Evolution and humans: big brain birth canal (Evolution)

by dhw, Sunday, October 28, 2018, 11:21 (2216 days ago) @ David Turell

dhw: I don’t see how Daddy’s genes would have dictated the expansion of the birth canal, but of course the fetus and Mummy must cooperate, and the cooperation between cells is entirely to the point.

DAVID: You have forgotten that baby and Mum are totally different individuals. Their DNA's cannot cooperate, but it known that the placenta does communicate with the forming fetus. Nothing to do with skull size.

How does this prove that Daddy’s genes dictated the expansion of the birth canal? I am suggesting that if the fetus had a larger skull, the birth canal would have had to adapt to the size of the skull. But you are right, the cell communities of the fetus would not cooperate to change Mummy’s birth canal– it is her cell communities that would have to adapt to the new challenge.

DAVID: Certainly God got his desired big-brained human by enlarging the birth canal.

dhw: I would have expected it to be the other way round: that the big-brained human fetus required the enlargement of the birth canal, but if you think your God enlarged the birth canal and this caused the expansion of the brain, so be it. I don't know why you think the transitional form proves that your God preprogrammed or dabbled the anatomical changes in advance.

DAVID: I said nothing of the sort. The larger brain required the larger skull and larger birth canal.

So God did not “get his desired big-brained human by enlarging the birth canal”. The larger birth canal was required to accommodate the larger brain.

DAVID: It all had to be designed and coordinated so everything fit as enlargement progresses.

As I wrote, “neither of us is in a position to explain the details of the timing or the process through which the cell communities cooperated to expand brain, skull and birth canal”, but you believe it was all preprogrammed 3.8 billion years ago or dabbled, and I suggest (theistic version) that your God may have given the cell communities the ability to work it out for themselves. “Same process: different hypotheses concerning how your God may have done it.”

dhw: The mystery is why your God would have personally preprogrammed or dabbled all these different hominins (not to mention whales and elephants and the duckbilled platypus) if his prime purpose was to produce the brain of Homo sapiens. I am not in the least worried about time intervals. I am worried about the illogicality of your suppositions, and I do not accept that we must abandon all sense of logic just because you would rather believe your God doesn’t think like us. Maybe he doesn’t think like you, and your suppositions are inaccurate, and his purpose and method are perfectly in keeping with human logic.

DAVID: It is obvious from the record that evolution took quite awhile. You are upset that your version of God wouldn't act like you ( a human) would. That is why it is silly to analyze Him like a human personality. He isn't human. His mystery is not the mysteries you concoct from your human reasoning.

Evolution has taken approx. 3.8 billion years so far, and I have no doubt that it will continue for millions/billions of years to come! I am not in the least upset. I simply challenge your claim to know that your God’s prime purpose all along was to produce the brain of Homo sapiens. I have proposed a different interpretation of his purpose, which even you have admitted fits in perfectly well with the history of life as we know it, but which upsets you because it does not correspond to your own illogical interpretation. And so you would rather not talk about the purpose you constantly refer to, on the grounds that you know you are right, and therefore God thinks with the same illogicality as you. Maybe he doesn’t, and your interpretation is wrong.