from Sci.Bio.Paleo
Friday, October 4, 2019 at 5:04:21 PM UTC-4,
littor...@gmail.com wrote:
> Op donderdag 3 oktober 2019 07:25:32 UTC+2 schreef Daud Deden:
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> > > > > Selection of endurance capabilities and the trade-off between pressure and volume in the evolution of the human heart
> > > > > Robert Shave, Daniel Lieberman ... 2019 PNAS 116:19905-10
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https://doi.org/10.1073/pnas.1906902116
> > > > > Unlike other great apes, humans evolved multi-system capabilities for moderate-intensity EPA, but it is unknown if selection acted similarly on the heart. We present data from a sample of humans, chimps & gorillas, showing that the human (LV) evolved numerous features that help to augment stroke volume (SV), enabling moderate-intensity EPA. We also show that phenotypic plasticity of the human LV trades off pressure adaptations for volume capabilities, becoming more similar to a chimp-like heart in response to physical inactivity or chronic pressure loading. Consequently, the derived human heart appears partly dependent upon moderate EPA, and its absence (+ a highly processed diet) likely contributes to the modern epidemic of hypertensive heart disease.
mv: > > > > > This is a beautiful example of traditional anthropocentric just-so thinking, that apes leaving the forests evolved into "hominins"
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dd: > > Human ancestors left the forest CANOPY. Those that left the forest entirely always camped under trees eg. Khoisan.
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mv: > > > > > running bipedally over open plains: the authors assume that human ancestors initially hunted & gathered,
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dd: > > They did.
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mv: > They did not: they collected waterside & shallow-aquatic foods.
dd: That was part of their diet.
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mv: > > > > > and then try to collect data that fit this unscientific idea.
> > > > > In fact, their data (e.g. stroke volume, cardiac plasticity) are better explained by a littoral lifestyle (incl. wading bipedally & shallow-diving),
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dd: > > They did, mostly along shallow crystalline streams.
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mv: > Your "crystalline streams" might perhaps be late-Pleistocene in some populations,
dd: From Morotopith.
mv: but all data show that early-Pleistocene Homo dispersed along coasts, rivers & islands, from Java & Flores to E.Africa & the Red & Med.Sea.
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> > which they didn't even consider: early-Pleistocene Homo dispersed intercontinentally along African & Eurasian coasts, rivers & islands, collecting different waterside & shallow-aquatic foods, rich in brain-specific nutrients (DHA etc., absent in savannas).
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> > > > > Endurance Running Versus Underwater Foraging:
> > > > > An Anatomical and Palaeoecological Perspective
> > > > > Stephen Munro 2013 Hum.Evol.28:201-212
> > > > > The dominant theory of human evolution has long been that humans evolved as a result of leaving the forests and becoming better adapted to life in more open, arid habitats (terrestrial model). This idea pre-dates Darwin's ideas on natural selection, has never been subjected to rigorous scientific scrutiny, and is far less credible than the alternative model proposed here: that human evolution occurred as a result of adaptations to a littoral environment
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dd: > > Super-littoral
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mv: > Meaning "very littoral"?
dd: Littoral and beyond.
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mv: > > > > > in which ancestral populations for part of the time foraged under water for slow moving, immobile and sessile resources such as shellfish; dispersed around coasts; and moved up rivers to inland wetlands,
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dd: > > Crocs & apes at swamps, Homo was at shallow streamside.
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mv: > Early-Pleistocene Homo was littoral:
dd: Stream-side.
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