Re: What were the habitats of early hominids?

On Aug 2, 2:23 pm, claudiusd...@xxxxxxxxxxxxx wrote:
I think it's pointless to talk of hybridization since we have no
evidence and hybridization doesn't explain anything. It's an
unncessary diverssion from what really matter about hominid evolution:
the selective origins of our communal adaptations.
There is no "moment" of conception, but a period of time during which
the
ovum wall is permeable. We know further that a myriad of sperm must be
present to deliver enough enzyme to create permeability.

Sometimes more than one sperm gets in. If both are XX or XY, no
biggie,
nobody notices. but if not, then the resulting fertilization is XXY;
which is to
say, a hermaphrodite. Its a lot more common than Christian culture
likes
to admit. I have met two, in different states at different times. If
you have
contacts within the gay community, you may find some. They feel much
more accepted there.

But now, from "Sperm Wars" we find that not all the sperm present at a
conception need be from the same donor. And we find further that DNA
does not zip together like a new jacket, but like an old one, that
often has
loops hung out. That can be matched with snippets off the Y chromosome
even if the number of chromosomes dont match.

You only have one mother, but you may have more than one 'father'.

Now, there are certain problems with the conventional out of Africa
theory
that this solves. Then too, there are problems with a genetic bottle
neck
like the mt Tuba event. If there were only 10,000 hominids alive, they
all
had to be living in much larger, but isolated groups in order to
prevent the
notorious problems of inbreeding. With a species as complicated as the
hominids, the freak rate would've went thru the roof.

But not with hybridization going on. There's no reason to think that
females
back then were not gang raped and kidnapped by divergent, and now
extinct
hominid lines. But survived with their progeny anyway, With snippets
of new
Y chromosomes that would have affected the inbreeding problem.

Presumably, some females would've already been pregnant with taken,
and
the progeny that gets born accepted into the group as 'native'. I know
some
pretty ugly bitches that manage to stay pregnant now, so I dont expect
it
wouldda been different back then.

And this would have had an even more powerful effect when hominids are
driven out and then stumble into new ecosystems. I know the usual
image is
the alpha male pioneer finding new lands. But history shows us its the
alpha
male warriors who get to keep the old lands, and its the refugees who
find the
new opportunities.

But between the effects of new ecosystems, and the hybridization with
other
lines, I dont think we'll ever be able to sort out the descent of man.
Then too,
in Chad for instance, we have *one* skull. No way of knowing if what
we have
is at all representive. Likewise the debate about the boy that was
found in the
mud. No way of knowing if he was there to get a drink, or if that was
part of
his daily foraging routine. Be nice to have a more detailed report on
his teeth
to sort out more clues about his diet.

I can see how a series of dry years, needing to subsist on tubers
rather than
fruit, or perhaps driven out of areas that had fruit, the tooth wear
could have
been bad enuf to result in caries, and then abscesses at a young age,
most
especially if the adaptation of thicker dentine had not yet begun.

I'm not as clear as I hope to be, but I only meant the other primates
had much
more limited diets than the hominids. Everything has a more limited
diet than
the hominids. Brain development would have facilitated the
exploitation of new
food sources. The more new food sources the hominids found the smarter
they
had to be to deal with the diversity, the smarter they got, the more
new food
sources they found...

Likewise, hominids bred dogs to help cope with new food sources, and
the array
of instincts the canines have, in addition to their physical form, is
really quite
remarkable over the course of the last 15,000 years, as well as the
complexity
of canine responses to particular situations. i would add, that some
hominids
are much more adept at understanding the body language of dogs, and
able
to benefit far more from the interaction, whereas other genetic lines
tend to
regard canines with fear much more often.

.

Relevant Pages

  • Re: What were the habitats of early hominids?
    ... Sometimes more than one sperm gets in. ... hominids, the freak rate would've went thru the roof. ... you don't have a hypothesis that involves natural selection. ... The more new food sources the hominids found the smarter ...
    (sci.anthropology.paleo)
  • Re: Bipedalism in different substrates
    ... we can be pretty sure of the forests and terrestrial food sources ... >>those are in fact the food sources all of our cousins exploit. ... > that was available to early hominids in Africa I have no idea. ... plus a fair bit of meat. ...
    (sci.anthropology.paleo)