by Warren » Jul 18, 2002 @ 8:33pm
Moose, evolution does take extremely long, but it really works in spirts. If there is an extreme environmental change, then the organisms will evolve to fit the change very quickly, when there is no change, evolution is very slow, so evolution is not linear. As for going from fish to man, it went fish to reptile to mammal to man. A lizard and a fish are similar, and there are fish with real lungs that can walk on earth. The evolution chapter in my biology book was really good, it even showed how bacteria evolved from natural organic material made from lightning and atmospheric matter. Evolution is slow, the Earth is 4,500,000,000 years old, while organisms have been around for 1,000,000,000, and most of that time was just bacteria. When bacteria evolved into eukaryotic cells, they quickly were able to make the first multicellular organism, and evolution exploded. Small animals started appearing, and plants were common (conifers and seedless vascular, along with bryophytes). After a few hundred million years (which is a while...), dinosaurs were abundant (there were some vast extinctions even before the dinosaurs, mostly of plants). The dinosaurs were around for a really long time, then BOOM! 65 million years later, we're here, because the mammals survived the cold (warmblooded), like the mamoth and sabor tooth tiger. After more evolution, people came. You say "well, how can a human come for a monkey?" well, how can a bird can from an amphibian? Speciation is very diverse, all thanks to evolution and Darwinism. It isn't hard to make a new species, look at the Galapagos Islands, all new species because of geographic isolation.
As for evolution being "guided", it's not complex, why do we have fingerprints? Because people way back that didn't, would be able to hold stuff, so they didn't survive as well.
Evolution does take a long time, think, we've only been here for 20,000 years, but organisms have been here for over a billion! That's 50,000x longer! A lot of things happened before us.