Re: Adaptive Niche of Arc

Norman Sides (
22 Jun 1995 21:59:34 -0700

Sheez! I did it again! Well, if this posting gets through, Jim, your
entire article will be there for context.

Jim, I'm going to address issues here that you raised in your post of
June 18. I'll respond to your post of the 19th if I'm able (your double
posting having been due to some previous technical problems on my part.
BTW, although I feel sympathy in regard to the problems you described
with user unfriendly software, it's cheering to know that even those
with some experience may still ocassionally get bitten. :-)

>Na> How could natural selection favor abilities and behavioral
>Na> dispositions enabling people to create social systems of a complexity
>Na> and diversity far greater than any that their G&H ancestors needed to
>Na> cope with conditions they actually encountered? Why didn't evolution
>Na> just maintain the G&H status-quo? Or why didn't it simply produce some
>Na> more effective type of G&Hers?
>Well, this is in fact what seems to have been going on *throughout* human
>evolution, from early australopithecines to H.s.s.: producing hominids
>that are better at what they do than their ancestors were, and who do a
>better job of making an environment that works for them out of what they
>have available, making more different niches, particularly areas with
>vastly different climate, available for their use.

Certainly it's true that their bipedal adaptation (and their probable tool
use) enabled early hominids to survive in more open habitats than could
their forest dwelling ancestors, but I think anyone would be hard pressed
to produce evidence that they created cultures of far greater complexity
and variety than they needed to cope with conditions they actually
encountered. They probably created more complex proto-cultures than do
Japanese macaques, but I was under the impression that the robust
australopithecines seem to have been eating a lot of course vegetable
matter; that they were primarily root grubbers or foragers somewhat
comparable to gorillas but in drier and more open habitat. If this is the
case they would seem to have occupied a fairly narrow and specialized
adaptive niche. This would be consistent with the emergence of different
robust species in the various occupied regions. Local differentiation
occurred but it was primarily biological. I don't think much can be said
about australopithecine culture because they just didn't leave much

>Na> I do think, however, that a considerable
>Na> body of evidence supports the idea that they were restricted to a
>Na> particular adaptive niche (or a cluster of related niches?).
>Depends on how you define that. What could be said to be the "odd
>difference" about hominids is that long before the modern types, like
>H.s.s or even archaic H.s. and Neadertals, they had been making their
>G&H niche work in ever wider climatic conditions, which is a pretty
>remarkable thing really. We need to remember that hominids, like all
>organisms, *make their own environment*. (Plants, as one example, break
>up the soil they're in with their roots, which lets water in.) Richard
>Lewontin points out that all organisms create their environment out of
>what's around them in their reactions to what's useful, what they
>perceive or don't perceive (he points out, for instance, that gravity is
>completely unimportant to many organisms, even though for us it's a
>critically important and ubiquitous force), and so on. There are
>limits for each organism as to how far they can take this without
>gross physical change (which may or may not be forthcoming) that is
>larger than the amount of somatic change they can undergo. ("Fish gotta
>swim, birds gotta fly", although even those generalities have to be
>modified to fit the real world [much as the next line in the song has to
>be modified to fit the relaities of human sexuality ;)].) Physical
>change to fit local conditions limits options, and that's where hominids
>got lucky.

I have to admit that I'm not familiar with all the paleontological data,
but it's my impression (and I may well be mistaken) that H. habilus
wasn't really all that unusual in terms of occupying a very broad range
of habitats. Apparently they were eating a wide variety of foods and, as
you say, meat comprised a larger percentage of the diet. If I were to
take a stab at defining their niche, I would say that, like baboons
and raccoons, they were intelligent and behaviorally flexible
opportunists, that scavenging provided much of their meat, and that
foraging techniques were fairly consistent over their entire range. Like
most omnivores, they could utilize a wide variety of habitat resources
without specializing in any particular highly developed foraging
strategy. As with many other social species, social transmission of behavior
would have enabled the young to acquire proven survival skills. But is
there any evidence that cultural differentiation enabled them to become
more widely distributed or to cope with widely divergent habitat
conditions? Opportunistic raccoons and Virginia opossums have migrated
into new regions, but without significantly modifying their basic foraging
techniques (raids on garbage cans are just a variation on "traditional"
raccoon methods). H. habilus gained a literal and a figurative "edge"
from their crude stone tools, but don't seem to have been great innovators.

>Hominids, apparently uniquely among primates, happened to get around
>this through a set of "lucky breaks". Through the use of some improved
>tools, more steady and increased use of meat sources, increased stature,
>brain size, and possibly/probably such inventions as slings or other
>primitive containers and carriers, as well as ongoing innovations in
>social organization and communication, they became able, between 2 and
>1.5 million years ago, to use more climatically different areas, which
>dissolved barriers to travel and opened up to them one whole helluva lot
>of space.
>So I'd say your next statement is probably not completely accurate:
>Na> In this they were like all the creatures before them. It's the
>Na> moderns, not the archaics, who are anomolous in this respect.
>There are certainly other types of animals who cover this sort of
>ground, although generally, in mammals, with bodily changes (greater
>than somatic) that are greater than what we seem to see in erectus et
>al. These would be the various dogs, in which we have different species
>along the equator than we have in the temperate forests, although they
>seem to have a great deal of interbreeding ability among many of these
>types; horses (horses, zebras); pigs; etc. But hominids *are* odd among
>primates in this, and this started so long ago. Can we really say that
>this change, from say australopithecine to late erectus, is less of a
>dramatic change than from erectus to H.s.s.?

The change from australopithecine to late erectus undoubtedly involved an
unprecedented degree of genetic-cultural coevolution. It was dramatic.
But, as with dogs, there may have been different species. I noticed in
another thread that Harry Erwin has posted a list of (speciational?)
branchings in Homo, with references to the racially subdivided Eastern
erectus branch, the East/South African group and the North African group
that grades into archaic sapiens populations in various regions. I notice
also that he classed Neandertals as Homo neanderthalensis rather than as
Homo sapiens neanderthalensis. We have used the latter terminology in
this discussion, but personally I never did fully buy the idea that H.
neanderthalensis and H. sapiens should be grouped together as
conspecific. Just an opinion, but what's the consensus these days? Are
Neandertals being regarded again as speciationally distinct? At any rate
the explosive expansion of modern H. sapiens from the North African
group, with the rapid replacement of all archaic populations, seems to
point to some overwhelming adaptive advantage (once again I'm referring
to cultural "adaptations" here, but I think these are based on a
biological difference that enabled moderns to create locally
differentiated cultures).

>I think you could make a case either way because the two cases can't
>really be compared. They're both pretty dramatic. It's much the same
>reason you always see people thinking their era is the fastest changing
I think you could make a case either way because the two cases can't
>really be compared. They're both pretty dramatic. It's much the same
>reason you always see people thinking their era is the fastest changing
>ever -- it's because they didn't live in the previous eras. The changes
>we see now, are they really so much greater or faster than the
>changes in our ancestors' world views when they realized they *weren't*
>at the center of the universe? Than the introduction to Europe of the
>seed drill, which overnight meant you needed to keep one third as much
>of your harvest to plant your next year's crop, therefore trebling your
>yield with one little gadget? I'd say that would be a tough call. ;-)

I would agree that great changes have occurred in the historic past, and
during prehistory as well. Part of my argument is that modern humans are
inherently equipped to change lifestyles, to create new ways of life, to
deal with social and cultural change: and that these abilities have a
biological basis connected with the adaptive strategy of paleolithic
moderns. Our paleolithic ancestors were able to create new
ways of life incorporating locally differentiated and specialized
ecologies. This ability to "switch niches" was what enabled some groups,
in favored localities, to "invent" civilization. Even now, in an age
beset with deep and pervasive change, we are making use of abilites and
behavioral dispositions that would have been of high survival value to
paleolithic peoples trying to cope with new habitats or climatic changes.
That's just an opinion, but the idea has some explanatory power.

>Na> We have no evidence that archaics
>Na> produced representational art,but plenty of evidence from Australia,
>Na> Africa, Europe and the Americas that at least some paleolithic moderns
>Na> did so. Not every individual member of species Homo sapiens sapiens is
>Na> an artist or musician, but *every* society of modern humans produces
>Na> artistic and musical traditions (though these traditions can vary
>Na> greatly from group to another). The fact that archaics apparently did
>Na> not create art means that their cultures, and at least some aspects of
>Na> their thoughts and motivations differed in basic ways form those of
>Na> peoples living now.

>Could well be, although the devil in me has to ask "what is art?" and
>"how long does early art last?" Suppose we have some early weaving, one
>of those things that could well be produced by erectus and not survive,
>and you weave together a couple of different colors. Is that not art?
>Should we reasonably expect, say, a woven bark mat to survive a half a
>million years? Just a thought.

Perhaps archaics had artistic abilities. Some hand-axes are beautifully
crafted. I wonder, though, about the compositional ability that enables
an artist to create a painting that presents a single unified and
coherent effect. Everything in the painting: the color, the form and the
subject matter works together to create this effect. A society, and
especially a small, stable and culturally homogeneous society presents
somewhat this same unified aspect, as though it were somehow a communal
and trans-generational work of art. If the adaptive strategy of modern
humans involves the creation of ways of life, then some kind of
"compositional faculty" might be of adaptive value. Again, just a thought.:-)

As for the survival of archaic art, maybe no mats would have survived,
but I can't help feeling that, if archaics were very much like moderns,
some Neandertal teenager, on some protected cave wall somewhere, would
have scrawled some graffiti. ;-)

>One more quibble, one which I think gets lost very often, and which I
>think is important. We (that's the "we" of H.s.s) *didn't* abandon
>G&H. We don't abandon these things, we add to them. So "we" still
>gather, hunt, trap, farm, and manufacture. And in fact that "we" is
>closer to home than you might realize -- for instance, many spices, some
of which you probably have in your kitchen, are still gathered from
forests, not farmed.

I agree. "We," H.s.s., do all sorts of specialized things. We're not
inherently constrained to acquire predetermined sets of skills or adaptive
techniques. It's all the same as far as our adaptive strategy goes:
gatherer-hunters, mill workers, farmers or Phd's. BTW, I'll bet there
weren't any archaics out gathering spices in a forest to provide for an
international market. Only modern H. sapiens could come up with anything
as goofy as that. :-)

>Jim Moore (

* Q-Blue 2.0 *

Norman Sides (