"Marc Verhaegen"  wrote in
news:bu7blb$1r1v$1{at}darwin.ediacara.org: 

> 
> "William Morse"  wrote in message
> news:bu3s7l$oeu$1{at}darwin.ediacara.org...
> 
>> > The essence is this: you are incapable of explaining why humans &
>> > chimps 
> differ. A coastal past in our history (probably end-Plio-,
> begin-Pleistocene, for some time) nicely explains a lot of these
> differences. Alister Hardy in his paper "Was Man more aquatic in the
> past?" (NS 1960) described how a sea-side life - beach-combing,
> wading, swimming, collecting coconuts, fruits, shellfish, turtles &
> turtle eggs, bird eggs, crabs, seaweeds etc. - explains many human
> traits (absent in our nearest relatives the chimps) a lot better than
> dry savanna scenarios do: very large brain (but reduced olfactory bulb
> - totally unexpected in the savanna), excellent breath-hold control
> (up to minutes), greater diving skills, well-developed vocality,
> extreme handiness & tool use, reduction of climbing skills, reduction
> of fur, more subcutaneous fat, very long legs, more linear body build,
> high needs of iodine, sodium & poly-unsaturated fatty acids etc. 
> 
>> One of the basic problems, as J. Moore pointed out, is that we are
>> not in 
> fact particularly well adapted to a fully aquatic existence.
> 
> Who speaks about fully aquatic?? Seaside. Hardy: "more aquatic."

As noted in my previous follow, I can agree with seaside - but that then 
falls far short of explaining the wide range of features that AAT 
purports to explain. 


(snip stuff on fully aquatic existence) 


>> We are so poorly adapted to truly deep diving that the well-developed
> vocality is unlikely to be due to the development of conscious
> breathing control
> 
> 1) I didn't say that, see the scenario above. There's no doubt IMO
> vocality as in gibbons played an important role in the development of
> human vocality. Otters (waterside) are more vocalic that weasels.
> Arboreal mammals are usu. more vocalic than related species in more
> open milieus. Savanna mammals generally have less variation in
> vocality. 
> 
>>, as it may be in birds and truly aquatic mammals. It is more likely
>>that 
> the breath-hold control is a byproduct of speech.
 
> Then you can't explain speech. You can't explain why human can speak &
> why chimps couldn't evolve this skill.

Chimps (or rather a very near relative) _did_ evolve this skill. We are 
the result. Read "The Symbolic Species" for an excellent discussion of 
this topic. 

 
> Having said the above, a quick look at real estate prices for
>> waterfront 
> property makes a convincing case without any other evidence that we
> are adapted to life _near_ the water. Given our relatively high
> behavioral plasticity, even a relatively recent (0.8 ma would qualify
> as recent in my book) period of development primarily in a coastal
> setting might well make sense in explaining our love for water.
> However this will not account for bipedalism
 
> Evolved gradually: first (hominoid) wading-climbing in swamp forests
> (short legged bent-knees-bent-hips-bipedality, still partial
> suspensory), later (seaside early Homo) loss of climbing & evolution
> of straight body (for streamlining, regular swimming), still later
> (sapiens LCA) exclusively walking.

I don't buy this, maybe partly because I don't like swamps, but it is at 
least an interesting possibility for explaining the development of 
bipedality in humans (at least until you get to the straight body part 
which is hogwash since we are relatively bad at swimming). 


 
>>, hairlessness (have you looked at otters and seals?
 
> These species are not tropical. The very large male elephant seals &
> Steller sealions & walruses are furless in cold environments, but
> other pinnipeds & also sea otters are too small to be hairless. A
> tropical middle-sized semi-aquatic is the baburusa: furless.

Sea lions (250 lb) too small to be hairless? How about the Hawaiian monk 
seal - it is tropical. And the capybara is a tropical middle-sized semi-
aquatic, and it has lots of hair. Meanwhile elephants and rhinoceroses 
are non-aquatic but hairless. The point is that an aquatic existence does 
not necessarily lead to hairlessness, nor is hairlessness evidence for an 
aquatic existence. 
 
>> ), brain size, control, long legs, vocality, or tool use.
> 
> All not unexpected at the seaside (cf. tool using sea otters, long
> legs for wading, etc.)

And how about those tool using seals, as opposed to the chimps that are 
incapable of tool use. And how about those wading giraffes, not to 
mention all those other mammals that have adopted bipedalism as a result 
of their semi-aquatic existence - the babirusa, capybara, otters, water 
buffalo, beaver ... oh darn, _none_ of them are bipedal.  


As I said previously, humans show evidence of development in a shoreline 
habitat - but it only explains a few of the differences that set us apart 
from our nearest relatives.


Yours,

Bill Morse
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