Ants misbehaving Ants misbehaving (July 03, 2002)

They came by ship -- workers, soldiers, even queens -- and claimed California from the indigenous population. The invaders in question are Argentine ants, which first hitchhiked to the West Coast on merchant ships around 1900 and are wiping out native ants.

Nicole Heller, a biology graduate student at Stanford, wants to know why.

At two local sites -- Jasper Ridge Biological Preserve and a field at Peter Coutts Road and Stanford Avenue -- she is studying how Argentine ants communicate and organize themselves.

Biologists think Argentine ants owe their success in part to cooperation, Heller said. Unlike other species, which succumb to infighting with neighboring colonies, Argentine ants work together -- even if introduced to colonies thousands of miles away. That behavior may help them compete better for food, reproduce in larger numbers, and fight other species effectively.

In fielding questions from curious passersby, Heller has been intrigued to find that many local residents are conducting research of their own; some have spent hours recording Argentine ant trails through their homes.

"I think ants fascinate people because they're social," Heller said. "People think they're a little like us."