it true, I'm sure. Evolution is the theory that attempts to model how the fact of evolution (descent with modification) has resulted in the observed diversity of life on earth. The theory of evolution is based on observations by creationists like Linnaeus who noticed that all of life seemed to be classifiable in a sort of tree of related kinds. This was the beginning of our modern taxonomic system for classifying species. The observations between fossils extinct species and living species helped to give the impression that extinct animals are somehow related to now living species.Then along came Darwin who took this observation and observations from animal husbandry, namely the fact that we pick animals of the same species with traits that we like and breed them together to mold those traits in almost an art form. He talks about how expert pigeon breeders could even sculpt the shape of the beaks in a relatively few generations. He argued in favor of a mechanism of inheritance and then he applied this observed "artificial selection" to certain similar aspects of nature. In artificial selection it's us humans who decide which of our stock of animals are fit to breed, but in natural selection it becomes the specific survival requirements of nature that determine which of the stock of animals is fit to reproduce.Darwin also hypothesized the existence a mechanism for mutation, which would allow new inheritable traits to be introduced into the stock of animals. This was all long before we knew what the inside of a cell looked like. This was before we knew about genes and genetics so Darwin had no idea what the mechanism might be or how related biology was, on the cellular level to other existing disciplines such as chemistry.Darwin's idea was that natural selection definitely accounts for the observed variation within species in nature as artificial selection accounts for how a skilled breeder can sketch out a beak for a pigeon and in a relatively few generations breed a pigeon with that beak. He went a little further with this, though, to argue that, because it's also observed that all of the organisms alive and extinct share features that they may share a common ancestor and that all of the current species may have evolved through the mechanisms of mutation, inheritance and natural selection.Interestingly enough this hypothesis has only been confirmed through the discovery of the complexity of cells, genetics, biochemistry, embryology, etc. The phylogenetic tree is the tree that shows the evolutionary pathways of modern species from the very first cell. The phylogenetic tree's are developed by taking species that share characteristics and if they share all characteristics they are the same species, if they share more then they share a common ancestor, maybe not a unique common ancestor, but a common ancestor none the less. The more characteristics two species share in common the more recent the common ancestor. This is also confirmed by genetics, which shows us that two species that are phylogenetically similar are more genetically similar than two species that are less phylogenetically similar. This works because of the principle of inheritance. We can only inherit features that are present in our gene pools. So if you ever find an animal with a plant cell wall or chlorophyll you may have just falsified the entire theory of evolution. Those features are not shared by any common ancestor to animals and plants. They evolved independantly in plants long after our common ancestors branched, so they aren't in our shared gene pool, and mapping the gene pool has confirmed that they are indeed not in our genome. If you found haemoglobin in plants it would be the same situation. New features will evolve in the gene pool and if they're useful they'll stick around, much the way chlorophyll was useful for plants and vertebrae was useful for...well a lot of animals, heh.That was a basic primer, there's a lot more left to learn on the subject if you're honestly interested. As for why it's vital, I am extremely sure that evolution is correct based on the mountains of evidence that I have read in favor and the complete lack from all available sources of evidence that it is not correct. So from that standpoint I see it as vital to our existence, if it's correct, but not in any way that matters as we're already here. On the other hand it's not vital in any other way. If you want to have a chance of understanding the world we live in learning evolution can help. If you just want to believe something for reasons irrelevant to what's true, by all means ignore evolution or believe it's false.
Oops...I took too long answering and the question became resolved...that's why I couldn't post my answer...I wish Yahoo would tell you that. The generic "Yahoo Answers is taking a breather" error is getting annoying.
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