The Ash Twins Blog

Another great NYTimes book review, this time by Steve Jones on The Superorganism, a new tome on the social insects: wasps, bees, ants, and termites.

Hölldobler and Wilson’s central conceit is that a colony is a single animal raised to a higher level. Each insect is a cell, its castes are organs, its queens are its genitals, the wasps that stung me are an equivalent of an immune system. In the same way, the foragers are eyes and ears, and the colony’s rules of development determine its shape and size. The hive has no brain, but the iron laws of cooperation give the impression of planning. Teamwork pays; in a survey of one piece of Amazonian rain forest, social insects accounted for 80 percent of the total biomass, with ants alone weighing four times as much as all its mammals, birds, lizards, snakes and frogs put together. The world holds as much ant flesh as it does that of humans…

A few simple rules produce what appears to be intelligence, but is in fact entirely mindless. Individuals are automatons. An ant stumbles on a tasty item and brings a piece back to the nest, wandering as it does and leaving a trail of scent. A second ant tracks that pathway back to the source, making random swerves of its own. A third, a fourth, and so on do the same, until soon the busy creatures converge on the shortest possible route, marked by a highway of pheromones. This phenomenon has some useful applications for the social animals who study it. Computer scientists fill their machines with virtual ants and task them with finding their way through a maze, leaving a coded signal as they pass until the fastest route emerges. That same logic helps plan efficient phone networks and the best use of the gates at J.F.K. In the phone system each message leaves a digital “pheromone” as it passes through a node, and the fastest track soon emerges. Swarm intelligence does wondrous things

Swarm sex is even more remarkable… the sting-less male’s only job is to inseminate females, who sting and sting again in defense of their nest. The queen herself packs a punch, although most of the time she is too busy to do much damage. Among the leaf-cutter ants, “Earth’s ultimate superorganisms,” with their uniquely intricate societies, a single queen may produce as many as 200 million female (and sterile) offspring in her lifespan of 10 to 15 years, together with a few males, whose only job is to replenish the sperm supply…

The world of superorganisms varies from that of the relatively primitive “dawn ants” of Australia, which live in groups of a hundred or so separated only into sexual and asexual kinds, to the leaf-cutters, found only in the New World, who cultivate fungal gardens and have millions of workers, divided into a diversity of castes, in a single colony. The whole place buzzes with information, passed on with chemical cues, taps and strokes, dances and displays…

[A]nyone interested in what real biology — the study of life, rather than of chemistry — is up to nowadays could do no better than read this volume.