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On Sat, 20 Dec 2008 01:08:28 -0700, RichTravsky <...@hotmMOVEail.com
Edible vegetation. Fruit, for example.
The only problem: getting them into the water.
So don't go in the water.
No other resorts to something easily avoided like "don't go in the water".
Define "occasional, intermitent [sic] wading". Once a day for 10 seconds?
What?
What fear? There are already numerous contexts for bipedal behavior, this
woould be one more.
The probability of a chimp being stupid enough to go into deep water...
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On Sat, 20 Dec 2008 02:08:39 -0800 (PST), Algis Kuliukas <...@kuliukas.com
On Dec 20, 5:08 pm, RichTravsky <...@hotmMOVEail.com
How exactly does this make them bipedal?
Duh. Flooded gallery forests. Gallery forests... litle canopy.
Flooded... water. Which part of this don't you understand?
You're a genius, Rich. I never thought of that. Yes, right, they would
just sit in their tree and starve to death.
Enough. Enough to get down from one clump of trees and wade across to
another. Perhaps enough to feed from low branches. It will vary, of
course. Is this too difficult for you/
How many post grad students have ever been encouraged to study
anything that even vaguely relates moving through water to human
evolution? If you can cite one, I'd love to hear about it. I suspect
the answer is ZERO.
It's a probability that is higher than Rich Travsky being clever
enough to realise that in flooded gallery forests hominids would often
not have the choice.
Crikey. Is the the level of "debate" on sap these days!? "they
wouldn't go in the water". Blimey.
Algis Kuliukas
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On Sat, 20 Dec 2008 01:58:26 -0800 (PST), rmacfarl <...@alphalink.com.au
On Dec 20, 4:11 pm, Algis Kuliukas <...@kuliukas.com
May I suggest you read through right to the end of my response before
you respond to any individual point.
That last part is non sequitur (at least, I can't follow it). What
difference would it make if we did have evidence of Pan ancestors
living elsewhere?
Also, when you say "Mainstream paleoanthropology has often placed
early hominids in gallery forest habitats", do you mean merely that
this has been a common speculation, or are your specifically thinking
of primary research, say of taphonomic data related to hominid fossil
finds? (Serious question...)
Yes, absolutely that's the critical question. Note, though, that
you're already having to make some assumptions, and you're about to
make a whole series more. Change an assumption and your whole scenario
- any scenario - needs to be reconsidered. And this has to be based on
data. Importantly, the strength of the whole scenario will depend on
the degree to which each assumption is supported by the available
data.
OK. That doesn't rule Kingdon's scenario out, but it does give reason
to consider other scenarios.
I note that there is of course one primate species which is well
adapted to more open habitats, which is an obligate biped.
"Far better" is your subjective assessment, & "evidence-based" - well,
let's reserve judgement on that too.
Talk about begging the question!
Parse this:
"Not wading in waist deep water obviates the need for an ape to move
bipedally with any predictability."
Algis, this is just what we've been trying to get you to see. If the
apes don't go into waist deep water, this clear, simple, immediate
selection pressure is immediately, clearly and simply no longer there.
Don't you see? What you've postulated isn't evidence. It is you
leading the evidence with your conclusion, because you're so sure they
had to have gone in the water.
[Brace yourself...] What if they didn't?
Bollocks, again! Hominids "would have no choice other to wade through
water for several weeks a year"? Of course they would have had
choices. What about migration, just for the sake of argument? Can you
think of any reason why hominids could not have practiced seasonal
migration, or some type of nomadism, in response to environmental
changes such as flooding, seasonal fruiting, etc? Maybe they just
moved to another part of their home range where the floods didn't
reach, like, say, up the hill? Maybe the trees were closer together
than you thought. Maybe they *swam*. Maybe anything you bloody like.
Although plausible, nothing in your speculative scenario thus far
counts as evidence, so your claim that it is "far better" and
"evidence-based" fails.
Paragraphs like that one are the objective evidence I was talking
about which demonstrate your inability to be objective in respect of
the so-called "aquatic ape hypothesis".
Possibly, and the data would be useful.
However, and you need to get your head around this fact, none of the
variables you describe, individually or taken together, could be used
to prove the hypothesis that hominid bipedality evolved from wading in
a gallery forest.
I suspect that a good supervisor would also suggest that you need to
consider more strongly the null hypothesis that hominid bipedality
*did not* evolve from wading in a gallery forest.
You might even reach the conclusion that in the current state of
available knowledge, you can't prove or disprove either hypothesis. If
you did, you might find that conclusion salutory...
Ross Macfarlane
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On Sat, 20 Dec 2008 03:40:08 -0800 (PST), Algis Kuliukas <...@kuliukas.com
On Dec 20, 6:58 pm, rmacfarl <...@alphalink.com.au
I put it in just for you, Ross. You denied my claim that hominids
lived in gallery forests more than Pan because there is no evidence
for Pan. Fair point. But here I'm saying that mainstream anthropology
have done the same despite the same anomaly. They ignored it, so I
will too.
Kingdon's book has scores of references. I'll dig them up for you if
you want but it would be a waste of time,
Just sounds like waffle to me.
Yes, but how did it get there?
Well, it actually compels an ape to be bipedal and it would kill them
if they were quadrupedal. I think that's better.
I know you like to try to play clever word games but do you deny my
statment or not? I think you're full of bullshit.
In flooded gallery forests they'd have had no choice.
Of course I have thought of that. Have you thought about what if they
did?
Well yes. How about the risk of predation on the open plains?
Australopithecines were clearly at least partly adapted to climbing so
that evidence indicates that they'd have stayed closer to the trees. I
do not preclude the idea that they could have migrated to a completely
different place but you shouldn't preclude the idea that they would
have stayed within the gallery forest habitat that was their base.
Perhaps they did a bit of both. My point is that gallery forests
increase the amount of wading needed and the more wading an ape does
the more bipedal it gets.
Yes, maybe. And maybe they waded.
It's odd. You seem to find the idea of wading through water so
repellant you'd rather have them migrating for miles across open
plains to find another gallery forest rather than face the possibility
that it might have been a regular part of their repertoire. Here,
you'd even rather have them swimming. (Of course elsewhere you'd again
rather have them wading - anythting to deny that Hardy/Morgan might
have been right all along.)
And what, exactly, is the evidence for them not wading in those
gallery forests?
Well how many post-grads have been encouraged to look at ideas such as
this? My guess is zero, what's your's? Out of thousands of such
research projects it's overwhelming, objective, evidence that I'm
right.
Nothing could prove it, nothing could prove otherwise. We're talking
about probabilities here. What's more likely?
It's a question of likelihood. As E Africa shrank and forests shrank
closer to permanent water courses, are our ancestors likely to have
stayed in the shrinking forests?
Would these gallery forests have been subject to seasonal flooding?
Would they have had a limited canopy, requiring hominids to get down
from the trees? Would hominids have been more likely to stay local
duuring these seasons rather than migrate to other more distant
habitats? During these flood periods would they have had to wade
regularly? Would there have been selection for better wading?
I think the likely answer to all those questions is "yes".
Algis Kuliukas
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On Sat, 20 Dec 2008 05:45:40 -0800 (PST), rmacfarl <...@alphalink.com.au
On Dec 20, 10:40 pm, Algis Kuliukas <...@kuliukas.com
[sigh] I didn't deny your claim that "hominids lived in gallery
forests more than Pan". I denied your claim that "humans evolved in
waterside habitats more than chimps", on the basis that we don't know
where Pan evolved. (For all we know, pre-Pan fossils could yet be
found in gallery forests.)
It would, because I won't read them (Lee probably would.)
I'll take it as read that your claim is based on primary research
data, always understanding that conclusions are subject to later
reconsideration based on new data or new interpretations of the
existing evidence. (I could be a lawyer at this rate...)
Then read it again! If you're a serious scientist, you should find
nothing in it to disagree with.
Not the point. How did patas & baboons get there? You want to cite
them as negative evidence, then you have to concede Homo as evidence
the other way.
I sometimes think you're an ignoramus, but mostly I'm too polite to
say so.
You can claim that an ape in waist-deep water has to stand up to avoid
drowning. You can't claim that an ape in a flooded forest has to stand
in waist-deep water.
Since you apparently couldn't parse my sentence, what it was saying
was that if you don't put the ape in waist-deep water, you can no
longer predict that they will go bipedal.
That's the keystone to your whole scenario. Your assumption is that
they'll have to wade in waist-deep water, but if you don't assume that
they have to do that, the whole thing collapses. Now I can see you've
convinced yourself that it must have happened that way, but
objectively, that conclusion is false. Even if you do put the hominids
in forests that flood seasonally, they don't have to wade waist deep.
There are other serious flaws in what you're proposing, but that's the
killer, and you haven't got the evidence to make it more than a
harmless speculation.
Of course they'd have had a choice. Forests aren't flat, flood depths
aren't uniform, trees aren't always close together, and smart animals
know that floods usually start after heavy rain.
As I asked in the other thread: make a list of the things you'd do if
your house was flooded, & let me know if one of them was "move to
higher ground".
I have already described that idea as "plausible". Can you,
objectively, deny that my alternatives are "plausible" too? (You may
wish to say they aren't equally plausible, but you'd have no objective
basis for that conclusion.)
a) Who the Hell said *anything* about open plains?
b) I cannot but point out that even the open plains usually have
trees.
Please try to stay away from the "treeless savannah" straw man.
Correct on both points. Now you're making progress.
That's 2 points, & both are speculative (i.e. there's no evidence
backing them up). You have imagined a scenario where flooded gallery
forests *may* have increased the need to wade. Wading, depending on
the conditions, *may* increase the frequency of bipedalism. And
there's a third, underlying assumption that such bipedalism would have
led to selection in the direction of obligate bipedality - but this
claim also is speculative, and there is no cause to believe that such
selection must have occurred.
I'll take it as acceptance of my point, that your scenario is not
evidence-based.
No, it's not odd, that's just you projecting again. I have not
dismissed the wading hypothesis out of hand, but you really seem to
have a problem with contemplating other alternatives (which is a
necessary condition for being a scientist, I humbly submit.)
"Migrating for miles across open plains" is your straw man. Remember
that one? That's one of those logical fallacies where you construct a
caricature of your opponent's argument in order to misrepresent it and
render it unacceptable. *Nowhere* did I say anything at all about
going miles across open plains. So pull your head in and rethink your
critique.
I would also point out that living in a swamp isn't generally
considered the healthiest place for a primate to reside. I don't know
about you, but if my home gets flooded & the option exists to move up
the hill, or somewhere nearby that was dry & had access to food water
& shelter, I'm probably going to take it.
Oh, no, no, no, you don't get to play that card. The null hypothesis
is that they weren't wading. If you've got no evidence to say they
were, then your scenario is not "evidence-based" and it can by no
measure be claimed to be "far better" than any other scenario.
That doesn't make it any worse than any other speculative scenario
though, I'll give you that, but that isn't much.
My guess is as good as yours, and the explanatory value of your guess
is in this case equal to its assigned empirical value. (In other
words, since you often can't follow my ironic wordplay, I'm saying
your guess is worthless.)
For Heaven's sake Algis, stop making these meaningless tilts at this
mythical paleoanthropological windmill. What purpose does it serve? It
can't be good for your state of mind. No one else cares, and it just
gives me the shits...
Your guess is as good as mine - which is not very. But again, I take
that as validation of my point that your scenario is not evidence-
based.
Yes well, you would think that, wouldn't you.
[Still trying...]
Ross Macfarlane
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On Mon, 22 Dec 2008 16:41:56 -0800 (PST), Algis Kuliukas <...@kuliukas.com
On Dec 20, 10:45 pm, rmacfarl <...@alphalink.com.au
If one assumes that these hominids were on the lineage leading to us
(as I am here) then there's no distinction.
So you should concede the point. I know you won't though because
"admitting you're wrong" is not part of your repertoire.
Nah.. just waffle.
I can because as there's not a continuous canopy gallery forest
hominids would have to get down from the trees.
But I did. Your waffle tried to obfuscate the simple fact that in
gallery forests there is no continuous canopy and therefore a need to
get down from the trees but anyone can see through that.
Yes they do. So your whole counter-argument collapses.
What other serious flaws?
At the very least, the wading factor compells more bipedalism in
hominids than if there were no wading factor. How can this be a bad
thing when we want to explain our bipedality? Why on earth would
anyone resist it? Oh yeah, I almost forgot - because it would require
some bigotted people to have to admit they'd been wrong for a long
time and we can't have that. A really great appraoch to science, isn't
it?
Yes but are you telling me that wadin through shallow water WOULDN'T
be one of them? That is the material point. You avoid it like the
plague. In seasonally flooded gallery forests hominids would be
compelled to move bipedally more than in open savannah habitats or
tropical rainforest habitats.
It's this binary thinking again: Either they waded or they did
something else. it's not like that. The point is that they would have
done something else if they could, I accept, but sometimes they would
have had no choice. Placing them in seasonally flooded gallery forests
increases the likelihood of wading, that's all. More wading = more
bipedalism. Wading therefore is HELPFUL when explaining the evolution
of homnin bipedalism.
You're the one who keeps asking when did humans become savannah
adapted?
So, the point is gallery forests increase the probability of wading
and, as more wading means more bipedalism, it increases the
probability of bipedalism.
Tell me what evidence there is for any model of bipedal origins? Start
with your favourite and work down the list from there. The wading
hypothesis has better evidence than any of them.
Sure, there are assumptions and speculations. Name one model of
hominid bipedalism where there are no assumptions and speculations.
You can't because there aren't. More double standards.
It's more evidence based than most of the other models. No model is
more evidence based than the wading model. If you disagree name me
one.
I do not have a problem contemplating other models. You are the one
who has a problem contemplating wading.
Compared the straw men in your head, it's nothing.
See? Who said "swamp"? You did. I said "seasonally flooded gallery
forest" - when it comes to the main scenario for human-chimp
divergence at least.
Then name one other model that is more evidence based.
It has more evidence from extant apes, better evidence from
paleohabtats and better evidence from energy-efficiemcy studies.
It shows that no science has been done - hence the ignorance. It shows
a total unwillingness to even study the thing. No wonder so many
people are so biased.
It's AS evidence based as some, MORE evidence based than most. None is
more evidence based than it
You haven't contradicted one of them. You're whole argument has been
to make the claim that I'm going for exclusivity, when I'm not. More
wading is enough. It's a point you have evaded.
Algis Kuliukas
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On Wed, 24 Dec 2008 15:25:36 -0800 (PST), Algis Kuliukas <...@kuliukas.com
This is the thread I set up for this purpose.
There is a lot of evidence placing early hominids in gallery forest
habitats. Jonathan Kingdon wrote a whole book based on the concept so
it is not something I suspect many paleoanthropologists would have a
problem with. Kingdon has scores of references of primary data to back
up his claim. The entire savannah-haypothesis is practically based on
it too as it acts as a vehicle for placing forest adapted hominids
into the savannah.
Gallery forests are adjacent to permanent water courses such as rivers
and lakes. That's why they are there. Savannahs are subject to
seasonal rainfall. That's why they are called savannahs. Now, put the
two together and you get river systems that flood seasonally. Add to
that the evidence from Potts (1998) which shows that the last 10My has
been characterised by increased seasonality and more infrequent shifts
in climate from wet to dry and back again and one can conclude that
the phenomenon of seasonally flooded gallery forests must have been a
key feature of the evolutionary landscape.
Gallery forests lack a continuous canopy. This is one of their key
attributes in helping to explain human evolution because even for a
fairly arboreal hominid, it is often forced to come down from the
trees to move from one clump to another. Note that this is not a
problem, but a positive advantage for savannah models because they too
need to explain a shift away from arboreal habitats to more
terrestrial ones.
Now put the two points above together. It is illogical to claim that
hominids would only have come down from the trees when it was dry and
never when habitats were flooded. Clearly, in seasonally flooded
gallery forests, hominids would sometimes have been compelled to get
down from the trees and wade through the water.
The evidence from extant apes is unequivocal. In shallow water apes
are far moe likely to move bipedally than on dry ground. In waist deep
water they really have no choice, other than to swim - and no ape,
apart from the gorilla, is known to swim regularly. Even gorillas,
however, have been reported to switch to bipedalism in shallow water
rather than continue to move bipedally. (e.g. Doran& McNeilage,
Alistair 1998; Parnell & Buchanan-Smith, 2001; Breuer et al 2005)
Therefore it is highly likely that seasonally flooded gallery forests
are the ideal habitat to induce hominids to move bipedally more than
they would otherwise do in habitats that are more extreme either in
terms of being more open or more closed.
The sort of selection that is likely to have aided bipedal wading is
exactly the same sort of selection that would make a hominid more
bipedal and move it closer towards, and then beyond, some rubicon at
wich point it would no longer practice quadrupedalism even on dry
land.
Seasonally flooded gallery forests offer very clear cut selection. The
risk of losing one's balance and being washed away is very real. It is
a scenario that offers greater selection for bipedalism than any other
model because there are depths that would simply kill you to move
quadrupedally.
What sort of phenotypic traits might be selected for? Clearly, traits
such as having longer legs, flatter feet and a lower back that is more
upright orientated. These, it should be noted, are exactly the sort of
traits that would make quadrupedalism on dry land more difficult and
bipedalism easier. As early hominids were exposed to regular (if
slight) selection from wading more than the ancestors of Pan/Gorilla
it is logical that this could have been the key factor causing the
divergence.
I've posted similar arguments in the past but, of course, you ignore
them,
I've addressed these questions before but you always avoid the
material points I make. You clearly don't want to undderstand the
points being made here.
I apologise if I missed any questions. The threads are quite branched
now. I haven't got time to read all the posts.
The points I make here are not new. What would be new is an effort
from your part to actually consider them instead of the usual knee-
jerk dismissal.
Algis Kuliukas
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On Wed, 24 Dec 2008 16:02:17 -0800 (PST), Claudius Denk <...@sbcglobal.net
On Dec 24, 3:25 pm, Algis Kuliukas <...@kuliukas.com
Everybody knows this already. Do you have anything new to say?
Jonathan Kingdon wrote a whole book based on the concept so
This is generally the case. But it's not absolutely the case.
Moreover many locations in a gallery forest may be miles from water.
Occasionally it might flood but it wasn't anything that they couldn't
generally avoid simply by going to higher ground.
Absurd, misguided, speculative nonsense. You, Algis, are a cultist.
Not a scientists. Stop fooling yourself.
Unequivocal and unremarkable.
In shallow water apes
This is rather obvious lunatic reasoning here. If you throw an ape
off a cliff and it flaps its arms as it falls is this evidence that
hominids went through a flying phase.
You display complete ignorance of natural selection.
Keep in mind that the rest of us don't have access to your
imagination.
You're becoming delusional.
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On Thu, 25 Dec 2008 16:44:37 -0800 (PST), Algis Kuliukas <...@kuliukas.com
On Dec 26, 1:03 am, mclark <...@comcast.net
No, but that is simply a matter of personal preference. He sees the
outside edges of the gallery forests as key - places where his
peculiar 'squat feeding' idea could be practiced by his 'ground apes'.
(An interpretation, I might add, for which there is no evidence
whatsoever - but I don't here you attcking him for it) I see the
inside edges of those same gallery forests as being much more
important because that is where wading would compel bipedalism. Even
if Kingdon had made such a statement you would have just dismissed it
as opinion, but when he doesn't you treat it as evidence.
There's no evidence they didn't either. In fact there's no evidence
they moved in any particular substrate really apart from trees. The
argument continues...
Early hominids lived in gallery forests. Gallery forests are part of
the savannah biome. Savannahs are subject to seasonal rainfall
therefore gallery forests are subject to seasonal flooding. In the
past, climatic patterns varied even more causing this flooding to have
been more extreme. Which part does not follow? Potts' whole paper is
about increased variability in climate in the past - hence his VS
(variability selection) hypothesis.
Can't you see how you're just clinging on, desperately, to any glimmer
of hope rather just accepting the basic tenet of the argument?
I am not making a straw man argument against the "savannah theory". I
don't need one. The idea that human bipedalism evolved purely in trees
is almost as bad anyway. I'm just making the point tthat your beloved
field of paleoanthropology has made the same assumption as me
regarding gallery forest habitats for generations - that their lack of
canopy would have forced them down onto the ground. That's all that's
needed here. And, of course, in seasonally flooded gallery forests
they'd have to wade. And the more wading they did the more bipedalism.
It's really very easy.
In contrast Crompton's "Hand-Assisted, thin-branched tree-wobbling
hypothesis" is very difficult to understand. Have you read it yet? If
so maybe you can tell me how this model explains Human-Pan/Gorilla
divergence? According to their model, all the great apes were already
somewhat bipedal so presumably *something* happenned to make our
lineage continue being bipedal whilst making Pan/Gorilla knuckle-
walkers but they're not very clear on that (understatement). Can you
please tell me what it is, because they don't seem to want to.
This is the state of play in paleoanthopology today. When faced with a
creationist looking them in the eye, asking "Ok, so what's the
Darwinian explanation for bipedalism?" The answer is "We don't know.
It was probably random drift". Great. What amazing progress we've made
in 150 years. All that tax payers research funding FOR THIS? And all
the time the most bleeding obvious factor, the one a three-year old
could spot, is ignored because that would cause embarassment to the
authorities. It's a complete shambles and you defend it.
Some may support the arboreal explanations, but you are naive if you
think it has reached anything resembling a consensus. Far more
"authorities" still cling to savannah explanations or "watered
down" (not in the true sense though, unfortunately) versions of them.
You have not given me any argument against my "two points" only hand
waving about lack of evidence - as if there'd be video footage or
something. Any open minded person can see that gallery forests would
induce more wading hominids than either open plains habitats or closed
canopy habitats. As they indice more wading, they would also induce
more bipedalism. Simple. It's clearly a factor that HELPS explain
bipedalism but you seem to be bizarrely against this help. You'd
rather no progress was made that have to admit you've been wrong on
this. Typical.
This is where I either have to conclude that you're an idiot, ot that
you have to continue to pretend to misunderstand the point because
even you can see how it clinches the argument. The whole idea of the
model is, Michael, (for the Nth time) that it was OUR ancestors that
lived in waterside habitats MORE than THEIR ancestors. That is what I
have been arguing for 13 years and you still don't get it. It's the
fact that there was GREATER SELECTION for moving through water in OUR
lineage, compared to THEIR'S that made us different.
There was INsufficient selection in THEIR lineage but ENOUGH in
OUR's.
Apes switch to bipedalism for a variey of reasons, true. But none is
so compelling as waist deep water. If you deny that you show that
you're not capable of the most basic requirement of a scientists: the
ability to make an observation.
Faulty criticism.
In waist deep water, even you would not try to stand on four limbs,
although I'm sure you'd try just to prove me wrong.
Australopithecines have longer legs, compared to forelimbs, than
chimps. That's all the comparison we need. That's one of the main
reasons why bonobos (rather than chimps) were chosen by Zihlman as a
model for australopithecines. Lower inter-membral index.
Longer legs, of course, would compromise better climbing and so
there'd be some counter-selection too. Once Homo came down from the
trees properly, this counter-selection was removed and the legs got
significantly longer.
Flatter than chimps, of course. It's related to striding bipedalism
today of course - no dispute there. But wading acts as a perfect
precursor for anatomical changes in the foot.
Only in your closed mind, I haven't.
Only in your closed mind.
Only in your closed mind.
You simply deny the undeniable and defend the indefensible.
Rubbish.
Rubbish. I can and have answered all your "arguments".
Exactly. You don't see anything. First lesson for a scientist: Open
your eyes and make objective observations. You fail even that test.
Algis Kuliukas
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On Thu, 25 Dec 2008 23:30:47 -0800 (PST), Claudius Denk <...@sbcglobal.net
On Dec 25, 4:44 pm, Algis Kuliukas <...@kuliukas.com
Aha. So you admit that Kindon never made reference to these gallery
forest being fllooded and A'pith having to wade. Right?
You shouldn't pretend to speak for him on this point.
He's not presenting it here.
Speculative, absurd, nonsense.
If you had quoted Kindon in an intellectually honest manner you'd have
explained to your audience that Kingdon does not support your model.
Doesn't common sense dictate the conclusion that they'd generally tend
to avoid/flee flooded areas?
You're beating a dead horse on this point Algis.
No. You're wrong Algis. It's been known/assumed for quite some time
now that apes have always used the ground to get from one location to
the next. So, as Clark suggests, you are presenting a strawman.
Aha. So, IYO, a compelling reason for them to go into such water is
not needed? They would just naturally take to water?
What do you mean, "the" aboreal exlanations?
It's more of a cult than a consensus. They all agree to pretend that
they have a common understanding that isn't perfectly vague. And they
attack anybody politically that draws attention to the fact that they
can't answer even the simplist questions.
Far more
Your points aren't based on evidence. They're based on amateurish
speculation.
only hand
Which is irrelevant to a scenario describing the selective origins of
obligate bipedalism. You first need to undestand the concept of
natural selection.
Simple. It's clearly a factor that HELPS explain
This isn't a model you retard!
That is what I
Absurd, speculative, nonsense.
How is waist deep water compelling to an ape? How's about answering
this question you evasive jackass?
If you deny that you show that
It's regrettable we don't have direct access to your imagination.
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On Sat, 20 Dec 2008 16:16:32 -0800 (PST), rmacfarl <...@alphalink.com.au
...
After a week of to-ing & fro-ing on this subject, the state of play is
this:
- There is evidence that early hominids around the time of the LCA may
have lived in "gallery forests" - those which have a relatively open
canopy and which are subject to seasonal flooding.
- Whether these were the only places hominids were found,
how often they flooded, and how open or closed the canopies
were, are matters of speculation.
- Having now placed hominids in an environment where the ground is
flooded part of the time, Algis then switches on his long-held
"bipedal wading in waist-deep water selective scenario", and considers
the problem of the evolution of bipedalism solved.
- Alternatives to the scenario, such as not wading waist-deep
in the flooded forest, and all of the long-identified problems
with
wading as a selection mechanism, are ignored or dismissed.
Ultimately that is it. Top to bottom, end to end, that's all you have
Algis.
It's not enough. Case closed...
Ross Macfarlane
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On Sun, 21 Dec 2008 04:54:03 +0100, Marc Verhaegen <...@skynet.be
1) fossil approach (scanty = biased):
All early hominid fossils in Africa 10-6 Ma come from milieus with a mix of
water, trees & grasses (10-7 Ma more open, 7-6 Ma less open?): Chororapith,
Nakalipith, Samburupith, Sahelanthr, Orrorin.
- If European Oreopith is included in hominids: coastal swamp forest.
- If Ouranopith is included: more open wetlands (cf.robust apiths later).
Later, gracile apiths 4-2 Ma lived in swamp forests.
Still later (Pleistocene forest reduction), robust apiths 2-1 Ma lived in
wetlands.
2) evol.approach:
The H/P LCA probably lived in Africa c 5 Ma. There were 2 large forests in
Mio-Pliocene Africa (Jon.Kingdon): the Kongo-Nile-Rift central forest & the
Ind.Ocean littoral forest. Since Pan & Gorilla developed in parallel, they
were probably allopatric:
- G in the central forest (fits the resemblances of A.afar.aeth.boi with G),
- HP in the coastal forest (resemblances of A.afr.rob with Pan).
At the time of the H/P split, P at first stayed in the E.Afr.forest, the H
"offshoot" colonised the Ind.Ocean shores.
concl.:
Not so much gallery forest, but rather low swamp forests, and in the case of
the H/P LCA probably more specifically coastal forests (which don't
fossilise well).
Yes, possible.
Yes, wading (alone) doesn't explain bipedalism: wading mammals are typically
quadrupedal.
The only indication AFAIK is Nasalis wading & often running on 2 legs in
mangrove forests http://en.wikipedia.org/wiki/Proboscis_Monkey : these
monkeys are the largest colobines, good swimmers, sometimes climb arms
overhead, Nas.concolor has a shortened tail, Nas.larvatus an ext.nose: first
steps towards aquarborealism?
Human present-day bipedal locomotion evolved in many steps:
- One of the first was vertical posture-locomotion in early apes (gibbons &
humans are still vertical): hanging + floating &/or wading in densely
vegetated swamp forests (probably coastal, see hominoid migration to
Eurasia). This explains in what hominoids differ from monkeys: broad body,
larger weight, tail loss, below-branch locomotion, tendency to verticality
etc.
- Possibly the hominid at the time of the HP/G split c 8 Ma regularly waded:
the early hominid fossils were remarkably large & gorilla-like, but with
thicker enamel (Chorora-Nakali-Samburupith): I guess they waded-floated a
lot in rel.open swamp forests, much like lowland gorillas still do, but more
frequently, feeding on aquatic herbs (Ndoki gorillas), but also on
low-calorie grasses (sedges, papyrus... eg, in poor season) &/or
hard-shelled invertebrates (google "Shabel durophage") + nuts, fruits etc.
- After the H/P split c 5 Ma, Homo lived around the Ind.Ocean, at first in
littoral forests-deltas, later (Pleistocene) in more open tree-poor milieus
diving (pachyostotic archaic Homo) & beach-combing (esp.women-children?),
collecting cray-shellfish, turtles, eggs, dugongs, possibly sea or lagoon
plants & occasionally (but better-preserved archeologically) stranded whales
& trampled bovids. Side-branches appear in the Rift with high sea levels
(esp.2.5, 1.8, 1.2 Ma), and in Europe with warmer climates
(H.antec.heidelb.neand).
- H.sapiens in Africa-Arabia-Ind.Ocean (after c 200 ka?) reduced diving &
became more dependent on freshwater (wading, boats, nets...) & later more
strongly terrestrial (some tribes even evolved kudu running eventually).
--Marc Verhaegen
http://users.ugent.be/%7Emvaneech/Verhaegen%20et%20al.%202007.%20Econiche%20
of%20Homo.pdf
http://users.ugent.be/~mvaneech/Verhaegen%20&%20Munro.%20New%20directions%20
in%20palaeoanthropology.pdf
http://groups.yahoo.com/group/AAT
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On Sat, 20 Dec 2008 20:21:15 -0800 (PST), Lee Olsen <...@hotmail.com
On Dec 20, 7:54 pm, Marc Verhaegen <...@skynet.be
"Moreover, the depositional context of isolated hominin
fossils may not provide a clear indication of
habitat preference during life (White, 1988). As reviewed
by Sikes (1994), there is little consensus
regarding Plio-Pleistocene hominin habitat preferences
in East Africa."
Thomas Plummer
Flaked Stones and Old Bones:
Biological and Cultural Evolution at the
Dawn of Technology
YEARBOOK OF PHYSICAL ANTHROPOLOGY 47:118–164 (2004)
Semi-aquatic mountain beaver imagination talk.
Semi-aquatic mountain beaver imagination talk.
Liar.
Loots of wetlloon talk here.
Yes, more likely you made that up, like you make up Stringer quotes.
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On Sun, 21 Dec 2008 13:35:17 +0100, Marc Verhaegen <...@skynet.be
somebody with "sporatic capasity" thought he should bring in here:
a) has nothing to do with the above (10-6 Ma)
b) not incorrect: we need other data too (esp.comparative)
c) omits the fossil evidence, eg,
- dentitional (+-all fossil hominids-pongids): thick enamel
- locomotor (apiths): vertical + hanging = swamp forests
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On Mon, 22 Dec 2008 16:44:41 -0800 (PST), Lee Olsen <...@hotmail.com
On Dec 21, 4:35 am, Marc Verhaegen <...@skynet.be
ROFL, this psycho, who starts a thread with "Ealine Morgan" is now
pretending to be an editor?
Good pervert, then none of those were associated with water, by your
logic.
The data you don't have except in your imagination.
Liar. No attribution marks again, boy are you stupid.
Savanna dweller Homo has thick enamel also.
Orangs live in swamp forests and avoid water.
Did you have a point, or is your imagination working again?
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On Mon, 22 Dec 2008 16:12:40 -0800 (PST), Algis Kuliukas <...@kuliukas.com
On Dec 22, 9:01 am, rmacfarl <...@alphalink.com.au
What Ross fails to mention is actually the KEY argument: I suggested
that gallery forests were more important in hominid evolution than in
chimp evolution. I never suggested they ONLY lived in such places,
only that they did so more than chimps.
Ross' reply to this was that we know nothing about where chimps lived
because there is no fossil evidence for them. To which my response
was
that this has not stopped two generations of paleoanthropologists
being taught that humans moved into open habitats more than chimps.
Ross' non-response was to avoid the subject.
I also made the point that the very discrepancy between the number of
fossils found attribtuted to human ancestors (thousands) compared to
those attributade to chimps (1?) is easiest explained by the fact our
ancestors lived (and hence died) in waterside habitats more than they
did. But Ross didn't like that either.
It's certainly a factor that has not been considered enough by the
field of anthropology. It's certainly the factor that gives the most
blatant and clear cut selection for bipedalism and it's certainly the
factor with the most compelling evidence in extant apes. It is
consistent with the fossil evidence and it is also very compatible
with almost all the other models.
So, yes, it certainly helps to solve the problem that has eluded an
entire field for 150 years. It seems so silly to continue to argue
against it only to defend egos and reputations.
That is simply not true. I have never, do not, and never will dismiss
all other models. I have repeatedly said that arboreal models are
certainly a pre-requisite for any other, that carrying models are
clearly a part of the solution, that postural feeding has very good
evidence for it and that the energy-efficiency model is almost
certainly true for the later stages of human evolution. I am not
against most other models at all. On the contrary I think a key
aspect
of the wading hypothesis is how very compatible it is with all other
models. All I claim is that the wading model is by far the strongest,
not that is the only one that can have been part of the solution.
Wading brings all th ether models together and strengthens them. But
Ross childishly pretends that I'm arguing for exclusivity only
because
it makes him think it helps him defeat it.
More distortions. The fact bonobos have characteristics more
indicative of bipedalism is a good evidence against more open
scenarios for hominid bipedal origins but either way, no such
evidence
supports that our ancestors were "aquatic".
That Ross peddles such a misrepresentation even after all these years
shows he has not made the slightest effort to understand the most
basic point that some of us are trying to argue.
He is simply a time waster. As usual, the only real arguments against
waterside hypotheses are to distort and misrepresent them.
Algis Kuliukas
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On Tue, 23 Dec 2008 19:17:09 -0800 (PST), rmacfarl <...@alphalink.com.au
On Dec 23, 11:12 am, Algis Kuliukas <...@kuliukas.com
You also state that Pan evolved in the same place in another post,
which is somewhat confusing.
I don't accept that there is enough evidence to clearly place the LCA
in the gallery forests because there is too much chance that this
interpretation is due to taphonomic bias - i.e. we haven't found the
fossils in other localities. I'd also point out that the australopiths
that you are citing post-date the LCA by a margin which may be several
million years.
Algis, so what? Honestly, we can all see and understand your
frustration that the world's not listening to you, but it doesn't stop
you pushing the idea - and nor should it.
You say I haven't responded to this issue, but I have, and my response
is to say "so what?" What can you do about it, except *try to do
better science*, and prove your point. But I'm sorry, I've looked, and
I've listened, & I so far I haven't see that happening.
I'll allow the possibility just to move the argument along, but I take
it you acknowledge there are other explanations for this taphonomic
bias, & that not everyone would agree that yours presents the
"easiest" explanation?
That is not why people argue against it Algis. And even if it was,
complaining about it won't solve the problem.
If you think it helps to solve the problem, you have to produce the
science to back it up.
It is a fact of life when someone challenges the status quo that they
have to actually do better than anyone has ever done before. Like the
first woman to work in a male-dominated work area, or the first black
man to play major-league baseball.
That's your challenge. Your arguments lead me to believe you're a long
way from achieving it yet, but stick at it. You might yet succeed in
convincing the mainstream that wading probably was a significant
factor in evolution of bipedalism, and if anyone deserves to it is
you.
If you want my advice, and I doubt that you do, I think you should
keep trying to get your paper published & your PhD awarded. Find out
what factors led to the paper being refused, and address them. Don't
waste your time here on SAP.
[I withdraw other assertions which Algis specifically repudiates.]
[Bloody spirit of Christmas, peace on Earth & good will to all men
rubbish. Bah, Humbug!]
Ross Macfarlane
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On Tue, 23 Dec 2008 22:40:46 -0800 (PST), Claudius Denk <...@sbcglobal.net
On Dec 23, 7:17 pm, rmacfarl <...@alphalink.com.au
Ross likes to talk big but he doesn't have a good understanding of
taphonomy. Rainforest habitat completely (or almost completely)
eliminates fossilization because there is no soil formation (heavily
leached soils) and because there is no dry season. Conversely the
reason the resolution of hominid fossils (and associated biota) is so
good is because the climate had shifted from rainforest to a climate
that had a significant dry season.
All of the best evidence is consistent with hominids living at well-
watered, well-treed localities of a greater savanna-like, monsoon
forest, geographic/climatic region. There is no evidence of hominids
in treeless savanna habitat.
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On Wed, 24 Dec 2008 03:55:28 -0800 (PST), Algis Kuliukas <...@kuliukas.com
On Dec 24, 12:17 pm, rmacfarl <...@alphalink.com.au
Actually I am not myself absolutely convinced that australopiths were
ancestral to humans, although it seems a reasonable assumption to
adopt here, considering the evidence. They may have been ancestral to
chimps, both chimps and humans or neither. I'm assuming they're
ancestral only to humans here for the sake of clarity and brevity.
They may well have lived in other habitats too, but based on what
evidence we have, it seems churlish to deny what the mainsteam seems
to assume here: that australopithecines lived in gallery forests some
of the time. As we have no evidence for the chimps it's reasonable to
assume our ancestors lived in gallery forests more than they did.
After all, it is the very same assumption really that the savannah
paradigm is based upon. Yves Coppens' East Side Story and all that. We
lived east of the rift, where it got drier, they lived west of the
rift where it stayed relatively wet. I'm actually agreeing here with
some of the savanah paradigm. All I'm saying is that as climate
changed, forests didn't shrink randomly but systematically closer to
permanent water courses. It is logical that out hominid ancestors
would have clung to gallery forest refugia during these times of
change.
I don't think "So what?" is an adequate response. You can't have it
both ways: If you complain that gallery forests are not really backed
by strong evidence for hominids over chimps, you must concede the very
same against the savannah - and this has been mainstream for 60 years.
If you accept the savannah paradigm, that our ancestors lived in
different habitats from chimps, then you have to accept the gallery
forest part too.
Of course. I'm not arguing for exclusivity anywhere here. I'm just
saying that the huge discrepancy in the number of fossils is easily
explained by watersdie hypotheses (as usual) other explainations are
possible but (as usual) they are less parsimonious and more
convoluted.
I'm sure it is not why many people argue against it. But I am sure it
is in the back of the mind of some. Complaining about it will
hopefully make those people feel a little guilty about their
intellectual cowardice and start being a little more open minded and
scientific.
I've tried to do the science but it was rejected. It's a catch 22.
Fair point but I think I have done better than many. What other model
of hominid bipedalism can show such strong and immediate selection,
such good evidence in extant apes, such clear links with wetland
paleohabitats and such a clear cut way of solving the 'rubicon'
problem for energy efficiency?
Well, thanks, Ross. That is a most unexpected and kind thing to
write. :-)
Well thanks for that advice too, Ross. I think you're right. I
certainly intend to try again to get the paper published and, if it
is, I will probably then be sufficiently motivated to get the damned
PhD finished too. But right now i'm on a scientific sabatical and
whilst that goes on I'm enjoying the pointless arguments I can find
here.
Thanks for making the effort to find a better tone for this debate,
Ross. I really appreciate it. I'm sorry for the hostile things I've
written about you in the heat of the moment. I still consider you to
be one of the more decent people on this newsgroup.
Merry Christmas to you too and eyes glued to the tely for Australia v
South Africa on boxing day.
All the best
Algis Kuliukas
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On Thu, 25 Dec 2008 13:24:01 +0100, Marc Verhaegen <...@skynet.be
Most probably apiths are not ancestral to humans:
- They overlap Homo (eg, Dmanisi, Mojokerto 1.8 Ma, robust apiths until 1.2
Ma), so one of these is less closely related to us.
- They have nothing uniquely human: their so-called humanlike features are
primitive for hominids (sensu Pan+Homo+Gorilla), eg, thick enamel, vertical
locomotion.
- Their airsacs, small brain, rel.short legs, some KWing features etc. are
only seen in apes (KWing only in chimps & gorillas).
- PAs think they've found thousands of fossils of so-called relatives of
humans, but 0 or 1 relatives of chimps... not so likely IMO.
The H/P LCA probably looked a bit like an apith (thick enamel, vertical
hanging-wading etc.), but apiths were already derived in the Afr.ape
direction IMO: partial KWing etc., lived in forest swamps & wetlands
(papyrus swamps at Olduvai), a bit like when today's lowland gorillas feed
in swamps (google "Ndoki gorilla).
--Marc
Nutcracker munching on papyrus?
http://www.iol.co.za/index.php?set_id=1&click_id=588&art_id=vn20081024054331
926C144608 in imitation of our Human Evolution papers, eg,
"Did robust australopithecines partly feed on hard parts of Gramineae?"
Hum.Evol.7:63-64, 1992,
and with P.-F.Puech "Hominid lifestyle and diet reconsidered:
paleo-environmental and comparative data" Hum.Evol.15:175-186, 2000:
"Olduvai middle Bed I: A. boisei O.H.5 as well as habilis O.H.7 and O.H.62
were found in the most densely vegetated, wettest condition, with the
highest lake levels (Walter et al.1991), near ostracods, freshwater snails,
fish, and aquatic birds (Conroy 1990); the middle Bed-I faunas indicate a
very rich closed woodland environment, richer than any part of the
present-day savanna biome in Africa ¹ (Fernández-Jalvo et al.1998).
Fossilized leaves and pollen are rare in the sediments of Beds I and II,
but swamp vegetation is indicated by abundant vertical roots channels and
casts possibly made by some kind of reed. Fossil rhizomes of papyrus also
suggest the presence of marshland and/or shallow water¹ (Conroy 1990).
Cyperaceae fruits were common in H. habilis habitat (Bonnefille 1984).
Ancient Egyptians ate Cyperus papyrus root which was also present at Olduvai
in swamp-margins and river banks¹ (Puech 1992)."
cf. (google "Olduvia papyrus"):
Swamps, springs and diatoms:
wetlands of the semi-arid Bogoria-Baringo Rift, Kenya
Hydrobiologia 518:59-78
RB Owen, RW Renaut, VC Hover, GM Ashley & AM Muasya 2004
Lakes Bogoria & Baringo lie in a semi-arid part of the Kenya Rift Valley
between 0°15'0°30'N & 36°02'36°05'E. Nevertheless, the area around these
lakes contains numerous wetland systems that have been formed: along lake
shorelines; along faults where hot, warm & cold springs have developed; &
along river systems that cross the rift floor.
6 major types of wetland are recognized:
- Proximal Hot Springs;
- Hot Spring Marshes;
- Blister Wetlands;
- Typha & Cyperus papyrus Swamps;
- Floodplain Marshes;
- Hypersaline Lake Littoral Wetlands;
- Freshwater Lake Littoral Wetlands.
These show significant variability in terms of geomorphic setting, water
chemistry, temperature, plant communities & diatom floras. They are
variously dominated by macrophytes (Cyperus laevigatus, Typha domingensis,
Cyperus papyrus). In some cases macrophytes are absent. In hot spring
settings & in hypersaline lake littoral zones, bacterial mats are common.
Although absent in some samples, diatoms occur in at least parts of all of
the wetlands, varying in diversity, abundance & species composition.
Canonical correspondence analysis indicates : diatom floras show a close
relationship with pH, temperature & specific conductivity, with other
environmental variables such as Si & nitrate being of secondary importance.
Common diatoms include: Anomoeoneis sphaerophora var.guntheri, Navicula
tenella, N.cuspidata, Nitzschia invisitata in hot springs, where diversity
is generally low and abundance is variable. Other wetland types contain
distinctive diatom floras that variously include: Fragilaria brevistriata,
Gomphonema parvulum, Navicula tenelloides, Nitzschia communis, N.latens,
N.sigma, Rhopalodia gibberula & Stauroneis anceps.
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On Wed, 24 Dec 2008 09:07:06 -0800 (PST), Claudius Denk <...@sbcglobal.net
On Dec 24, 3:55 am, Algis Kuliukas <...@kuliukas.com
Churlish is a perfect description of Ross. (Don't let Ross fool you.
He knows full well that gallery forests [ie. garden-habitat in monsoon
forests] are the original hominid habitat. He is avoiding admitting
this not because of you. You are his strawman. He is avoiding
admitting this because of my hypothesis.)
This is obvious. Ross is only pretending to not understand/believe
this. Pretending to not understand is a very common tactic amongst
scientific loons. Another example of this pretending to not
understand is Paul Crowley as he pretends to not understand how A'pith
would be largely if not completely safe from predation in treed
habitat. And another example of this is yourself pretending to not
understand that there would hardly have ever been a reason for early
hominids to wade in waste deep water.
Obviously.
Ross is an evasive jackass. He is fully indoctrinated into the anthro
cult and sees it as his righteous agenda to pretend to not understand
anything that will reveal the truth the hominids are group selected.
Ross doesn't take you seriously, Algis. You are justl a strawman to
draw attention away from the real issues.
Algis, you are up against a wall of intellectual dishonesty supported
by a mountain of taboo-inspired tradition. Ross has no intention of
admitting that the evidence clearly indicates the communal nature of
hominids at the garden-like locations (gallery forests) of a monsoon-
forest habitat. His goal is only to keep it vague so that my
hypothesis doesn't get more attention.
Typical AAT dimwittedness. The truth, Algis, is that early hominid
fossils are never associated with waterside habitat specficically.
Rather it is associated with garden-like treed localities that are
generally in the vicinity of water.
It's funny how you are trying to take Ross to task for his
intellectual dishonesty and now you do the same thing. You aren't
fooling anybody. You are not a scientists, Algis. You have an
agenda. And, like Ross, you bend all you observations to fit that
agenda.
Pot calling the kettle black.
Dimwitted nonsense. You've proven yourself incapable of taking an
objective stance when examining evidence. This alone is enough to
dismiss you as the loon you really are.
You're not fooling anybody Algis. (But Ross is fooling you.)
Absurd, speculative nonsense.
He's just using you as a strawman you idiot.
Sucker.
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On Fri, 26 Dec 2008 14:45:14 -0800 (PST), rmacfarl <...@alphalink.com.au
On Dec 25, 4:07 am, Claudius Denk <...@sbcglobal.net
Jim, I would just like you to know that you are a pig-ignorant fool
and wrong in practically every aspect of your "analysis", and yes, I
am deliberately ignoring you.
Happy New Year.
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On Fri, 26 Dec 2008 22:50:41 -0800 (PST), Claudius Denk <...@sbcglobal.net
On Dec 26, 2:45 pm, rmacfarl <...@alphalink.com.au
Try harder.
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On Fri, 26 Dec 2008 15:17:30 -0800 (PST), rmacfarl <...@alphalink.com.au
On Dec 24, 10:55 pm, Algis Kuliukas <...@kuliukas.com
If you are going to revive Marc's arguments about australopiths being
ancestral to Pan &/or Gorilla, I will certainly be dropping any idea
that your idea for bipedal origins is as mainstream or as supported by
evidence as any other. It is very clear that this can't be supported
by a cladistic analysis at any level.
No problem with either of those statements but it makes it hard to
make a case for a bipedal wading origin as anything more than a
speculation.
Which seems to have been what Gorillas & Pan did. An alternative view,
equally logical, is that some would have found a way to survive in the
expanding savannah habitat. (I am not promoting this view, just
pointing out that there are other alternatives to the ones you
promote.)
You've missed my point again. I'm not defending the "savannah
paradigm", or denying the gallery forest, or taking a position on any
part of it. I'm talking about what you need to do in order to
demonstrate that any prevailing paradigm needs to be jettisoned or
modified by your position.
History shows that to have a radical hypothesis accepted, you have to
do *better* science than the mainstream. Putting up something that's
just as good will not cut it. Whether this seems unfair or not, it is
human nature.
Good luck...
Ross Macfarlane
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On Sat, 27 Dec 2008 10:14:22 +0100, Marc Verhaegen <...@skynet.be
SF who believes he descends from an apelike creature with airsacs, short
legs, curved phalanges, no external nose, small brain, rel.long toes etc
...:
My boy, apiths had thick enamel & a vertical locomotion, but these features
are ancestral to all hominids-pongids :
recent confirmation of our idea that A.boisei ate reeds/sedges etc. in
wetlands:
Isotopic evidence for contrasting diets of early hominins Homo habilis and
Australopithecus boisei of Tanzania
NJ van der Merwe, FT Masao & MK Bamford 2008 S.Afr.J.Sci.104:153-5
... at 1.8 Ma, there were extensive wetlands on the Eastern side of
palaeo-lake Olduvai, where a river entered the lake from the Ngorongoro Mtn
range; at 1.5 Ma, the Peninj River flowed into Lake Natron from the West, as
it does today, and also produced wetlands.
One of the authors has identified fossilized plant remains from
Olduvai-East. Most were of woody plants, but ~5% were sedges. These are
identifiable from their triangular cross-sections, but it is not possible to
determine whether they were of the C4 photo-synthetic type. They were
rel.small sedges (stem diameters <1 cm), probably of the type that grows in
the seasonally inundated grasslands on the edges of a wetland. B+vdM
investigated & ate the edible plants of the Okavango Delta in Botswana
during the dry season (July¹03), assisted by Ezaya Karesaza (tourist guide,
grew up in this extensive wetland).
Among the C3 plants that are traditionally eaten raw in this region are a
variety of fruits & seeds, & plants of which the leaves & rhizomes are eaten
incl.
- Aeschynomene fluitans (floating leguminous plant, leaves taste like
lettuce),
- Typha capensis (grows in thick stands along the water¹s edge, rhizomes
have apleasant taste) ,
- Schoenoplectus corymbosus (big water sedge, stem is succulent at the
bottom end).
Among C4 plants, the rhizomes & culms of 3 other spp of sedges are edible
incl.Cyperus denudatus & C.dives (grow in the grasslands of the
floodplains). Unlike the grasses, they are green year-round, although not
particularly prolific. The most common C4 sedge is Cyperus papyrus (grows in
dense thickets along the water edge). This sp has culms as high as 4 m , the
lowermost 0.5 m is frequently chewed by local people. It has a soft, white
rind ~0.5 cm thick; the interior, ~2-3 cm in diameter, is more fibrous. It
is chewy & pleasant tasting. The thick rhizome of papyrus is more fibrous &
starchy than the culm, somewhat astringent, and requires considerable
chewing effort. It produces a bolus in the mouth that has to be spat out at
intervals. The nutritional qualities of papyrus compare quite well with
those of the domesticated potato Solanum tuberosum. ... papyrus rhizome &
culm have more CHOs & fat than potato, but somewhat less protein, ~2 kg of
raw papyrus rhizome could supply the daily energy requirements of a human
adult , only possible if humans had the intestinal enzymes & bacteria to
digest raw cellulose, as apes do.
(& everybody except a few loons here knows that apiths were fossil apes)
Humans do not have this capacity, but it is not beyond the realm of
possibility that an early hominin such as A.boisei did have it. It is not
our intention to suggest that A.boisei had a staple diet of papyrus, but to
offer this plant from the permanent freshwater swamps as a strong candidate
for a major role in its diet, along with other C4 spp of Cyperaceae that are
tolerant of brackish water. In the first place, such a major role could not
have been played by C4-consuming animals. Humans are limited to ~2050 %
protein-rich foods for their energy requirements (excess protein consumption
leads to protein poisoning with potentially fatal consequences).
A.boisei clearly had a substantial dietary intake of C4 plants :
- grasses could have supplied part of this diet, particularly in the form of
seeds, this dietary item is highly seasonal ;
- Cyperaceae are perennials, available in all seasons in the vicinity of
water. Papyrus is a particularly good candidate for a C4 plant diet, since
it is such a prolific producer. As measured at Lake Naivasha in Kenya, it
produces 6.3 kg/m2/yr (dry Wt), among the highest productivity recorded for
natural ecosystems. It grows in shallow water, the whole plant can be
pulled from the mud with some muscle power. While papyrus has not been
identified among the fossil plants of Olduvai-East, this is probably the
result of a lack of preservation, not an absence of the sp. Fossilized
papyrus has not been identified at Peninj either, but there are dense stands
of papyrus today, where the Peninj River flows into Lake Natron ...
:-)
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On Fri, 26 Dec 2008 16:49:54 -0800 (PST), Algis Kuliukas <...@kuliukas.com
On Dec 27, 8:17 am, rmacfarl <...@alphalink.com.au
The two questions are quite independent, in my view. The actual status
of that group of fossils labelled australopithecines is unknown. Any
cladistica analysis of bony bits and bobs should be taken with a pinch
of salt. They completely ignore epigentic factors.
Whatever th status of australopithecines vis-a-vis Homo, the case for
wading as a factor in the origin of hominid bipedalism remains strong,
although clearly it would be benefitted if australopithecines were
ancestral to Homo,
It's all speculation, Ross. I admit that much. All we can do here is
look at the competing models and ask which ones help most, which ones
are more plausible and which ones have most evidence. I think the
wading model gets a tick in all three boxes there.
Again, it's possible and, again, I'm not saying it didn't happen. I'm
just saying that it is likely that they'd have lived in gallery forest
refugia MORE than the chimps and gorillas did. If we are looking for
reasons for Human-Pan divergence in terms of locomotion I can't see
how anyone could argue that this wasn't helpful.
Well that's a fair point and undoubtedly true, unfortunately (who gets
there first is king seems an odd way to do science).
I think I do do better. Wading gives more clear cut selection. It has
extremely good evidence in extant apes. The seasonally flooded wading
hypothesis is compatible with all the mainstream fossil evidence.
Wading models are compliemntary to almost all other models.
These are attributes very much in its favour.
Thanks.
All the best
Algis Kuliukas
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On Sat, 27 Dec 2008 14:02:14 +0100, Marc Verhaegen <...@skynet.be
SF:
never heard of parallelism & convergence, my boy??
Darwin based his theory on parallelism & convergence
SFs are stupid stupid stupid
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On Sat, 27 Dec 2008 06:36:21 -0800 (PST), Algis Kuliukas <...@kuliukas.com
On Dec 27, 5:32 pm, rmacfarl <...@alphalink.com.au
Cladistic analyses done on molecular data is very powerful but I
assume here, you're claiming that cladistic analyses done on bony
characteristics are "almost as powerful" as that. I must strongly
disagree with that. Bones are bones. They can change even during one
lifetime. They are affected by diet and various pathologies. Molecular
data, like DNA, on the other hand, will not change to any degree from
the moment of conception until death, it is not really affected by any
epigenetic factor and is therefore is a very reliable source of data
for inferring phylogeny.
I've done cladistic analyses on skulls and pelves and other bones too
and I have never felt confident about them. At UCL we were encouraged
to give a binary 1 or 0 for the presence or absence of a particular
"bony bit" and it was almost impossible to do. To infer that the
presence or absence of such a character is purely the result of
phylogeny is naive in the extreme.
Again, I don't agree. I think Marc is closer to the mark on this than
most anthropologists would have us believe, actually.
I personally think Marc goes a bit too far with his reliance on
examples of parallel and convergent evolution but I certainly think it
quite a reasonable idea that robust australopithecines may have been
ancestral to gorillas and that gracile forms may have been ancestral
to Pan.
The problem with this is that it replaces one fossil vacuum with
another. It swaps a lack of Pan/Gorilla fossils with a lack of pre-
Homo ones.
Marc and people like Michael Crawford would presumably argue that this
is not a problem at all - they'd argue that we just haven't found the
pre-Homo fossils yet as they were on the coasts.
They might be right and if they were it would certainly signal the
death knell for my seasonally flooded gallery forest model for the
origin of hominid bipedalism. Either way, I'm with them completely on
post-Homo evolution on the coasts.
Whether it was seasonally flooded gallery forests or coastal mangroves
- wading is the perfect complement to climbing to help explain more
bipedalism in my opinion.
I like the seasonally flooded gallery forest idea because it is most
compatible with mainstream ideas and the evidence used to support
them.
I still have a hunch - no more than that - that gracile
australopithecines may turn out to be ancestral to both Homo and Pan.
Algis Kuliukas
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On Sat, 27 Dec 2008 16:46:20 +0100, Marc Verhaegen <...@skynet.be
A lot of PAs (independently!) have suggested that apiths were ancestral to
the Afr.apes rather than to us. Little doubt IMO: it's incomprehensible
that there are still PAs who believe that apiths were human ancestors.
Some PAs (first prof.Kleindienst AFAIK) have suggested that
- robusts were in Gorilla,
- gracile apiths in Pan.
My hypothesis differs from Kleindienst's: IMO
- the E.Afr.apiths (aethiopicus, boisei & probably also (all?) afarensis)
belonged to Gorilla (which is not the same as saying that these fossils were
ancestral to living lowland or highland gorillas),
- the E.Afr.africanus-robustus belonged to Pan (which is not the same etc.).
There are very specific anatomical features which link the E.Afr.apiths to
Gorilla, and the S.Afr.apiths to Pan, see my Hum.Evol.papers:
1990. African ape ancestry. Human Evolution 5, 295-297.
1992. Did robust australopithecines partly feed on hard parts of Gramineae?
Human Evolution 7, 63-64.
1994. Australopithecines: ancestors of the African apes? Human Evolution 9,
121-139.
1996. Morphological distance between australopithecine, human and ape
skulls. Human Evolution 11, 35-41.
2000 with P-F Puech. Hominid lifestyle and diet reconsidered:
paleo-environmental and comparative data. Human Evolution 15, 175-186.
http://users.ugent.be/~mvaneech/Fil/Verhaegen_Human_Evolution.html
IMO my hypothesis can be (dis)proven by comparing the odontoglyphs of fossil
& extant hominid-pongid cheekteeth (wrinkling in tooth enamel, google
"odontoglyph(ic)(s)").
The HP/G split c 7 Ma fits
- the African tropical forest split into a central (Kongo-Nile-Rift) & a
littoral forest (Zambesi Ind.Ocean): G & HP resp., see Jon.Kingdon,
- the parallel evolution of G & P (allopatric).
The H/P split c 5 Ma also explains how Homo populations colonised the
Ind.Ocean shores & from there trekked inland along rivers.
The low sea levels during the glacials explain the "vacuum", but in fact
it's very vacuum: the first undoubted Homo (I'm not sure whether the
"habilis" fossils are closer relatives of us than of chimps or even
gorillas) come from Dmanisi & Mojokerto, both near lots of edible shellfish.
IMO archaic Homo was basically coastal (human newborns still have renculated
kidneys, typical of marine mammals), but later H.sapiens lived probably more
next to fresh water (human adults have smooth kidney surfaces & rather low
concentration power, almost like other mammals with access to plenty of
fresh water).
--Marc
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