Ant genome reveals secrets to success, clues to defeat
Anyone who has spent time around Berkeley has likely had to deal with legions of marching ants invading their kitchens.
Now a research team has unlocked the genetic code of the Argentine ant, providing clues as to why this species has been such a successful invader—and why they can often be found swarming minuscule or even invisible food sources.
Scientists have found that these South American pests have a huge number of sensory receptors for taste and smell. "They are covered with sensors," says Neil Tsutsui, an associate professor in the Department of Environmental Science, Policy, and Management, and lead author on the study, which was published in the Proceedings of the National Academy of Sciences in January 2011.
Argentine ants have 367 genes for sensory receptors for odor and 116 for taste, the study found. By comparison, the honeybee has 174 genes for odor"less than half as many as the ant"and 10 for taste. But this is about more than household pests. "The Argentine ant is a species of particular concern because of its enormous ecological impact,"? said Tsutsui. "When the Argentine ants invade, they devastate the native insect communities while promoting the population growth of agricultural pests."
The genome map will help researchers understand and manipulate genes to interfere with mating, break up the super-colony running the length of California, develop repellants, or simply attract ants to a trap.
How does understanding these sensory markers help? For example, Tsutsui said that identifying the biological chemicals that ants use to tell friend from foe might make it possible to spray a nest with naturally occurring chemicals that trick the ants into thinking that they've been invaded. "Triggering their aggressive behavior would let the ants kill each other off and thus eliminate the need for pesticides,” Tsutsui said.
The ground-dwelling species also appears to have the capacity to adapt to the variety of poisons they encounter in their foraging: they have a high number of genes that help detoxify harmful substances. Tsutsui says knowing where these genes are could help researchers learn whether the ants are developing a resistance to pesticides.
Researchers caution that there’s no quick fix. They say the next step on the path to real-world applications is to study these genes in the lab and the field to confirm the genomic findings.