Quote:
Originally posted by Sly@Mar 27 2005, 04:51 AM
Scrambling up existing gene code will not give you something totally new.* A turtle may be born with two heads, a cow may be born with 5 legs, or a person may be born with 11 fingers. But there's no new information added.
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It seems to me, you consider evolution to be something you could see in a cheap sci-fi movie.
The fifth leg of a cow would not be new information - you're right!
But mutation is not just the visable change of form.
The fifth leg would mean that somwhere in the dna "blueprint" there was a mistake - so an extra limb grew. This mistake could be different as well. This cow could grow fangs. This would still make it a cow, but it would probably die - its teeth would not be apropriate for chewing grass. But if this cow would start eating meat (let's say would start attacking sheep) the fangs would come in handy. So the next step would be a fanged cow with the ability to (let's say) jump - to catch the pray easier. This would change the outlook of the cow. The hind legs would have to be stronger (if none of the cows would mutate that way this breed would die off). Next the cow would have to become less wounrable (the udder is to exposed). By this point you'd get a cow able to sit down (because of the change with its hind legs; it would have fangs; would eat meat - this would change it's intestance - no more 9 stomachs; this cow would have small udders and would give far less milk - also the calf could hurt the mother cow if it had fangs; the tail would be in a way - so it would have to disapeare; probably the shape of the head would change,...). So in the final stage that would not be a cow anymore. It would stop being a cow when it could not produce off spring with a normal cow - they would be incompatible. If all the evolutionary brakes would be in hte favour of the mutated cow - this could happen within dozzens of generation (and that's extremely fast).
But there are better chances that the first cow would not survive.
So just mutating isn't enough. It's when a series of small mutations (adoptations) take place and they all benifit a specie that real evolution takes place.
This is fairly common with single cell organisms - every change that happens happens within that cell and the mutation is caried to all the offspring (unless the first cell dies before spliting in two). But with more complex organism this form of mutation takes that much longer, most of mutations don't contribute to development of the race...
EDIT: Oh and about the DNA information...
There are only 4 building blocks of DNA. So a germ has the same four blocks as a human. It's the countless combinations (there is no limit to how many blocks are added to a string of DNA) that produce something new.
One stone is just a stone - million stones can be The Great Wall of China or countless amunition for a kid with a sligshot (OK maybe not the best example...).