Miscellany (General)

by David Turell , Thursday, May 20, 2021, 20:18 (1281 days ago) @ dhw

Bird brains’ similar neurons

dhw: [edited for brevity] More silly straw men! The absurdity has nothing to do with your belief in God but lies in your belief […] that all life forms etc. were “part of the goal to evolve [= specially design] humans” […] [although] you agree that "extinct life has no role in current time", and past food bushes were for the PAST, not for the present.

DAVID: The bold is your silliness that evolution is not a continuum of increasing complexity. What you quote is true fact when interpreted properly.

dhw: Of course the bold about extinct life and food bushes is true, and it contradicts your belief that your God designed every past life form and food supply history as “part of the goal of evolving [=specially designing] humans” and their food supply. I keep agreeing that evolution is a continuum, but the continuum is the branching out from the roots of the bush to countless branches of life forms, only one of which presents a single line from bacteria to humans. The increasing complexity is not confined to that one line. Please stop leaving out those parts of your theory that make it illogical.

Of course one line becomes humans. The bush supplies our huge population the required food we need, all logically presented before.

Different types of neurons
DAVID: What this means is that when we discuss as 150 cc enlargement from erectus to sapiens we cannot know if some different kind of functional neuron was added to sapiens. So we know quantity but not true quality of the addition.

dhw: I suggest that the addition of functionless neurons would have been pointless. Common sense alone suggests that new neurons would have been needed to fulfil a new requirement.

DAVID: I didn't say 'pointless'.

No, I did. What would be the purpose of new neurons if they had no purpose???

DAVID: What we don't know is if sapiens some different specialized neurons of greater reasoning capacity than erectus. 150 cc enlargement doesn't tell us.

dhw: I agree that we don't know what new function the new neurons performed, but I can only repeat the question above. I find it hard to believe that new neurons were added to the brain for no reason.

The extra ones sapiens got caused the present civilization to appear.

Species differentiation
"If you ask ten biologists, you will get twelve different answers," Sukumaran said." (DAVID's bold)

DAVID: We don't understand how speciation happens, and this problem of minor differences cannot be decided by splitter or lumper dispositions of researchers. Darwin's finches come to mind, all based on beak size.

dhw: Darwin also discusses the “difficulty of distinction between Varieties and Species” and I agree with you: variations in beak sizes do not solve the problem of how “species” – as opposed to varieties – evolve. I think “organisms capable of interbreeding” may be the closest we can get to a satisfactory definition of "species".

Hybridization is certainly one way.