Evolution and humans: big brain size uses energy (Evolution)

by dhw, Monday, November 06, 2017, 13:03 (2572 days ago) @ David Turell

dhw: Some folk might say that 23 million years ago a pre-human “obviously” descended from the trees and indulged in a degree of land-dwelling that changed the form of its spine.
DAVID: Not likely. This was an ancient monkey followed by other species of monkeys with a slight change in one lumbar vertebrae.

I don’t know what this implies for your hypothesis. Are you saying that 23 million years ago your God personally dabbled or preprogrammed a slight change in one lumbar vertebra for absolutely no reason? Or to “prepare the way” for Lucy some 20 million years later? If not, what is your point?

DAVID: Lucy obviously lived in and out of trees which fits your suggestion. But silverbacks and other great apes have done that for centuries without change. Lucy was something very different. God at work.

Why do you think every species of ape should have turned into humans? They have managed perfectly well as apes (at least till we came along), or they would have died out. Common descent means all species have branched out from earlier forms. It doesn’t mean every other form had to go extinct or to change into an ape and then into a human.

DAVID: First, you propose the early forms tried to think, and epigenetically forced an expansion of the brain. At a time when they did not know what they did not know, and lacked the capacity of imagining future possibilities.

dhw: What makes you believe that early forms couldn’t think? We have countless examples of our fellow animals solving new problems (and even making tools, although theirs do not require abilities beyond their existing physical capacities), so why shouldn’t pre-humans have had the same ability? No organism knows how to solve a problem before the problem arises, or before it has actually worked out the solution!

DAVID: A non-answer. They could conceptualize to a certain level of compexity at each stage. The artifacts show what they could think of, and artifacts advance with jump in brain size.

Yes, they could conceptualize, i.e. they could think (not “try to think”) of things that had not yet existed, i.e. were not yet known, so the artefacts do indeed show what they could think of. It is the implementation, not the concept that requires the jump in brain size. Concept first, then expansion if the brain is not already able to accomplish the implementation. Just as later the Indian women’s brains had to rewire in order to implement the concept of reading, instead of your God doing the rewiring first.

DAVID: But the skull as bone is a different type of cells. Did the brain cell committees tell the skull cell committees what to do?
dhw: All anatomical changes require cooperation between DIFFERENT cell communities. [...] Whichever way, the different cell communities must cooperate, whether on a small or a large scale. According to you, they can do it by themselves to shrink the brain, but they can't do it to enlarge the brain.
DAVID: You struggle to have cell communities doing their own thing, and bring in God to give them a mechanism to do so on their own, so He is never directly in charge. Intellectual side-step. If God created the universe, started life, managed evolution, then of course He speciated. As an agnostic you like to dabble a toe in holy waters.

You have already agreed that they do their own thing when changes are epigenetic and also when the brain shrinks. If I “bring God in…” as a possible inventor of the mechanism, how is that different from your “bringing God in” to invent a programme for the whole of evolution or to keep dabbling? “Directly in charge” is an “intellectual sidestep”. If God created the universe, life and the mechanisms of evolution, that does not mean he had to direct every step of evolution, every lifestyle, every natural wonder. Just as – according to you – he gave humans free will, he could have given organisms the means of inventing new forms for themselves, i.e. deliberately sacrificing control, though he could take it again if he wished. My agnosticism has absolutely nothing to do with it, unless you think that the only person qualified to talk about God is someone who shares your beliefs and non-beliefs (since you reject most religious concepts of God).

Dhw: As a matter of interest, do your ID friends insist that their God fiddled with ape anatomy before apes left the trees, designed eight stages of pre-whales before they entered the water, and planned weaverbird’s nests, toxin-swallowing snakes and skull shrinking shrews in order to keep life going until he could produce Homo sapiens’ brain? A simple yes or no will do.
Your answers so far have been: “Generally, yes. They (ID-ers) believe in planning and design.” And “It fits their theories.” And now: “They fully believe in prior design.”

“Prior design” of what? Everything listed above, as you believe? A simple yes or no will do.