Tree of life not real (Introduction)

by dhw, Sunday, February 16, 2014, 12:17 (3935 days ago) @ Balance_Maintained

TONY: My point is we do not have this gradual progression from less complex to more complex. Where complex creatures exist, they exist, with no obvious reliable precursors, and they exist alongside simpler forms already existed and did not grow significantly more complex. At least, we have no definitive evidence that one creature grew into a more complex one, only speculation. I am asking what happens to this train of thought if we remove the speculation about one organism metamorphosing into another organism, something which we have no definitive observations of, and simply look at the evidence for what it actually is instead of what we want it to be? Would our perception about the whole thing change?-The alternative which I presume you have in mind is separate creation. "Definitive evidence" is perhaps the key expression here. We have no definitive evidence for - or observation of - any form of life that does not descend from existing organisms (disregarding the very first living organisms, about whose origin we know nothing and therefore speculate endlessly). The observation that life descends from life is the basis of "common descent", which in turn is the basis of evolution. The alternative to one organism metamorphosing into another organism has to be not just one original form of life but billions. Even if I put on my theist hat, I would find it hard to believe that God would go to all the trouble of specially creating billions of forms the majority of which literally came to a dead end.
 
From our past discussions, I know you would like to restrict your God's creativity to a few "kinds", and your reservations about defining speciation seem to me to be fully justified ... no-one has ever come up with a satisfactory answer ... but if you are prepared to allow Nature to produce its own variations on the original kinds, where do you draw the line? An evolutionist is prepared to allow Nature to produce innovations as well as variations. An atheist evolutionist will no doubt point out that the lack of "definitive evidence" concerning one organism metamorphosing into another scarcely justifies belief in organisms starting all over from scratch (no definitive evidence or observation), let alone belief in an unknown and unknowable divine power producing new organisms out of nothing (no definitive evidence or observation). In the end, everyone has to opt for what seems to them the most likely of all the speculations, or perch on the picket fence. I myself opt for common descent, but remain open as to how the process of evolution originated and how it actually works.