Science & Tech

Taking a look at how ant (and human) societies might grow

2 min read

Social genes are key to colony growth

Edward O. Wilson has learned a great deal about life by studying ant societies. In this knowledge, he finds parallels between the social interactions of insects and those of birds, lions, monkeys, apes, and even humans. The last parallel got him into trouble in the late 1970s, but he now enjoys credit for establishing a new field of science – sociobiology, the influence of biology on human behavior.
Now Pellegrino University Professor Emeritus at Harvard, Wilson remains fascinated with the highly organized societies of ants, bees, wasps, termites, and humans. He and Bert Holldobler, with whom he shared a Pulitzer Prize for their book “The Ants,” have published a paper about how such societies originate, which appears in the September 20 issue of Proceedings of the National Academy of Sciences. The original colonies of humans, like those of ants and termites, they propose, could have arisen in much the same way.

Both ants and humans have achieved “spectacular ecological success,” they write. For humans, this includes winning out over competing forms of humanlike creatures who evolved from apelike ancestors. Ant-type societies may be a common reason for such success.

The standard theory of the rise of eusocieties, as these evolutionarily advanced colonies are known, credits altruism, behavior that benefits others at the cost of the individual. For an ant, that would mean giving up the privilege of reproduction to become a sterile worker or soldier in the colony. For a human, it might mean fighting a war in a foreign land.

In this model, kinship is key. An individual insect gives up its fitness to foster that of the kin group. The colony is built on close genetic relationships with a push from an environment in which food, water, and shelter are plentiful.

Wilson says that he “once promoted this theory, although evidence for it is sparse. In the last two decades, however, much new and more solid evidence has turned everything upside down.” He and Holldobler now believe eusocial colonies can grow and prosper without such kinships. In fact, biological nepotism could be disruptive, they say.