Durham, NC The social lives of ants, wasps and bees have long been a puzzle to scientists. How did complex insect societies colonies ruled by a queen and many workers come to be? A new model adds to discontent with old ideas.
Social insect society is divided into specialized castes that take on different roles within the nest. Most of the members of a colony the workers forego their own chance for reproduction and instead spend their lives raising offspring that aren't their own. Generations of scientists have tried to understand why. In other words, "what's in it for the workers?" said author James Hunt, who developed his model while at the National Evolutionary Synthesis Center in Durham, NC.
The question continues to spark debate. For the past 40 years, the dominant answer was based on the idea that having kids of your own isn't the only way to pass on your genes. According to a theory called Hamilton's rule, proposed in 1964 by British biologist William Hamilton, sometimes helping a relative can spread more of your genes to the next generation than having kids of your own. When the benefits to a queen outweigh the costs to her workers, the theory goes, altruism can evolve.
But there's one thing Hamilton's rule fails to consider. "Direct benefit to the worker is not part of the equation," Hunt said. According to Hunt, the evolutionary beginnings of worker behavior may be more selfish than they seem.
He bases his ideas on more than three decades of research on a family of wasps called the Vespidae, which is made up of nearly 5000 species. The majority of those species live alone, but some such as hornets, yellowjackets, and paper wasps live in complex societies with specialized castes that take on different tasks within the nest.
In paper wasps, for example, workers help build and defend the nest where they were born and feed and care for the larvae. By helping out around the nest, worker paper wasps a
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National Evolutionary Synthesis Center (NESCent)