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DPCrisp
In: Bedfordshire
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Those gophers' horns are pretty much up-and-back, like other terrestrial horns.
If no one can think of anything, praps my hunch was right: that forward-or-down horns or tusks belong only to aquatic animals: for stirring up grub from the bed, presumably. That includes rhinos and elephants. I'm not sure how serious she is about it, but a suggestion connected with the Aquatic Ape Hypothesis is that all -- curiously naked -- pachyderms have aquatic origins. The elephant's tusks and trunk are perfectly deployed for a sea/river/lake-bed diet, innit? And those shell-crushing teeth... and that snorkel... and they can swim... and they're brainy...
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Mick Harper
Site Admin
In: London
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Just seen a prog about chimps wandering around waist-deep in the water. Of course they were standing up on their hind legs because you can't do anything else. This presumably is the origin of our own bipedalism. Also the young chimps had to cling on for dear life, hence our only long hair being on our heads.
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Ishmael
In: Toronto
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That is Elaine Morgan's argument precisely.
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Mick Harper
Site Admin
In: London
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Yes, I hope nobody thought I was claiming it as my own. I am entirely a Morganian. The fact that I have never been able to come up with anything novel myself in this field is eloquent testimony of her brilliance.
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DPCrisp
In: Bedfordshire
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Elephants can stand on their hind legs, too. Is that unexpected? If they can float well enough to swim, can they also walk into water so deep they have to stand up to reach for a breath of air?
For humans, what about wading around in snow?
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Chad
In: Ramsbottom
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| The elephant's tusks and trunk are perfectly deployed for a sea/river/lake-bed diet, innit? And those shell-crushing teeth... and that snorkel... and they can swim... and they're brainy... |
I've got to agree, the evidence for an aquatic ancestry for the elephant looks pretty overwhelming. In fact everything about it looks so well adapted to a watery lifestyle that I'm left wondering why there are no members of the family elephantidae occupying that particular niche now, or in the recent past. The mammoth even went so far as to grow his hair back.
Is it just the case that following some environmental change, the ones that returned to the land got lucky - - while their aquatic cousins were left up shit creek without a paddle, so to speak? And is that also what accounted for the demise of our own aquatic predecessors?
If so, when did all of this transpire - - or is that a secret just yet?
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Ishmael
In: Toronto
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| Chad wrote: | | And is that also what accounted for the demise of our own aquatic predecessors? |
You mean you don't believe in mermaids?
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Chad
In: Ramsbottom
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| Ish wrote: - - You mean you don't believe in mermaids? |
Depends on my level of intoxication.
| Dan wrote: - - For humans, what about wading around in snow? |
You mean like polar bears and reindeer?
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Mick Harper
Site Admin
In: London
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| And is that also what accounted for the demise of our own aquatic predecessors? If so, when did all of this transpire - - or is that a secret just yet? |
Well, yes, it's still secret but the reason will be made clear in Volume II of An Introduction to PalaeoGeography: The End of Ice Ages, when I show how rapidly the sea changes in various ways.
But it will probably help me if everyone just dives in and tries to guess. That way, if I like your idea I can always say, "Yes, that's right! Well done!" This technique only works with people who have brilliant minds and trusting natures.
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Chad
In: Ramsbottom
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| ....it will probably help me if everyone just dives in..... |
Right then, here's my rather ungainly dive.
Once upon a time, several million years ago, in deepest darkest Africa, lived a species of ape -- the bonobo -- whose range was then, far greater than it is now. Following a sudden and dramatic change in the environment, the range of this ape was drastically reduced.
The residual population in Central Africa continued on to this day, pretty much unchanged. However, in the extreme north-east of its former territory, a second and very much smaller group survived in isolation, in a much changed and far wetter environment, in the horn of Africa.
This tiny population then did the sensible thing; it chose to rapidly evolve (in established Morganian fashion) into our aquatic ape ancestors. - - So successful did they become, that they went on to occupy the coastal waters all the way from the Red Sea, around the Indian Ocean and as far as .... well at least the East Asian coast.
At various times and locations along this journey, small groups would occasionally drag their sorry arses out of the water, to try their luck on dry land. - - The first of these were the australopithecines and later our hominid cousins would give it a go.
But back to our aquatic parents. - - Just as everything was looking rosy, they were virtually exterminated by a global catastrophe about seventy thousand years ago, which lead to a dramatic change in sea level and a 'once in a zillion years' size volcano in South-East Asia. - - Only a minute population survived, finding itself high and dry, somewhere in East Asia.
This tiny population then did the sensible thing; it chose to rapidly evolve -- into Modern Man. - - Once this new species had stabilized and established itself it went on to colonize the globe -- separate groups reaching Australia, the Middle East and Alaska at about the same time. - - The northern group, who initially colonized the Americas and Northern Asia - and eventually Europe, were the reindeer herding, oak cultivating, pigeon fanciers we all know and love.
(All times, locations, and principal characters are gross approximations)
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Mick Harper
Site Admin
In: London
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Yes, that's quite good.
| Following a sudden and dramatic change in the environment |
| ....a global catastrophe about seventy thousand years ago, |
I will be able to provide some stiffening to these otherwise somewhat 'with one bound they were free' interludes.
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Heard about the Tiktaalik?
http://en.wikipedia.org/wiki/Tiktaalik
It says in my National Geographic that:
In 2004, Neil Shubin of the University of Chicago and his colleagues found a 375-million-year-old fossil high in the Canadian Arctic - a creature that fit neatly in the gap between fish and land-living animals. They named it Tiktaalik. Although it was plainly a fish with scales and fins, Tiktaalik had a flat, amphibian-style head with a distinct neck, and bones inside its fins corresponding to the upper and lower arms bones and even the wrists of land animals.
The fossil's genes are lost in the mists of time. But, the researchers studied a living proxy - a primitive bony fish called a paddlefish - and found that the pattern of gene expression that builds the bones in its fins is much the same as the one that assembles the limb in the embryo of a bird, a mammal, or any other land-living animal. The difference is only that it is switched on for a shorter time in fish.
The discovery overturned a long-held notion that the acquisition of limbs required a radical evolutionary event. | |
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Chad
In: Ramsbottom
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| the pattern of gene expression that builds the bones in its fins is much the same as the one that assembles the limb in the embryo of a bird, a mammal, or any other land-living animal. The difference is only that it is switched on for a shorter time in fish. |
Mr. Fish: 'You know love, one of these days one of our kids is going to want to venture out onto dry land and when he does he's going to need limbs'.
Mrs. Fish: 'Yes dear, we'd better hurry up and develop some genes to enable him to grow some'.
Mr. Fish: 'Good idea love. But we'd best not leave them switched on too long just yet -- the bloody things would get in the way down here!'
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Ishmael
In: Toronto
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So a flipper or fin is merely an embryonic arm.
But then doesn't that sound like the arm came first?
If we gave some kind of thalidomide drug to Mrs. Whale, could her offspring grow legs?
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Chad
In: Ramsbottom
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| But then doesn't that sound like the arm came first? |
Sure does - - either that or some degree of conscious pre-planning.
But it will probably turn out that a large variety of mutant fins were tried, tested and rejected before just the right model came along.
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