coelacanth
Member
B.A.C. said:What specifically are you speaking of that will never happen? Speciation? What kind of changes would have to take place for you to call it a "new species"?
Well, for one thing Scientists can't even define what a species is, unless there has been a recent development. Secondly, we have never seen a new "kind" of animal arise from an existing "kind" of animal. I think that's pretty clear, no?
The ambiguity of what a species is arises mainly from biodiversity that is ever changing and our feeble attempts to categorize it into nice and easy little boxes - boxes that nature is under no obligation to fit itself into.
And, no. It's not clear at all. "Kinds" is far more ambiguous than the rigourous definitions laid out for various species concepts, but are we narrowing it down to the animal kingdom for our purposes here? How much change would it require to meet your criteria for a new "kind"? Separation of a population into filling different niches and no longer naturally interbreeding? Some arbitrary amount of morphological change? Inability of the descendants of a population to interbreed due to prezygotic or postzygotic barriers to reproduction? Some defined percentage of genetic change within a single population as compared to its ancestral population? Other things? Some combination of these?
Quite alright. This was a main part of my objection to the lack of clarity.B.A.C. said:Yes I did inadvertently contradict myself,
I'm afraid I may have to respond to the rest later. I've been overwhelmed with work... always just seems to keep piling itself up...