Evolution: whale adaptive losses and changes (Evolution)

by dhw, Saturday, September 28, 2019, 10:58 (1882 days ago) @ David Turell

DAVID: Interesting complex changes, and one can imagine some of these adaptations while learning to become aquatic, but note my bold. How does a whale learn to sleep with half a brain active while living in the water, without drowning during the process of adaptation? For me God prepared them.

dhw: Nobody knows, but I suggest that, as with every other adaptation, the cells worked out a solution to improve performance or to cope with new conditions. It’s not beyond the scope of reason that initially some whales did drown if they strayed too far away from land, and others swam till they found dry land to sleep on. Loss of melatonin would then be the result of training the body to do without sleep for long periods. But the eventual half and half compromise would be the solution that worked best and hence survived by natural selection. Certainly no more fanciful than your God preprogramming the first cells with the whole history of whale stages, bacteria solutions, monarch butterfly migration, weaverbird nesting etc., all to cover the time he’d decided to wait before pursuing his one and only goal!

DAVID: Your explanation tells us some just-so stories. Finding dry land does not explain what God must have programmed.

That is your “just-so story”, and I don’t know where you get your “must have” from! In any case, why is it “just-so” that initially some whales would have drowned but others could have found a place to sleep?

DAVID: How did whales tell melatonin to go away?

They didn’t. It went away of its own accord when its sleep-inducing properties were no longer effective or needed, just as the flipper would have lost its legginess, and the toothless whale would have lost its teeth.

DAVID: Same issue: why bother with whales in the first place? Answer, because they are a major part of the ecosystem of the ocean.

Every organism plays/played a part in every ecosystem extant and extinct. The question is why your God bothered if the only species he wanted was H. sapiens. But of course that is “explained” by your God’s inexplicable decision not to design the only species he wanted for 3.X billion years, and therefore having or needing to invent all sorts of organisms to eat or be eaten by one another in order to “cover the time”.