Science news: Brain plumbing, nekkid Lucy the Australopithecus, more

I've read recently that the amyloid plaque idea of Alzheimer's is not on the most solid ground, but it's verboten to question it, let alone offer alternatives, in serious research journals.

Well, what if it's partially right but not fully so?

This idea, that the brain's glymphatic system flushes brain waste during non-REM sleep, including but not limited to, amyloid plaque, would be one idea. In this case, then, two people with similar daytime levels might differ on Alzheimer's symptom degrees, or even whether they have it or not period, depending on whether their brain plumbing is working well or not.

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An interesting piece here, ostensibly about Lucy the Australopithecus afarensis, but in reality about body-draped reconstructions off fossil bones of ancient hominins in general. Per the story, to use the old Texas word deliberately, Lucy, and her ilk, actually might have been more nekkid than they've been portrayed. Linked in the piece, the author, a philosopher, notes that the coevolutionary history of humanoids and humanoid-targeting body lice says that not only was Lucy nearly nekkid, her ancestors may have been nearly hairless as much as 1 million years earlier.

Stacy Keltner speculates that shame over nudity arose to reinforce pair-bonding by trying to shame actual or would-be cheaters. The idea sounds interesting, but it also sounds like it involves some backward-reading Ev Psych. Indeed, Keltner cites an evolutionary anthropologist. Nudity and nakedness, if you will, are indeed not the same. But, the speculation as to why nakedness became, essentially, shamed into nudity still seems like awfully thin ice. To put it another way, it looks like a somewhat self-referential take, unable to escape our 20,000? 50,000? years of post-nudity framing.

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Related somewhat to Lucy, though not on the development of nudity and shame?

Carl Zimmer has reporting on human fossils in Tibet confirmed to be Denisovan. The age range is the biggie. It's from 160,000 years before present, confirming how early Denisovans split off the Homo family tree, to just over 30,000 years bp, including evidence of their interaction with Homo sapiens.

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Another Zimmer story notes that new research indicates language evolved primarily for communication, and NOT for thinking. Fun sidebar? This is another overturning of Chomsky's claims about language. (I can't say "research," since Chomsky did basically none.)

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It sure would be nice if NASA could work with the Chinese Space Agency and see some of those far side of the moon rocks that the Chang'e 6 spacecraft brought back to earth. But, because of US Congressional tribalism on China that predates COVID by nearly a decade, US law says it can't.

Meanwhile, bringing back 2 kilos of rocks by unmanned voyage? The American Cold War-based rationale for manned lunar missions (and a manned Martian mission beyond that) continues to lose more and more steam.