Re: Oops, Back to the You Know What



Algis Kuliukas wrote:
> JAE wrote:
> > Algis Kuliukas wrote:
> > > JAE wrote:
> > > > Algis Kuliukas wrote:
> > > >
> > > > [snip]
> > > >
> > > > > So chimps and bonobos and orang utans and gibbons all had selective
> > > > > pressure from *not swimming* but humans carried on as if nothing had
> > > > > happenned. I see.
> > > >
> > > >
> > > > You do not see. You are confusing the absence of selection for the
> > > > retention of something with selection to eliminate something.
> > >
> > > Ok, so let me rephrase it: So chimps and bonobos and orang utans and
> > > gibbons all had absence of selective pressure *for* swimming but humans
> > > carried on as if nothing had happenned. Is that it? A bit
> > > unparsimonious, isn't it? Isn't it rather more likely that it was four
> > > ape species that carried on as if nothing had happenned and it was the
> > > hominin line that became, just slightly, more aquatic. But then I
> > > forgot: the principles of parsimony don't apply when the AAH is
> > > involved.
> >
> > There is nothing at all unparsiomonious about this. You do not seem to
> > have the best grasp of what the term parsimony means.
>
> What!? If today groups Bo, Ch, Gi, Or are non-swimmers and groups Hu
> and Go are swimmers, how can it be more parsimonious to explain that
> the LCA was a swimmer? If the LCA was a swimmer four changes are
> required. If the LCA was a non-swimmer two changes are required. I
> thought the use of parsimony in cladistics always attempts to contruct
> the tree which requires the fewest changes so tell me, Master, where is
> my understanding of parsimony lacking?

Cut the sarcastic 'master' crap. You're simply using it as a
smokescreen, unless you're simply trying to act like an *** for
effect. But since you asked, you are confusing "can swim" with "does
swim." This is a significant error. You should have paid more
attention. Swimming is not part of the ecological adaptation of apes
in general. Housecats do not swim. Housecats can swim.

You are using parsimony innaccurately when you equate "don't swim" with
"can't swim" when you don't have the evidence to back the claim.


> As swimming/non-swimming is not binary, surely the most parsimonious
> explanation of all is that the LCA was a slightly worse swimmer than,
> say, the gorilla. From that point gorillas have changed the least but
> the four non-swimming apes would have had to change relatively little
> too. Of all the apes, the human condition (the best swimmers of all the
> primates) is therefore the most remarkable and in need of an
> explanation - an AAH-based explanation, of course.
>
> > It is also rather unclear that the four ape species don't have an
> > ability to swim.
>
> Of course 'ability to swim' is not a binary character like the presence
> or absence of a particular bobble on the skull might be.
>
> > There are conflicting sources saying chimps can and cannot swim,
>
> One source (only one AFAIK) says "at least one" male chimp has been
> observed swimming - but it was only a few metres at most and it could
> have been falling whilst wading. Do you know of any other source? You
> seem to be alluding to that.... "source*s*".

This is really not difficult.


A single source that indicates that it is not impossible for a chimp to
swim indicates that the claim that it is impossible is false. The many
claims that they *can't* seem to be indicating more that they *don't*
swim.

I've said that there's a problem with the data.

Take a look at:

http://www.straightdope.com/mailbag/mcamelswim.html

This is, btw, a second source indicating that chimps can swim based on
actual eyewitness account. Note how it says also that gorillas *can't*
swim, something that, should your source on swimming gorillas be true,
is false. Who knows what he based it on. I suspect that the claims of
*inability* to swim in chimps are similarly basing this on nothing.
Moats will stop a creature that really doesn't want to swim even if the
*ability* is there.

> All other sources AFAIK say they cannot or do not swim. The fact that
> moats have been used in chimp enclosures in zoos for years and that
> several have drowned in them argues they generally cannot.

Note the difference between cannot and do not. These are very
different things and have drastic implications to the reconstruction of
character states based on a parsimonious cladistic relationship.

> > that gorillas can and cannot swim (one such source saying
> > they cannot said that while gorillas can't that chimps can),
>
> Which source is that please?

http://www.straightdope.com/mailbag/mcamelswim.html


> > that gibbons can and cannot swim.
>
> I've not read anything to suggest that gibbons can swim. The anecdotal
> evidence I've heard is that they drown very easily.

"http://animaldiversity.ummz.umich.edu/site/accounts/information/Hylobates_hoolock.html";

"Hoolock gibbons are known to swim well, but rarely do so and will go
out of their way to avoid water (Roonwal and Mohnot, 1977)." I haven't
checked out the primary reference. I do not vouch for it, though I did
not notice primary references supporting the claims that gibbons cannot
swim.

> > I've not seen any claims that orangs can swim but I've seen conflicting
> > reports saying that they're dreadfully
> > afraid of water and others saying they'll wade in regularly.
>
> I asked Birute Galdikas face to face about this a few weeks ago and she
> told me that in her experience orangs cannot swim but they are very
> comfortable wading.
>
> > What this
> > seems to indicate is that there's a dearth of real data out there, but
> > at least anecdotally, the's reason to believe that *inability to swim*
> > is somehow a heritable ancestral state for apes.
>
> So, are you agreeing with me then, or what?

Typo. There's a dearth of data. I am suspicious of the many claims
that apes CANNOT swim since the reports that they can seem to be from
positive evidence and the reports that they can't seem more based on
the fact that they don't swim.

> > Since the ability to
> > swim is widespread (not the ready desire, but the ability as the two
> > are different things) it's not remarkable that any mammal in particular
> > can swim *UNLESS* it's somehow clear that their ancestors could not.
>
> But as you've just admitted that the apes' "*inability to swim* is
> somehow a heritable ancestral state for apes" then presumably you must
> agree that the human ability to swim is remarkable.

A typo. No, I don't consider the *ability* remarkable. It's not
remarkable because it's not clear that our ancestors couldn't and it's
clear that mammals, in general, can. The remarkable thing is that at
some point, humans seemed to add aquatic resources to their diet in
ways that other creatures haven't. This is an interesting question for
human behavioral ecology. How did this happen? Was it purely a
technological advent? What I object to is the immediate assumption
that this accompanied a phenotypic change. Concluding that this
acompanied phenotypic changes is not currently warranted.

[snip]

> This aversion to making the painfully simple concession that, ok, water
> influenced our evolution more than it did the apes - is as astonishing
> as it is illustrative of a denial of the first principle of science -
> start with a simple observation and take it from there. You do not, can
> not, *dare* not make that first observation because if you did, you'd
> have to admit that the years of hostility against the AAH have been
> nothing but a grotesque facade.

[Back to the persecuted-Algis-hypothesis. Yawn]

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