Women are weaker. . .

[Jingo]

The cite page I provided did look a little sloppy, but I think the top of the page was mis-coded—the main body of the text and the biblio should be intact—just scroll down until I find a better link.

Collounsbury said:

European late pleistocene? Are we limiting ourselves to Europe?

It is a bit limiting, granted. I thought that for purposes of this discussion, I’d limit the focus as much as possible to avoid generalizations. Of course, extrapolating only these data poses another debate…something I was trying to avoid. I’m reasonably confident that this area (temporal and geographic) should suffice to answer the OP. Also, I have studied non-human primate paleontology from this era, and am thus comfortable with paleo-anthroplogy in the European pleistocene as well.

Lemur866 said:

Again, assumes that we hunted dangerous animals. Look, if hunting is incredibly dangerous, then the proto-humans that tried it would be extinct. I agree that killing a mammoth is dangerous, killing a buffalo is dangerous. Killing a lizard is not dangerous. It is true that our ancestors were in danger from predators, but they were in danger of predators while gathering as well. You aren’t in more danger while killing a lizard than you are while picking berries.

I understand your point to be that human hunting had nothing to do with sexually dimorphic evolution. Perhaps it didn’t have much influence—I concur—but it’s reasonable to think that it did have some. Please refer to the bibliography presented to learn of early hominid diet. Humans were hunter-gatherers right up until about 12,000 years ago. (And I’m being very generous, here) The animals primarily hunted were large herd animals. The best reason put forth for this is that the bigger the animal, the bigger the payoff in calories and incidental animal by-products (fur, teeth, bones etc. to be used as tools or clothing). Hunting was not ‘incredibly’ dangerous—but dangerous enough, just the same. The amount of energy required to catch and prepare a lizard, rabbit, mouse, squirrel, snake or other small critter is very close to the caloric benefit of that animal. A big buffalo, caribou or mastodon is much more attractive a target: easy to find, easy to track, big payoff in calories…but occasionally kills your friend Og. I understand arguments that this was not the most efficient way of life for our early hominid ancestors, but the fact remains that it’s how they lived. Remember they were early ancestors…they just followed the game herds and if they came across some tasty plants, they ate ‘em and moved on.

Roughly 15,000 years ago, groups of humans crossed the Bering land/ice bridge into the Americas…and they weren’t following lizards.

Again, I think that intra-species competition was the primary actor in sexually dimorphic evolution in humans. But it remains possible that somewhere in our long history as hunter-gatherers, we had a few traits selected as a result of our hunting culture.

[Gaspode]

***Originally posted by Lemur866 * Sure, but Eskimos are not typical of our early hominid ancestors. So our ancestors probably hunted more than chimps. But they didn’t hunt mammoths, they hunted lizards, baby birds, termites, and rodents.

**
I was just nitpicking about the Eskimos. As I said I have seen no evidence concerning the dietary habits of our ancestors, but certain I’m at some stage the ancestors of modern humans had to have hunted large game, simply because we do today. Even chimpanzees regularly hunt quite large monkeys, and baboons will hunt gazelle so I can’t imagine humans not doing the same.

This assumes that we hunted dangerous animals. I strongly doubt this. We hunted animals that were not dangerous. Big-game hunting is only possible with advanced technology, like bows and arrows.

I agree 100% about big game hunting that’s exactly what I’ve been arguing, but there is always a risk benefit level in the hunting choices of any species.

But this already assumes that the females are “yours”. How did they get that way? How do you control their movements? How do you stop the other males from kicking you out and taking “your” females? By fighting, or the threat of fighting.

As I explained when I originally posted this, it was by fighting and by the combination of the resources of a group of related males. I think there’s common agreement her that some sexual dimorphism was inherited from our more primitive ancestors and probably a harem structure.

Look, if hunting is incredibly dangerous, then the proto-humans that tried it would be extinct

I can’t see why they would be extinct, I think the weaker males would be extinct leading to an increase in males size. Hunting is dangerous for lions, mongoose and wolverines, but they do it. No one said that hunting is incredibly dangerous, simply that it is inherently dangerous. Even a rat can inflict a fatal bite. I for one have been arguing against early humans hunting large game without effective weapons.

The males provide almost no food.

True, but they still provide care.

The males provide protection because they are larger. But they are not larger because they must provide protection.

Surely if something provides a benefit then it is likely to be selected for. If even bigger males are even better at providing protection then wouldn’t they would be more successful at reproducing? I’m willing to accept that the beginning of dimorphism weer inherited from our ancestors. Added to this the current opinion seems to be that the reason why lions are so large and useless is simply because they do need to fight hyenas, not because they need to fight other males. This degree of dimorphism is found in no other cat species, and almost all fight for mates.

Our proto-human male ancestors may have hunted more than the females, but only because they didn’t have to take care of the kids like the females did.

Isn’t this just another way of saying “While rearing young, early hominid females were unable to hunt large game animals as efficiently as males. The males were therefore encouraged to undertake the inherently perilous task of hunting, while the females both reared the offspring and gathered less belligerent foodstuffs” ?

male lions do not invest a lot in parental care. They are primarily guarding against males of their species

Apparently not true, see above

A harem is a female social structure…the females stay together and cooperate. A male attaches himself to the harem, kicks out any adolescent males, and mates with any new adolescent females. At some point, another male from outside takes over. But the females continue their social network for most of their lives.**

Even if this were true, what difference does it make to a male’s ability to hunt making him more likely to hold the harem for longer. It isn’t entirely true. In primates and lions the support of the females is essential in a male holding the harem. They must be willing to select him as their mate. Added to this in chimpanzee and gorilla society the non-dominant males continue to live with group.

[Lemur866]

*Originally posted by Jingo *
Please refer to the bibliography presented to learn of early hominid diet. Humans were hunter-gatherers right up until about 12,000 years ago. (And I’m being very generous, here) The animals primarily hunted were large herd animals. The best reason put forth for this is that the bigger the animal, the bigger the payoff in calories and incidental animal by-products (fur, teeth, bones etc. to be used as tools or clothing).

I know that anatomically modern humans were often big game hunters. But there is no evidence that our earlier ancestors…I’m talking about australopithecus grade here…were big game hunters, in fact it is obvious that they were not. But when we reach anatomically modern humans, they are anatomically modern, with our current sexual dimorphism. So it is logically impossible for sexual dimorphism to have evolved for big game hunting, since by the time humans were hunting big game they were anatomically modern.

And anyway, suppose that big game hunting requires large, robust, strong humans. Well, why wouldn’t the females evolve to be just as large, robust, and strong as the males? There is nothing intrinic about hunting that requires maleness. Female carnivora have no trouble hunting, there is no evidence that male carnivora are more successful hunters than females. So, if humans needed to be robust to hunt, ALL humans would become robust. But this is irrelevant, since humans were sexual dimorphic before they hunted. Gorillas are sexually dimorphic, and never hunt. Orangutans are sexually dimorphic, and never hunt. Chimpanzees are sexually dimorphic and almost never hunt. Our australopithecine grade ancestors were sexually dimorphic (see Johansen’s “First Family”), yet we are certain that they were not big-game hunters even if we don’t know the exact proportion of scavenged meat, small game meat, and gathering they did.

Remember they were early ancestors…they just followed the game herds and if they came across some tasty plants, they ate ‘em and moved on.

Roughly 15,000 years ago, groups of humans crossed the Bering land/ice bridge into the Americas…and they weren’t following lizards.

I guess we are using different definitions of “early”. Since we are talking about the evolution of the human body, “early” MUST mean “before anatomically modern humans”. And since anatomically modern humans are ~100,000 years old or so, “early” has to be before then. We are talking millions of years ago, not thousands.

And it’s not even true that “modern early” people wandered around following the game herds. Almost all hunter gatherers have some sort of home territory, even those guys who wandered over the bering straits. They were looking for a new place to live. Now, they might have moved after several years in the same place, but they had homes, just like all other human cultures do.

[system]

*Originally posted by Jingo *
The cite page I provided did look a little sloppy, but I think the top of the page was mis-coded—the main body of the text and the biblio should be intact—just scroll down until I find a better link.

biblio was intact but the rest was/is gobblygook. No problems, nice biblio.

Collounsbury said:

European late pleistocene? Are we limiting ourselves to Europe?

It is a bit limiting, granted. I thought that for purposes of this discussion, I’d limit the focus as much as possible to avoid generalizations. Of course, extrapolating only these data poses another debate…something I was trying to avoid. I’m reasonably confident that this area (temporal and geographic) should suffice to answer the OP. Also, I have studied non-human primate paleontology from this era, and am thus comfortable with paleo-anthroplogy in the European pleistocene as well.

No problems, its just my instinct is that its not the right place to argue from: almost everything important, evolutionarily speaking for homo sap, is going on in Africa. Not disagreeing per se with any conclusions, but offering a note of caution that for the greater time=span relevent to the Q the European plesitocene is not typical.

The animals primarily hunted were large herd animals. The best reason put forth for this is that the bigger the animal, the bigger the payoff in calories and incidental animal by-products (fur, teeth, bones etc. to be used as tools or clothing). Hunting was not ‘incredibly’ dangerous—but dangerous enough, just the same. The amount of energy required to catch and prepare a lizard, rabbit, mouse, squirrel, snake or other small critter is very close to the caloric benefit of that animal. A big buffalo, caribou or mastodon is much more attractive a target: easy to find, easy to track, big payoff in calories…but occasionally kills your friend Og. I understand arguments that this was not the most efficient way of life for our early hominid ancestors, but the fact remains that it’s how they lived. Remember they were early ancestors…they just followed the game herds and if they came across some tasty plants, they ate ‘em and moved on.

I think the problem here is your time frame is well after what dimorphism there is already well-developed so its explanatory value per se is diluted.

Again, I think that intra-species competition was the primary actor in sexually dimorphic evolution in humans. But it remains possible that somewhere in our long history as hunter-gatherers, we had a few traits selected as a result of our hunting culture.

That seem fair.