On Monday, August 23, 2021 at 9:38:49 AM UTC-4, littor...@gmail.com wrote:

Francesca's view:

The way I see it is that pronograde primates evolved into the orthograde, tailless apes in the early Miocene (25-28 Ma), in order to climb vertically up/down tree trunks to reach foods nearer to the ground, most likely in, or close to, water. If we

consider that in the early Miocene, Africa and Asia were far more humid than today and water was practically everywhere, it's not so much that they descended to the 'forest floor' as that they almost invariably would have descended to mangrove swamps,
gallery rivers, or forested lakes, and this is supported by the locations of the fossil finds for species like Morotopithecus, Ugandapithecus, and even Proconsul. There would have been no incentive for them to descend to savannah plains or open areas. If
the richest pickings (fruit, leaves) were growing at the water's edge, or even straight out of the water, they would have descended vertically, their feet reaching the water first. Females, with infants clinging to their chests or backs, would have had
even more incentive to remain upright, while wading/reaching out for the fruit. Then they would have sprung up into the trees again for safety.

This is what Marc means by 'aquarboreal' apes, and if offers the best explanations for why they lost their tails, became larger in size and shifted from horizontal to vertical locomotion.

The next stage of aquarborealism was the mid MIocene (16-12 Ma), where the majority of ape/hominid/pongid fossils are found in Eurasia, and signs of at least partial bipedalism + limb-clambering locomotion exist in many fossils (eg: Danuvious,

Oreopithecus, Ouranopithecus, etc.). They could suspend from the branches, but there was no evidence they were brachiators. Again, the climate in Europe until the Vallesian was very humid and there was a lot of water everywhere, (most of central Europe
was under the Tethys Sea) and again, these fossils have all been found in river or lake beds. This indicates that they were still all 'aquarboreal', living in trees by night but descending to watery environments during the day to forage. Then the
Vallesian Crisis (c.11-9 Ma) changed the climate drastically, the water dried up, the forests dwindled, the remaining trees were hard-leaved, the grasslands took over and many of these species went extinct, bar a few late surviving hominids in southern
Europe (Oreopithecus, Ouranopithecus, Graecopithecus). In order to survive the loss of these forests, these already partially bipedal apes took to the rivers and lakes and eventually the coasts and adapted to a foraging watery existence. At this point
they lost the 'arbor' but kept the 'aqua'.

By the time the Salinity crisis started (late Miocene, 5.7 Ma) we know that there were at least some (probably) fully bipedal hominids on Crete, an island that had separated from the mainland a few million years earlier, and the tracks they left at the

water's edge would support they foraged coastally, and I would guess had already started to lose some of their fur by then. The MSC of course rejoined Crete to the mainland and, as the water became brinier and evaporated faster, they would have migrated (
not necessarily the Cretan population, but any southern European surviving hominids, perhaps closely related or similar to Ouranopithecus or Graecopithecus) around the Anatolian coasts, or over landbridges to the Libyan / Nile Delta river systems, as did
many species of fauna (elephants, hippos, etc...) back towards Africa. (One group that made it back to Africa after the Vallesian but prior to the MSC would have been G).

Then, at 5.33 Ma, the Zanclean Flood came rushing in, cutting off those that hadn't yet crossed to Africa at the top of the Red Sea in the space of a couple of years, and stranding a bunch of hominins on the Arabian plate / Red Sea coast, while their

brothers and sister hominids that made it across, went on to become the African fossil species that we know about. Sea levels were 30 meters higher than today. (Incidentally - or perhaps fatefully - 5.3 Ma is the closest and best estimate so far given
and agreed on by most scientists as the date of the Pan/Homo divergence due to genetic evidence). Pan made it across. Homo didn't. Pan, given the option of returning to coastal forests, mostly did so. Homo had no trees. The choice was only between barren,
arid desert or a very resource and nutrient rich coast.

When the Pliocene ended, 2.6 Ma, waters receded, land bridges reappeared, and Homo, now very different from his Pan cousins and far more aquatic, was able to set off on his migration journey around the world, as evidenced by H. erectus fossils from 2.1

Ma in China and 2.04 Ma in South Africa.

This is very close to Elaine's original vision except for a few differences. She was thinking of Africa and she thought the aquatic part only happened to Homo, but she did think that a change in climate and a dwindling of the forests forced our ape

ancestors to the coasts / beaches where they gradually became bipedal, furless, etc. What is difficult for most people to grasp is that the GPH group was already an aquatic vegetarian wader, the PH group was already bipedal and semi-furless, clam-eating,
possibly tool-using, but then only H carried onwards towards full aquatic adaptations while G and P returned to the forests, regrew their fur and dropped to their knuckles.
-
Not a single reference to shelter. IOW, Mermaid fantasy, a very common fantasy among AMHs who always sleep in permanent rectangular shelters surrounded by others in similar shelters. Tunnel vision & lack of real life experience.

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)