Michael Vassar is having trouble accessing this site right now, so asked me to relay this question:
You mention in your book (p. 69) that from 100,000 BC to 12,000 BC, the human population increased from half a million to six million thanks to better hunting tools and techniques. On the other hand, from page 100 onwards, you discuss Malthusian limits to population, implying that the sizes of primitive populations were proportional to the amount of food available. In other words, you seem to be saying that from 100,000 BC to 12,000 BC, the human population grew because better hunting techniques increased the availability of food.
But better hunting technologies won’t generally tend to raise Malthusian limits strongly. While hunting better will mean that new prey become exploitable, it also means that old prey are continually hunted to extinction. The net result isn’t a systematic trend. How strong is the evidence for any prehistoric population sizes? How do the implied population densities compare to those for other large omnivores, such as black bears and pigs, in their territories, or to the population densities at which Chimps live? Why would human densities have been much lower?
Better hunting techniques can significantly raise Malthusian limits.
First, you have to remember that old-fashioned humans were one
predator among many: improved hunting techniques could raise our
share of the pot, as well as decreasing other predators’ tendency to
eat us. Also, modern humans seem to have used carcasses more
efficiently than Neanderthals: they had permafrost storage pits and
drying racks, so could have preserved meat for long periods. Neanderthals
didn’t, and I think they must have wasted a lot. Next, moderns used
snares, traps, nets, bows etc to catch smaller game not much harvested
by Neanderthals: they also made more use of fish and molluscs. And lastly,
more plant foods. Altogether, their innovations gave them a larger share of the game, used that share more efficiently, tapped marine resources (lots of
salmon in Europe), and harvested resources at a lower trophic level ( plants
for example), which are always more abundant.
Hunting to extinction happened in some places, but not everywhere: it hardly happened in Africa at all. It happened most in places with no previous hominid occupation.
Implied population densities are, I think, extrapolations from known hunter
gatherers, salted with some archeological info. Estimated densities range from 0.01/km sq to 1/km sq, strongly dependent upon resources. A lot like those of
bears. Lower than chimps, probably: but then chimps manage with a lower-quality diet than humans. We’re probably not as good at digesting leaves as they are.
Probably you have to consider Pleistocene climate as well: the world was generally nastier—colder, drier, lower plant productivity due to low CO2 levels.
Michael Vassar is having trouble accessing this site right now, so asked me to relay this question:
You mention in your book (p. 69) that from 100,000 BC to 12,000 BC, the human population increased from half a million to six million thanks to better hunting tools and techniques. On the other hand, from page 100 onwards, you discuss Malthusian limits to population, implying that the sizes of primitive populations were proportional to the amount of food available. In other words, you seem to be saying that from 100,000 BC to 12,000 BC, the human population grew because better hunting techniques increased the availability of food.
But better hunting technologies won’t generally tend to raise Malthusian limits strongly. While hunting better will mean that new prey become exploitable, it also means that old prey are continually hunted to extinction. The net result isn’t a systematic trend. How strong is the evidence for any prehistoric population sizes? How do the implied population densities compare to those for other large omnivores, such as black bears and pigs, in their territories, or to the population densities at which Chimps live? Why would human densities have been much lower?
First, you have to remember that old-fashioned humans were one predator among many: improved hunting techniques could raise our share of the pot, as well as decreasing other predators’ tendency to eat us. Also, modern humans seem to have used carcasses more efficiently than Neanderthals: they had permafrost storage pits and drying racks, so could have preserved meat for long periods. Neanderthals didn’t, and I think they must have wasted a lot. Next, moderns used snares, traps, nets, bows etc to catch smaller game not much harvested by Neanderthals: they also made more use of fish and molluscs. And lastly, more plant foods. Altogether, their innovations gave them a larger share of the game, used that share more efficiently, tapped marine resources (lots of salmon in Europe), and harvested resources at a lower trophic level ( plants for example), which are always more abundant.
Hunting to extinction happened in some places, but not everywhere: it hardly happened in Africa at all. It happened most in places with no previous hominid occupation.
Implied population densities are, I think, extrapolations from known hunter gatherers, salted with some archeological info. Estimated densities range from 0.01/km sq to 1/km sq, strongly dependent upon resources. A lot like those of bears. Lower than chimps, probably: but then chimps manage with a lower-quality diet than humans. We’re probably not as good at digesting leaves as they are.
Probably you have to consider Pleistocene climate as well: the world was generally nastier—colder, drier, lower plant productivity due to low CO2 levels.