Re: Is the AAH a legitimate hypothesis? Of course it is.
From: Algis Kuliukas (algis_at_RiverApes.com)
Date: 01/21/05
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Date: 21 Jan 2005 05:50:23 -0800
Rich Travsky wrote:
> Algis Kuliukas wrote:
> > Of course not but if it's a choice between drinking from a fresh
water
> > river or digging down in a metre of earth to suck mud, I know which
I'd
> > choose.
>
> Your choice is irrelevant. *You* have no role in this, early hominids
> do and you make yet another mistake in assuming they'd have the same
> likes and dislikes that you would. A river may not be available; go
> back and re-read how the savanna chimps deal with it.
A river might not be available, true. And in such situations being
smart enough to be able to come up with an alternative life saver is
clearly an advantage, I can agree. But I still doubt that this is
enough of behavioural foundation for genes that design bodies that
waste water to thrive on. Those genes are, however, likely to prosper
where fresh water *is* easily available most of the time.
[..]
> > No. Why do you have to always deliberately misrepresent what I'm
> > saying? I didn't say wait around an hour THEN throw rocks, I was
> > suggesting that it might take an hour of careful rock throwing to
move
> > the crocs away.
>
> That's not the way your statement reads to me and your "explanation"
is
> no improvement. An HOUR of throwing rocks???? Wow, that's a LOT of
rocks.
> How many per minute you think it would take? What size? Where did
those
> rocks come from? Weere they already there, or did they carry them
over?
> Is this a part of Archimede's throwing "theory"? You know, that many
> rocks kinda negates that flat waterside bipedal environment you're
often
> refering to...
Why is rock throwing suddenly such a fantastic concept? Oh, yeah. I
forgot. I'm postulating they might have been used against crocs. If I
was thinking that they might have been used to throw at hyenas, that
would have been perfectly fine. Odd that.
Rich, you find more rocks near river banks than you do out on the
savannah.
> > If there were terrestrial predators around then that would,
clearly, be
> > a different problem. They'd have to climb trees or, maybe, go into
the
> > water to escape them. If both crocs and terrestrial predators were
> > present, then that would be really tough.
>
> Another sig is born.
Why's that? Do you think it's funny? Not true? Are you disputing it?
> > Are you suggesting they'd be any safer out on the open savannah?
>
> Water sources draw and thus concentrate predators. Savanna chimps
seem to
> do ok, tho...
So the best strategy to have evolved would have been to leave the
water's edge and go and look for some tubers to dig up in the mid-day
sun, right? Is that your view?
[..]
> > > Not an extreme position. It's a very real set of dangers that
other
> > > animals are also aware of.
> >
> > Yes but we're a bit smarter than most other animals, aren't we? We
> > clearly overcame those problems.
>
> Kinda like finding other sources of water, eh?
So, if we postulate being smart helped hominins find drops of muddy
water dug from the ground in the sun-parched, open grasslands of
Pleistocene E Africa (during a dry phase, not a wet one, note) - that's
fine, that's good science, that. But if we postulate that being smart
might have also helped them cope with predators around in and around
precious water courses and in fact take advantage of that richness in
fauna and even go swimming there sometimes - that's just crazy, it's
not science at all and must be ridiculed.
Can't you see how this sounds a bit obsessive? What *is* your problem
that humans evolved in part by taking full advantage of waterside
resources?
[..]
> > > Again you think the only water sources are large bodies of water.
> >
> > No I'm not. But they're clearly by far the safest bet.
>
> Actually, you are. How many times have you even mentioned other
> sources of water?
I did earlier in this posting and several times before. I have accepted
that sweat cooling makes sense as an adapation for being temporarily
*away* from the water's edge. I've shown a far greater willingness to
accept some of the savannah-based arguments than you who, typically for
an aquasceptic, cannot bring yourself to concede it influenced our
phenotype in any way whatsoever. My point is that it's neither one nor
the other, it's both. Humans were never aquatic - that's ridiculous.
But it's equally ridiculous to think we were pure savanna dwellers
either. What is not ridiculous is the notion that it was the
juxtaposition of the two - ie at the water's edge, that best explains
the way we are.
[..]
> > You take her [Pond's] conclusion (her interpretation) but ignore
the facts
> > she's
> > using to base that interpretation on. All I'm arguing is that Pond
says
> > humans are fatter than primates. You're claiming that her
explanation
> > of that, through sexual selection, answers the problem. it doesn't.
>
> Why not?
1. There's not sufficient sexual dimorphism.
2. It does not explain why human infants are so fat.
> > > > But Pond's clearly reporting that humans are fatter than apes.
The
> > > > question is: Why? You don't even want to accept it's a valid
> > question.
> > >
> > > How many primitive cultures throw their babies into the water?
> >
> > Zero. What has this got to do with anything? Misrepresenting my
> > argument again?
>
> Then baby fat has nothing to do with the water.
Oh that's really logical. So if no human cultures "throw their babies
into the water" then baby fat has nothing to do with the water. Ever
heard of accidents?
> > No I'm not accepting it. It makes most sense in that setting. How
many
> > savannah dwellers are fat, Rich?
>
> Steoptygia anyone? Food supplies can be seasonal. Makes sense to pack
it on
> when you can. See bottom of the post about zoo animals...
But Pond's study took captivity into account. Why do human infants get
so much fatter than chimp infants if it's to do with 'packing it in
while you can'?
> > > > > [...]
> > > Our ancestors wandered all over Africa (australopiths ranged from
> > South
> > > Africa to Chad - and not by swimming), Asia, and later Europe.
Food
> > was
> > > not always to be at hand. The ability to store energy in the form
of
> > > fat is a decided advantage.
> >
> > So food was only a problem for Homo sapiens, and no other savanna
> > animal?
>
> I said australopiths, not homo. And what do other animals have to do
with
> that?
The human propensity to put on fat exceeds other apes, primates and
terrestrial mammals. That was what Pond found. The question is: why us?
We don't know how fat a'piths were.
> > > > What about human infants? They're not fat because of exposure
to
> > > > over-eating. They're *born* fat. Why should that be?
> > >
> > > Because fat is stored energy to help the baby survive - not to
swim.
> >
> > Why's that, Rich? How long would a baby survive without it's
mother, no
> > matter how fat it was? Why do no other primate infants need this
stored
> > energy? It's just special pleading again.
>
> If food supplies are lean, then the mother will not be able to
reliably nourish
> the baby - guess what, fat is stored energy... no special pleading
again.
But without mum, baby dies... rather quickly. So what is the
evolutionary sense in transferring a large storage of fat into the
baby? Why not leave it mum until the baby feeds using it, like
practically every other mammal (except aquatics of course) on the
planet?
[..]
> > > You must learn to read more carefully. I illustrated that
aquaticness
> > > had no role in it. Show where I denied that humans can't get fat
->
> >
> > You were arguing that our fat was a phenomenon of overeating not a
> > human universal. Now, good, you seem to accept it *is* a human
> > universal. Progress.
>
> Not a universal? WHERE did I say that???? Show EXACT quote:
>
> Learn to read more carefully:
>
> I illustrated that aquaticness had no role in it
>
> I can see you're not only NOT making progress, you're losing ground.
I
> showed that acquiring fat depends on such things as availability and
> quality of food.
Then you have to explain why humans specifically need to put it on more
than other apes, primates and other terrestrial mammals. If it's a
human universal to put on fat (agreed?) why is it even a characaterist
that we are discussing?
[..]
> > > And how many chimps hands have you actually examined?
> >
> > Only in photos and in zoos. I think it's a pretty obvious, if very
> > minor, point.
>
> Obvious what? That it has nothing to do with aquaticness again
because
> too much muscle and skin would work against the grip? Agreed.
I think you're geting confused. Ape hands, I'm arguing, do have nothing
to do with aquaticness - that's why I'm suggesting that they have tough
hands with little or no skin in between the digits, compared to ours.
[..]
> > > > [...]
> > > > ... but they still can't swim as will as we do!
> > >
> > > Irrelevant. Let's see a chimp do a marathon.
> >
> > Absolutely relevant. I accept that humans are better at endurance
> > running than chimps and guess what, I think it's the result of
> > selection. Do you? Or do you think it's just because we're smarter
than
>
> Why would endurance have ANYTHING to do with smartness?????
Good, so you agree it's an adaptive trait?
So, human advantage over chimps at endurance running is down to natural
selection.
Chimp advantage over humans at climbing trees is down to natural
selection.
.. repeat for billions of other animal pair-substrate combos...
But human advantage over chimps at swimming must be anything else *but*
selection.
Can't you see how your determination to deny any kind of role in our
evolution looks increasingly ad hoc?
> > they are? We're better on land than they are, they're better in
trees
> > than we are - both due to natural selection. Why is it that our
clear
> > advantage over them in water is not similarly explained?
>
> We can dance and do gymnastics too - a whole range of body motions
> chimps can't do. Could it be we generalists?
Generalists are more aquatic than arborealists. Or are you arguing that
humans were specifically non-arboreal, non-aquatic generalists (code
for savannah dwelling specialists?)
[..]
> > > What you miss is that our body build lets us do all those
activities
> > -
> > > hence, there's nothing special about swimming.
> >
> > Special pleading.
>
> Only on your part. How do you explain why we can all those things
with the
> same body?
Because we're generalists. See, I accept we're generalists. But in
accepting that, I agree to understand it's full implications. For me, a
generalist *means* a generalist. It can climb, but not as well as an
arborealist. It can run, but not as well as a savannah dweller. It can
swim, but not as well as an aquatic animal. Get it? No, I don't suppose
you do. You will have to drive out that last part of the definiton at
all costs, won't you - because we just can't have any bloody dreaded
'a' factor involved. Bizarre.
> And while you're at it explain why swimming is not a MAJOR
> means of getting around for us? Unless you want dredge up Marc's
nonsense
> about herds of hominids floating around from island to island
breathing
> through their snorkel noses....
'is'? 'MAJOR'? THe AAH, as I understand it, is saying that our
ancestors *were* more aquatic in the past than we are today (exactly as
Hardy asked 65 years ago) and than ape ancestors were.
Sorry to disappoint you but I'm not proposing an aquatic ape. I would
have thought you might have understood this by know.
[..]
> > No it's not. If it were sexual selection you'd get some clear
sexual
> > dimorphism, as with proboscis monkeys. In human you don't. Special
> > pleading.
>
> Sexual selection does not have to result in dimorphism. AA special
> pleading to insist it would. Neoteny - recall the chimp embryo link?
It usually does. It's most parsimonious that dimorphic traits are the
one most likely to have evolved through sexual selection.
[..]
> > I'm looking at images of He (Bodo, Sangiran 4, Sangiran 17 and
> > Zoukoudian) and Arch Hs (Broken Hill 1) - all have degrees of
sagittal
> > keels. Mark Collard introduced us to the idea at UCL, although, of
> > course, he didn't offer an aquatic explanation for them. I suspect
> > again, if an aquasceptic says that He had sagittal keels, though,
> > suddenly you'll have no problem with accepting the idea.
>
> Sangiran 17 - no keel.
>
>
http://www.msu.edu/~heslipst/contents/ANP440/images/Sangiran_17_front.jpg
>
> http://www.science.mcmaster.ca/geo/research/age/skull.htm
>
> Solo 6 - no keel
>
>
http://www.msu.edu/~heslipst/contents/ANP440/images/Solo_6_langle.jpg
>
> Bodo - what keel?
>
> http://www.hofesh.org.il/articles/science/erectus-15-bodo-skull.jpg
>
> Zhoukoudian - all but *gone*
>
>
http://www.msu.edu/~heslipst/contents/ANP440/images/Weidenreich_front.jpg
>
>
http://www.msu.edu/~heslipst/contents/ANP440/images/Zhoukoudian_XII_front.jpg
>
>
> Ergaster - no keel
>
>
http://www.msu.edu/~heslipst/contents/ANP440/images/KNM_ER_3733_front.jpg
>
> ETCETERA
>
> Collard didn't offer an aquatic "explanation" because he knows the
keel is an
> anchor point for jaw muscles - nothing more - and that the "keel"
just
> resembles the structure on a ship but NOT the function.
Hah! Congratulations on finding so many images in which the actual
trait being contested (the sagittal keel) is obscured by either being
dark, in side profile or by using the wrong image.
So, are you accepting that He had a sagittal keel now, or not? Yes or
no? Collard taught us that they did. Which option are you going to go
for? Tough isn't it.
[..]
> > Have you ever swam with your eyes open looking ahead of you in the
> > water? Your nose is at the front.
>
> I don't know how to swim. Not that it matters - you just took first
> prize for special pleading. What's BEHIND the nose? A flat face. Bow
> effect lost.
It's not lost. The point of the bow is to cause the water to flow in a
relatively smooth, rather than a turbulent, way. Having a big hood-like
nose with downward pointing nostrils, like we have, rather than a flat
structureless nose with two rather gaping forward-pointing nostrils,
like chimps have, is bound to be advantageous whilst swimming. Again if
you can't even accept such an obvious point it's difficult to see how
one could reason with you.
[..]
> > > > > You're missing the point. You want the hair line to be the
result
> > of
> > > > us
> > > > > looking down in the water (lord knows how many hours a day
THAT
> > would
> > >
> > > How many hours a day????
> >
> > I don't know. *Some*. More than chimps did.
>
> Not "some" - A LOT. Completely unsupportable. Quit using it unless
> you can work it out. (there goes another one)
'Some' is not unsupportable. It's rather obvious. Humans swim more than
chimps today. More humans drown than do chimps - there's selection for
you every day. The evidence of human migrations and shell middens
indicates we did more swimming than they did for the last 160Ky. And
the evidence from He suggests that Homo has been doing so for at least
2My. And yet you call it unsupportable and claim that I'm not being
scientific.
> > As it must causes some extra drag in water then there clearly is
some
> > cost.
>
> Again - HOW MUCH TIME IN THE WATER for this to be the remotest
> of factors????????
*SOME*
About as much as having a slightly bigger brain might translate into
being slightly more intelligent and how that slightly greater
intelligence might translate into slightly greater selective fitness.
Or, about as much as having slightly paler skin might help humans
living in slightly higher latitudes to survive with slightly less
sunshine and make do with slightly less Vit-D.
The factor can be very slight without the resulting selection being so.
> > > You appeal to sexual selection here and just above claim "costly
> > > signalling" against it...
> >
> > Costly signally is an argument for sexual selection, Richard, not
> > against it.
>
> Then make up your mind.
I'm the one arguing beards are for sexual selection. There's a clear
sexual dimorphism. Noses aren't because there's little sexual
dimorphism.
[..]
> > > Reduction of hair and sweat cooling go together. Surface area and
> > exposure.
> > > The hairline exposures the face for social reasons - reading and
> > showing
> > > emotion. Since we live on land, and are social creatures, which
is
> > more
> > > likely as a reason?
> >
> > This is a false dichotomy. It's not that *either* we swam *or* we
were
> > social creatures. Clearly, we did swim, we do swim, we were social
> > creatures and we *are* social creatures. Both.
>
> So how much TIME IN THE WATER for this to be even significant???? And
then
> compare that with the amount of time spent in social interactions.
Care
> to predict the VERY lopsided ratio to come out that??? (there goes
another
> one)
Not much, but *more* than chimps. Selection works on the tiniest
variability. I would have thought you'd have known that. Again, I'm not
saying that eyebrows were *not* a feature that helped in social
interactions. Traits can have more than one purpose, Rich. Natural
selection tends to optimise their recruitment to more than one role,
hadn't you noticed?
> > > > One of my fellow students at UCL (an aquasceptic, of course, I
> > might
> > > > add!) told me the story. Her 'mates' shaved her eyebrows off
once
> > for a
> > > > stunt and it affected her swimming and her experiences of
taking a
> > > > shower.
> > >
> > > Wow. One whole data point.
> >
> > Yes, One-nil.
>
> No, one against 5 or 6 billion-plus for social interaction...
It's a false comparison. Is this the best you can do? One argument
*for* eyebrows being beneficial in and around water. Zero for it *not*
being.
> > Well swimming is a form of locomotion and my argument, you might
have
> > noticed, is that mouth breathing is best explained as a swimming
> > adaptation.
>
> Huh? Quick experiment. I just took a few open mouthed breaths while
sitting
> at my keyboard. Hmmm. No water around. How much time in the water
would
> be needed to produce this hmmm?
Look, the point is that in water you *need* to inhale a lot of air in
quick, deep breaths. Sitting at the computer, you don't. Get it?
> > As for the swimming primates, it's a good objection. I'd want to
some
> > evidence showing how long they'd swam compared to sister taxa that
> > didn't and some comparative data on the position of the larynx in
those
> > species compared to sister taxa that do not swim. If they've been
> > swimming for a significant period of time and there's no difference
in
> > the larynx then you can take this as evidence against the
'Descended
> > Larynx for Mouth Breathing whilst Swimming Hypothesis.'
>
> How long? Allen's swamp monkey - long enough and constant enough to
actually
> have an adaptation to show for it:
>
> http://members.tripod.com/uakari/allenopithecus_nigroviridis.html
> ...
> Between the fingers and the toes there is webbing to assist in
swimming
> (Rowe, 1996).
> ...
>
> This is material you should have come across LONG before now.
You're right. Thanks.
[..]
> > > > Well, it would be a prediction of the 'speech though
> > swimming-induced
> > > > fine breathing-control' hypothesis that any regularly swimming
> > primte
> > > > should exhibit finer breathing control than sister taxa that
had no
> > > > such aquatic exposure. I'm not sure how one might test it
though.
> > >
> > > So you can't claim it as part of the AA argument. There goes
another
> > one...
> >
> > No it doesn't. Until the data arises as argued above, it's still
open.
>
> "speech though swimming-induced fine breathing-control" - when
> proboscis, allenopithecus, macacas, talapoins, whatever, start to
> show vocal language skills like humans, let us know.
No, when we see that the position of the larynx in those taxa are not
signifcantly different from sister taxa that do not swim. That was my
point. I think you knew that though.
[..]
> > > > > My dog can swim and wade. My dog is aquatic! Two out of
three!
> > > >
> > > > If most breeds of dog were poor in water whilst yours was a
good
> > > > swimmer wouldn't it be reasonable to conclude that the
difference
> > was
> > >
> > > Didn't say he was good - and I meant my former now dearly
departed
> > dog.
> > >
> > > > due to some kind of selective breeding? Or would you just argue
-
> > hey,
> > > > my dog can do lots of things, it can't be due to selective
> > breeding,
> > > > it's just a smart dog.
> > >
> > > Most mammals (if not most animals) can swim if they need to.
> >
> > You didn't answer the question.
>
> I did. Since most animals can swim if needed, neither smartness nor
> selective breeding must be a factor.
Let me try it again:
'If most breeds of dog were poor in water whilst yours was a good
swimmer wouldn't it be reasonable to conclude that the difference was
due to some kind of selective breeding? Or would you just argue - hey,
my dog can do lots of things, it can't be due to selective breeding,
it's just a smart dog?'
See? I'm trying to get you to answer the question that if your breed of
dog swam better than other breeds wouldn't you think there'd been some
selective breeding that had gone on? Or would you just assume that the
dog was smart, flexible, or cite whatever else it could do as well as
an *excuse* to explain why it could swim better?
[..]
> > As I said, if there is data that they've regularly swam for an
> > evolutionary timescale (e.g. 5my) and sister taxa have not and
there's
> > no difference in their phenotypes then this would be good evidence
> > against the AAH.
>
> See above re allenopithecus.
Thanks for the PRO AAH evidence. As I said, if there was "no difference
in their phenotypes then this would be good evidence against the AAH."
But, as you have so kindly pointed out, there *are* differences, just
like humans have more webbing than chimps.
> > Delusional. We're naked and fat to name but two. How many savannah
> > animals are like that?
>
> When did nakedness and fat become solely aquatic traits? How much
> hair do elephants have? Or rhinos? How many fat humans in savanna
> lifestyles? Would't a gazelle get fat if it had access to lots of
food
> and didn't get to exercise? Say, diet management in zoos! Check this
> out (scroll down):
Let me try again. Who is saying fat is "soley" an aquatic trait? I'm
saying it has several uses but that all thing being equal it helps in
an aquatic environment more than it does in dry open grasslands.
Humans, you may have noticed, are not as big as elephants and rhinos.
I thought you'd conceded that human adipocity is a universal trait in
the 'needs-to-be-explained' category. When Pond argues it's for sexual
selection, you have no problem accepting that our fat is unusual, when
the explanation is slightly aquatic you dispute there is anything to
explain. A bit selective aren't you?
Make your mind up.
Q1: Is human (specifically) adipocity something that needs to be
explained, or not?
Q2: If yes, why are we so different? (seperate question.)
[snip, zoo animals get fat - we know]
> >
> > 1. Allen Swamp Monkeys are 11x (male) - 14x (female) smaller than
> > humans, therefore body hair, rather than fat, acts as a significant
> > buoyancy aid. Proboscis monkeys are 3.3x (male) - 5.5x (female)
smaller
>
> This does not look like a buoyancy aid:
>
> http://members.tripod.com/uakari/allenopithecus_nigroviridis.html
That's an interesting conclsion considering not one image shows them
swimming.
Small mammals (and Allen monkey are small) tend to use air trapped
under the fur as buoyancy aids. Are you disputing that too now? Or, is
it ok for mammals to use air trapped under the body fur for buoyancy,
as long as they're not primates?
> > than humans. This effect is not so great but, I suspect, it's still
> > sufficient to select body hair for buoyancy rather than fat. Their
>
> So when did our ancestors "get fat"? 2mya? 4mya? When?
I don't know. I suspect it was late, around the Hs speciation event or
perhaps before, at the He speciation.
> > smaller size also vastly reduces the depths of water at which
bipedal
> > wading is a better option than swimming.
>
> So? It's a relative thing.
Well yes, of course. If you are an allen monkey, the depths of water
you could, even theoretically, wade bipedally through would be less
than about 30cm in depth. Humans can wade bipedally in 5x those depths.
The bigger you are the more places bipedal wading is an option. If you
inhabit the water's *edge* these are the kind of depths of water where
being a little bigger is going to make far more resources accessible to
you.
> > 2. Both these primates live in densely wooded habitats, whereas
humans
> > probably have not done so for for about 2Ma. This (guarding against
> > abrasion) also acts as a major factor to retain body hair. I
suspect
>
> It's major? Chimps and gorillas live in "densely wooded habitats" and
their
> hair is much reduced in comparision. And those swellings on chimp
females!
Size factors have to be considered too, of course.
Algis Kuliukas
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