Posted on 01/26/2006 3:31:41 AM PST by Pharmboy
There also isn't a theory that says they did.
For the life of me, I don't know why this basic concept is so hard for you to grasp.
I did not decend from my cousin. But my cousin and I had a common ancestor.
Those scholars who are interested in the history of the eugenics movement will find some arresting quotes in the fifth chapter of The Descent of Man. This chapter, titled "On the development of the intellectual and moral faculties during primeval and civilized times" provides source material for many of the eugenicist arguments. For example:
With savages, the weak in body or mind are soon eliminated; and those that survive commonly exhibit a vigorous state of health. We civilized men, on the other hand, do our utmost to check the process of elimination; we build asylums for the imbecile, the maimed, and the sick; we institute poor-laws and our medical men exert their utmost skill to save the life of every one to the last moment…Thus the weak members of civilised societies propagate their kind. No one who has attended to the breeding of domestic animals will doubt that this must be highly injurious to the race of man. It is surprising how soon a want of care, or care wrongly directed, leads to the degeneration of a domestic race; but excepting in the case of man himself, hardly any one is so ignorant as to allow his worst animals to breed. (Darwin, 1871, 1896, p. 133-134)
There isn't anything incorrect about what he said there. How it's applied is a matter of ethics.
People survive now with defects that would have killed us in a more primitive time. We certainly pass those defects on much more frequently now than we did when those defects would have killed us. We certainly have many diseases and weaknesses that are genetic. And a genetic predisposition to cancers in some families stops few from deciding to have children. Such predispositions to have cancer or bad eyesight would prevent any breeder of animals to decide not to breed a particular animal, but because it's not socially limiting, we are a society now where it is common to have genetic cancers and bad eyesight requiring glasses even as young children. Is that a good thing?
There was more but I'm busy at work and didn't have time to find it. However, I wonder if that is taught in schools as well.
But unless you can predict both the conditions and type of body, your statement is meaningless since it can account for any conditions correlated to any body plan...and you certainly can't reproduce such a scenario in the lab.
All you have really is unsupported conjecture...of, course, that's nothing new when it comes to the hard science of evolution.
A terrific example of "convergent evolution" (that is, different organisms "converge" toward a similar trait) is the fish form. Both teleost fish (salmon, tuna, etc.) and mammals (whales, dolphins) got to pretty similar body types because of environmental demands. Not exactly, though...whales tails are horizontal, fish vertical. It might have something to do with the need for the mammals to get to the surface often.
Nice get...
With no teeth, perhaps a carrion ripper...
mlc: What????
There are several classic examples of convergent evolution: Porpoises, fish, ichthyosaurs
Another is the saber tooth "tiger" (Smilodon) and an almost identical marsupial version (Thylacosmilids)
LOL!!!!!!!
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