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Re: A Human Ancestor for the Apes?

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  • DDeden
    ... Excluding the extant sea turtles, saltwater crocs, marine iguanas... There have been a huge variety of marine reptiles, most of which perished along with
    Message 1 of 52 , Jan 2, 2008
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      --- In AAT@yahoogroups.com, "m3dodds" <dons3148@...> wrote:
      >
      > --- In AAT@yahoogroups.com, "DDeden" <alas_my_loves@> wrote:
      > >
      > > --- In AAT@yahoogroups.com, "m3dodds" <dons3148@> wrote:
      > > >
      > > > --- In AAT@yahoogroups.com, "DDeden" <alas_my_loves@> wrote:
      > > > >
      > > > > --- In AAT@yahoogroups.com, "m3dodds" <dons3148@> wrote:
      > > > > >
      > > > > >
      > > > > >
      > > > > >
      > > > > >
      > > > > > --- In AAT@yahoogroups.com, "DDeden" <alas_my_loves@> wrote:
      > > > > > >
      > > > > > > Thanks m3d for reviewing the small size of eosimias.
      > > > > > >
      > > > > > > At my blog, (noted earlier) you can see the size
      > > > > > > difference between frogs, one thumbnail size, the
      > > > > > > other much larger, these are concurrent. I assume
      > > > > > > eosimia had larger relatives concurrently.
      > > > > >
      > > > > >
      > > > > > Possibly. But we have to remember that mammals had only
      > > > > > began to reclaim the Earth, 45 million years ago ...
      > > > > >
      > > > > >
      > > > > > LiveSccience.
      > > > > >
      > > > > > "There was an increase in small and medium-sized
      > > > > > mammals in the first few million years after the
      > > > > > end of the dinosaurs, the researchers reported.
      > > > > > A second surge, from medium to large sizes, was
      > > > > > seen between 50 million and 40 million years
      > > > > > ago, they reported."
      > > >
      > > >
      > > >
      > > >
      > > > > Perhaps that explains the lack of large ocean tetrapods
      > > > > until the whales. For quite a while, the seas seem to
      > > > > have had a gap, from the extinction of cold blooded marine
      > > > > reptiles (pliosaurs, plesiosaurs, ichthyosaurs, mosasaurs,
      > > > > etc.) to the expansion of warm blooded marine
      > > > > mammals.
      > > >
      > > >
      > > >
      > > > Not sure what you mean ... DD.
      > > > Other than that the cetaceans, could be classed
      > > > as tetrapods that returned to an aquatic existence.
      > > > Would think though that the aquatic marine reptiles,
      > > > originated in the seas.
      > >
      > >
      > > Nope, they went from land dwellers to sea dwellers
      > > like whales did later.
      >
      >
      >
      > Reptile 'cetaceans' ...
      > When did they return to the dark depths?

      Excluding the extant sea turtles, saltwater crocs, marine iguanas...

      There have been a huge variety of marine reptiles, most of which
      perished along with the dinosaurs, others that had perished during an
      earlier extinction. Many gave live birth and all were air breathers
      AFAIK (like whales), none had sonar, many had large eyes, some had
      internal/external nostrils.

      There have also been semi-aquatic croc-like dinos. By the time of
      early whales/sirenians/marine sloths/aquatic lemurs, all of these
      (except the partly-marine penguin descendants of theropod dinos) were
      already gone AFAIK, leaving only sharks and fish in the pelagic seas.

      >
      > > > > Perhaps the large land mammals were all derived from
      > > > > semi-aquatic small mammals which improved their metabolic
      > > > > efficiency due to the ability to retain or reduce oxygen
      > > > > consumption, and then some returned to the land full time.
      > > > > Consider how many large mammals seem to have water-side /
      > > > > semi-aquatic roots: elephants, rhinos, sloths, boars,
      > > > > horses, hippos, okapi, gigantopith?, tigers... Many large
      > > > > extinct mammals shared similar features. Whales and
      > > > > manatees are both said to have developed about 50 ma
      > > > > around India.
      > > >
      > > >
      > > >
      > > > Possible they may have survived, in an semi-aquatic
      > > > niche, but in general mammals are said to have survived
      > > > the time of the dinosaurs, by becoming smaller and
      > > > living underground in burrows.
      > > >
      > > > A possible mammal ancestor ... (a very, very small one)
      > > > from a mere 200 million years ago, in what is
      > > > now China.
      >
      >
      >
      >
      > http://tinyurl.com/3beoer
      >
      > http://www.livescience.com/animals/ap_050929_oxygen_mammals.html
      >
      > ----------------------------------
      >
      >
      >
      >
      > > > > > Excellent ... DD
      > > > > > I was looking for a map, showing early primate
      > > > > > diffusion. This one does seem to indicate that
      > > > > > they would have had some considerable difficulty
      > > > > > reaching Africa ... Which would have been made
      > > > > > even more difficult if the ocean currents through
      > > > > > the Tethys, were flowing eastward into the
      > > > > > Indo-pacific ocean.
      > > >
      > > >
      > > >
      > > >
      > > > > Birds and bats ought to have been able to cross easily,
      > > > > terrestrials and arboreals would have had to wait until
      > > > > lower sea levels or tectonic uplifting or vegetal rafts.
      > > > >
      > > > > Note that the Turkey/Iran/Iraq/Syria area seems to have
      > > > > had a low land bridge of some type for a long time that
      > > > > has since crumpled up into mountains. Since that area is
      > > > > far north of the tropic coast of India-Sunda, effective
      > > > > bridging would only exist during relatively
      > > > > mild humid warm conditions, not cold/dry periods, but
      > > > > that is also when sea levels are high. (I think a lot
      > > > > of migrating birds use that route, perhaps their ancestors
      > > > > followed the Tethyan coasts.)
      > > >
      > > >
      > > > Land access between the two continents, seems to
      > > > have been difficult, if not impossible until about
      > > > 18 million years ago

      My guess is that it was not only a geographic separation, but an
      ecologic filter as well, where species crossing the islands had to
      evolve/adapt to a freshwater/saltwater and/or desert/arboreal switch.

      ... guess once the land bridge
      > > > was open, there was a lot of north-south migration
      > > > of terrestrial species.
      > >
      > > Yes. I was thinking of tethyan islands, rather
      > > than bridge.
      >
      >
      > Agree, island hopping was probably the only way across.
      >
      >
      > > > > > > You don't think our Homo ancestors did much
      > > > > > > diving, mainly beachcombing and wading in
      > > > > > > the littoral zone? Well we disagree on the
      > > > > > > extent and depth I guess.
      > > > > >
      > > > > >
      > > > > > We do agree on much, DD, but your emphasis
      > > > > > is on adaptations arising from being in an
      > > > > > from moving through water, whereas mine is
      > > > > > on the changes resulting from living near
      > > > > > an obtaining food, from water ...
      > > > > >
      > > > > > ---m3d
      > >
      > >
      > >
      > >
      > > Here I meant the Homo home base, not their entire
      > > territories, which may have been vast, depending
      > > on the size of the populations. Obviously the many
      > > handaxes found in the rift and coastal highlands
      > > indicate inland treks, but I see them as visits
      > > from the coasts.
      >
      >
      > It was more than visits, DD, they migrated and
      > settled inland (probably near large bodies
      > of water ... major rivers, lakes an
      > inland seas).

      In China, yes, inland rivers, however we don't know how many lived on
      the now-submerged lowland plateau (Hainan/Taiwan). We find bones or
      tools inland, the ones on the coasts of that period aren't known due
      to erosion, deposition, recycling.

      IMO the ones that permanently separated from the ocean eventually
      became extinct, they are not our ancestors but rather our ancestral
      cousins. Only those that retained a connection to coasts are ancestral
      to modern Hs.


      > > > > I include terrestrial & arboreal adaptations as well.
      > > > > I tend to limit them to <100m above sea level and
      > > > > <100km from seashore, including rifts and near-shore
      > > > > archipelagos, until dugouts allowed inland access.
      > > > > DD
      > > >
      > > >
      > > >
      > > > I would agree that H.s used dugouts, in their coastal
      > > > migrations, but H.e seems to have preferred a more
      > > > direct route east (an inland route),

      Perhaps along the northern rift valley towards Turkey and along the
      shored of the para-tethys eastwards, stopping at flint and basalt
      quarries.

      from the evidence
      > > > of their presence in the Levant(Jordan valley),Dmanisi
      > > > Riwat and China ...
      > >
      > > Yes, quite possible, though due to shoreline changes, I
      > > think coastal He migration is not unlikely. Whether He
      > > used primitive dugouts, I don't know.
      >
      >
      > There is plenty of evidence of H.e in China an Java, but
      > none on the Indian sub-continent, so I would say coastal
      > migration of H.e was unlikely ... they probably chose
      > the shorter and more direct route east(an west), the
      > inland route(probably following migrating herds)...
      >
      >
      > http://news.bbc.co.uk/2/hi/science/nature/6518527.stm
      >
      > http://cat.he.net/~archaeol/0001/newsbriefs/china.html
      >
      > http://www-personal.une.edu.au/~pbrown3/zhk.html
      >
      Not unlikely both, with only deserts, mountains, cold and seas
      preventing transit.

      >
      > Inland routes, east and west, were still major trade
      > routes at the dawn of recorded history ... such as
      > the legendary Silk road ...
      >
      > http://en.wikipedia.org/wiki/Silk_Road

      Which depended on water carrying technology and clothing and tents and
      unique goods to be exchanged.

      > > > Where you range over a wide period of time, DD, I find
      > > > two periods of particular interest....
      > > >
      > > > One before the emergence of H.e ... nearly two million
      > > > years ago, an two the emergence of the common ancestor
      > > > of H.n an H.s ... some 700,000 to 800,000 years ago.
      > > > Both appear to be influenced by time spent living and
      > > > foraging on the shore.
      > > >
      > > >
      > > >
      > > >
      > > >
      > > > Happy New Year DD, everyone ...
      > > > may 2008 be the year, AAT wins the argument.
      > > >
      > > > ---m3d
      > > >
      > > Cheers m3d
      > > DD
      >
      >
      > ---m3d
      >
      >
      >
      >
      >
      >
      >
      > ------------------------------------------
      >
      >
      > > > 22-12-2007 21:33, m3dodds <dons3148@> schreef:
      > > >
      > > >
      > > > Do we really need to consider turning everything upside
      > > > down by considering the existence of a human ancestor
      > > > for the apes?
      > > >
      > > > This suggestion definitely has the quality of blasphemy
      > > > against religious doctrine. It just feels wrong and goes
      > > > against our deeply held beliefs and understanding of the
      > > > world.However, this is exactly where the evidence leads.
      > > >
      > > > Aaron Filler, MD, PhD
      >
    • DDeden
      Review: bipedalism, float, Peruvian marine otter freshwater berry picking during rainy season? ... viable.
      Message 52 of 52 , Oct 4, 2008
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        Review: bipedalism, float, Peruvian marine otter freshwater berry
        picking during rainy season?

        --- In AAT@yahoogroups.com, "DDeden" <alas_my_loves@...> wrote:
        >
        > thoughts (gtg)
        >
        > Regarding the upside down flip from invertebrates to vertebrates,
        > consider the sea otter, in the absence of human influence, after
        > another 20-50 million years. People assume it would become more
        > dolphin like, but it is possible it could instead become even more
        > upside down, back floating, back stroking, back diving, until it's
        > entire physiology evolved so far as to make normal terrestrial
        > quadrupedal posture and locomotion impossible (even worse than true
        > seals). At some point a shift in the septum/spine process might give
        > advantage, and no disadvantage.
        >
        > Complexity is less significant than niche advantage.
        >
        > speculation:
        >
        > Monkeys could swim above/underwater (long tailed macaques, nasalis)
        > holding their breath (face first), but not float vertically plucking
        > food while breathing. So when wading, at a certain depth they must
        > switch to swimming dog-paddle, they cannot rest in water for more than
        > a few seconds. Therefore can't lose their fur coat, so no partly or
        > fully naked monkeys.
        >
        > Apes couldn't swim underwater, their air sacs inflate due to innate
        > anxiety/immersion (feet first), so they could float vertically
        > plucking food while breathing through their nose. So when wading, at a
        > certain depth they must switch to vertical floating with inflated air
        > sacs while nose breathing, using hands and feet to hold/pluck items
        > while at rest. They can rest for long periods while feeding in water.
        > Resulting in various levels of hair loss and slightly increased skin
        > fat. Bones would not have been dense.
        >
        > Coastal Homo derived from this early ape niche, but returned to more
        > monkey-like breath-hold diving for below-surface foods during the
        > switch from mangrove oysters/AHV/flotsam feeding to reef diving for
        > benthic molluscs etc. with fur loss, air sac loss, increased fat and
        > dense bones. The anxiety/immersion stress reaction (gasp) changed to
        > stronger divers reflex during breath hold, both while deep wading and
        > diving.
        >
        > In miocene wet forests/swamps/mangroves vertical
        > climbing/floating/wading would be an advantage, laryngeal air sacs
        > also, tails not so much.
        >
        > I tend to see all apes/Homo as having descended from coastal ancestors
        > with functional bipedal locomotion (siamang-like). Extant great apes
        > are remnants of previous expansions inland during mild climates and
        > were selected for inland life, becoming more quadrupedal as drier
        > periods occurred.
        >
        > Why do we differ from chimps? Chimps moved inland while air-sac
        > floating was still the norm at the coasts, before diving (facial
        > submersion) began; following streams inland and eating freshwater
        > crustaceans as well as fruits along the gallery forests (oddly
        > parallel to marine otters of Peru). Our ancestors did not move
        > upstream inland until thrusting spears were figured out (perhaps from
        > reef-hole spearing, parallel to female chimps spearing bush babies in
        > hollow trees), dug-outs allowed safer settlement.
        >
        >
        >
        >
        >
        >
        >
        >
        > --- In AAT@yahoogroups.com, "Elaine Morgan" <elaine@> wrote:
        > >
        > >
        > > ----- Original Message -----
        > > From: Marc Verhaegen
        > > To: AAT@yahoogroups.com
        > > Sent: Thursday, December 20, 2007 1:57 PM
        > > Subject: Re: [AAT] Re: A Human Ancestor for the Apes?
        > >
        > >
        > > Very original, logical up to a point, but I can't buy it because:
        > >
        > > 1. His star example of such a body-plan shift is right at the
        > beginning,a tiny animal in the ancient seas turns its anatomy upside
        > down, becomes the ancestor of the vertebrates while the others founded
        > the insects. That would work because in such a primitive creature
        > there was no difference to its survival chances which way up it was.
        > You can't turn a cockroach or monkey upside down. The more complex it
        > is, the less sweeping the change you can make if it is to remain
        viable.
        > >
        > > 2. This hox gene causes a complex set of changes to the lumbar
        > region of the spinal column. He can name the gene, and
        > > seems to say it causes all the same changes in a mouse. I don't
        > think he means the mouse became bipedal, but he only gives it a
        > sentence so I may have misunderstood.
        > >
        > > 3. He says this random change in the body plan could happen to the
        > genome in a second, and "impose itself"on the species.
        > > It could impose itself on the chromosome of an individual
        > organism but it could not guarantee that the embryo would survive and
        > the resulting organism would outcompete its contemporaries in the kind
        > of environment it inhabited. He gives no indication of what that
        > habitat was.Without that we cannot judge the chances of its surviving
        > for even a generation.
        > >
        > > 4. This was the beginning of bipedalism, the great advance that is
        > said to have freed our hands and made us the top species. Yet all the
        > apes but one opted out, one after another. If it was so adaptive, why
        > did they do that? If that modified vertebra made it so uncomfortable,
        > how can the chimp and gorilla walk on four limbs today without visible
        > discomfort?
        > >
        > > 5. I can take his word for it that Moro may have walked erect,
        > and that we may do so because we are its direct descendant. I agree
        > that it is unlikely that we went through a period of knuckle-walking.
        > I find it much harder to believe that all the other apes went through
        > a period of upright walking on the ground and all defected on it one
        > after another.
        > >
        > > 6. He seems to envisage that after the hylobates defected, the
        > orang's ancestors were still bipedal, and after the Asian ones had all
        > returned to the trees the gorilla's ancestor was still bipedal, and
        > after the gorilla took to knuckle-walking the chimp's ancestor was
        > still bipedal. That still gives me not the ghost of an answer to the
        > question that originally brought me into the study of hum. evol. -
        > namely, why are we so different from the chimpanzee? And in so many
        > ways? and if we found an answer to all the other ways, might not that
        > throw light on the difference in gait? He never casts a glance at any
        > other trait besides the lumbar change. I grant that others may have
        > underestimated its significance but it is going a bit far to present
        > it as the holy grail when the other apes didn't find it worth hanging
        > on to and had not the slightest difficulty in scrubbing around it.
        > >
        > > 7. He is very clear and logical right up to the last section where
        > he begins to speculate on why the other African apes reverted. He
        > makes one good point "Quadrupedalism is a first- class way of getting
        > around- " an excellent reason why the "imposition" of bipedalism by a
        > random mutation would have been unlikely to stick in the first place,
        > without some environmental pressure in its favour. . . He makes some
        > unconvincing ones, e.g. that the other apes were threatened by our own
        > ancestors who were more efficiently bipedal. Why was that if they
        > shared a common bipedal ancestor? Did we get more efficient or did
        > they get less efficient, and why? Above all he uses a significant
        > phrase. Because they felt threatened they "went back into the forest."
        > Back from where?? He doesn't specify but he doesn't need to.
        > >
        > > 8. He uses at one point the phrase "this was the how " of the
        > change to upright walking. He is great on the how. But he is not so
        > good on any of the whys.
        > >
        > > Elaine
        > >
        > >
        > >
        > >
        > >
        > > __
        > >
        > > [Non-text portions of this message have been removed]
        > >
        >
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