Re: Becoming altricial/bi

Paul Crowley (Paul@crowleyp.demon.co.uk)
Tue, 10 Oct 95 20:04:12 GMT

In article <60.3218.7295.0N1F857F@canrem.com>
j#d#.moore@canrem.com "J. Moore" writes:

> Pa> <A lot of convoluted and obscurely worded prose - which is so
> Pa> uncharacteristic that extraneous reasons must be supposed>
>
> That would be the prose wherein I had to point out to you that a
> bipedal hominid infant would be expected to have bipedal parents.
> Such an obvious point, really, that I find it surprising that you
> had to have it pointed out to you. Still more surprising that you
> found this convoluted and obscure:
>
> JM> You seem to be insisting that I am out of line in pointing out that
> JM> a population of bipedal infants would be expected to have bipedal
> JM> parents.

You are out of line in wasting everyone's time. Why descend to empty
tautologies? Maybe you are trying to avoid the issues.

> JM> The mother of a bipedal child being herself bipedal is
> JM> hardly a great mental stretch. I suppose you don't want to talk
> JM> about it because it negates the problem of carrying an infant,
> JM> even if that infant didn't have good grasping abilities.

I don't like to waste time discussing tautologies. Certainly not when
you draw utterly nonsensical conclusions from them. As I have said so
often: a maternal chimp, with a six-month infant attached, can run,
climb, brachiate, fight, throw stones at leopards, sleep safely and
soundly all night. She can almost forget she has an infant. It could
almost as well be inside her since it suckles at will.

A bipedal maternal hominid with a six-month infant can do NONE of
these things. Ever tried climbing a tree, naked, with a naked six-
month infant? Sleeping all night in the tree with it? Running with
it. Throwing a stone while carrying it? Or wielding a club?

> Pa> Do you accept:
> Pa> b) that bipedalism, _on_its_own_, requires a degree of
> Pa> maternal care for the hominid infant which is quite different and far
> Pa> in excess of that needed by the pre-bipedal infant?
>
> Different? Insofar as the predominate mode of locomotion is
> different, and the infant would be initially carried in front of
> the mother rather than behind, yes. This would tend to promote early
> mother-child teaching-learning (and probably parental bonds) to a
> somewhat greater degree than seen in chimps.

I find it hard to believe that I am reading this. Who do you think
you are fooling?

> This early period,
> until walking began, would not at first be as long as seen among
> modern humans, however, because the longer infant development
> period didn't come up until about 2.5-2 mya.

How do you know this? The old time machine again? They got bigger
brains around then, but who's to say this needed longer infant
development? That thinking dates from the time, twenty years ago,
when everyone thought brain growth came first.

> So as to "far in
> excess", I would have to say no. There is no reason to think it
> would be appreciably in excess of what chimps go through; their
> young are quite dependent on their mothers until 5 years old.
> "Orphaned chimpanzees at Gombe or Mahale rarely survived if under
> five years of age at the time of the mother's death." (Caroline
> Tutin 1994:188, in *Chimpanzee Cultures*, Harvard U. Press).

Yes. Infants really depend on their mother's health, energy and
fitness. If you wanted to survive past 5, would you opt to be a
chimp or an early hominid (on your savanna/mosaic scenario)?

> Pa> c) that when bipedalism was first established the mother/infant
> Pa> pair could not have normally slept in the trees?
>
> Of course they could have. Hell, WE can do it,

You can normally sleep in the trees? Naked? Holding onto a naked six-
month infant? And looking after say a 2-year old and a 4-year old?
For twelve dark, bitterly cold, hours every night in the African
mosaic/savannah? Wow! Tell me how. Or quote me the reference.

> and they had feet
> that were demonstrably better adapted to grasping and climbing
> than ours. Alex has pointed this out to you several times.

Since fossil foot bones >3.5 mya are extremely rare, and of most
uncertain interpretation, this is pious hope. It's not science.

> Pa> d) that prior to the use of fire, hominids could not normally
> Pa> have slept on open ground? ^^^^^^^^
>
> Of course they could have. Chimps can do it; why couldn't early
> hominids?

Chimps have the good sense to *normally* sleep in trees. They will
only sleep on the ground when they feel it's safe - i.e. they know
the lions, leopards and hyenas, are away or not hungry. The word
was "normally".

> These things have been pointed out to you before. Continuing to
> bring them up as if they hadn't makes you look foolish.

Wow! No comment!

Paul.