if that's the picture they are painting, they are quite wrong.
we don't evolve things for a "need" per se. It's not like I think, hey, I need a more effective digestive system so I can digest cellulose, and then go out and do it.
evolution is not directed in that sense.
I watch discovery, and national geaographic explorer, and they mention how these species gorws big teeth so they can eat, and that species grows wings so they can fly, and the like.
Something tells me you're wrong on what they're telling, but hey, the next time you see a program that says this, give me the name of it and the station so I can check it out.
And we're getting quite off topic
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