Socialism in ant colonies and its lack in human societies: E.O. Wilson's perspectives

I recently chanced upon an old, 1997 interview of the famous biologist Edward Wilson. Wilson is known for his work on ant societies and in the interview he provides some good insights. Ant societies are well and truly socialist -- why so and why not human societies? The answer might lie in the differences in reproductive abilities. Long excerpts below:

There are about 9.500 known species of ants, many of whom you studied, but there is only one species of Homo. Why?

I think I have the answer for that. That is because we are so big. We are giant animals. The bigger the animal, the larger the territory and home range that the animal needs. Ant-species, consisting of very tiny organisms, can divide the environment up very finely. You can have one species that lives only in hollow twigs at the tops of trees, another species that lives under the bark, and yet another species that lives on the ground. Human beings, being giant animals and particularly being partly carnivorous, cannot divide the environment up finely among different Homo-species. There have been episodes in which there were multiple hominid-species, probably two or three species of Australopithecus, co-existing perhaps with the earliest Homo. But it is evidently the tendency of hominid species and particularly of Homo to eradicate any rivals. It is a widespread idea among anthropologists that when Homo sapiens came out of Africa into southern Europe about a hundred-thousand years ago, it proceeded to eliminate Homo neandertalensis, which was a native European species that had survived very well along the fringe of the advancing glacier.

You write that ants often share food among themselves. Why, and how did you find out?

Back in the fifties Tom Eisner, a colleague of mine, and I did I believe the first experiments tracing radio-active label led sugar-water through colonies of ants. We were able to estimate the rate at which the food was exchanged, and the volume that was exchanged. Not only do many colonies exchange food with fanatic dedication, but in the colonies of many ant species the workers regurgitate food back and forth at an extraordinarily high rate. Now we understand that the result of this is that at any given time, all the workers have roughly the same food-content in their stomach. It is sort of a social stomach. So that an ant is informed of the status of a colony by the content of its own stomach. It therefore knows what it should be doing for the colony. If you only had a small number of extremely well-fed ants and the rest were hungry, the workers would go out hunting for more food, whereas in fact it might be a bad time to hunt for food.

Why doesn't this sort of communism exist among humans?

What I like to say is that Karl Marx was right, socialism works, it is just that he had the wrong species. Why doesn't it work in humans? Because we have reproductive independence, and we get maximum Darwinian fitness by looking after our own survival and having our own offspring. The great success of the social insects is that the success of the individual genes are invested in the success of the colony as a whole, and especially in the reproduction of the queen, and thus through her the reproduction of new colonies.

This was I think one of the main contributions of the idea of kin-selection. We now understand quite well why most species of social insects have sterile workers, and therefore can have communist-like systems. In which the colony is all, the individual is only a part of the colony, and the success of the whole community is what counts far above the success of the individual. The behavior of the individual social insect evolved with reference to what it contributes to the community, whereas the genetic fitness of a human being depends on how well it can individually use the society. We have become insect-like only by extreme contractual arrangements.

You write that a major difference between humans and ants is that we send our young men to war, while they send their old females. Why is that?

Well first of all, all the worker-ants are female. In the bee, ant and wasp-societies sisters are extremely closely related to one another, and therefore it pays to be altruistic toward sisters, whereas brothers do not benefit by giving anything to sisters. So the females are the ones who are fanatically devoted to one another.

Why are they old? Once again it comes down to this matter of what is best for the colony. As the workers grow older, they put more and more of their time outside, and as they become quite old or injured or sick, they spend their time either outside of the colony or right at the edge. The advantage of this is that the individuals that are going to die soon anyway, having already performed a lot of services, are the individuals that sacrifice themselves. It is the cheapest for the colony.

Whereas in humans, not only are the young males the strongest, but by being mammals in a competitive society young males tend to be greater risk-takers, braver and more adventurous. They are moving up in the ladder of status, rank, recognition, and power. And to be a member of the warrior-class when it is needed, has always been a rapid way of moving up. So that appears to be the main reason why we send young men out, and they are willing to go.