Why don ’t ants always fall for toxic bait? They may learn to avoid it

If you have an ant problem, toxic bait traps might seem like the perfect solution. There’s no spraying, no smooshing. After ants collect poison from the trap, they share it with the whole colony, wiping it out in one tidy, fell swoop. But toxic baits don’t always work as intended, and researchers have long puzzled over why. For Argentine ants, which are invasive in many parts of the world, the answer might be that they figure out how to avoid the toxic traps before they get wiped out, researchers report this month in Communications Biology . The finding raises new questions about how ants change their behavior in response to the toxins, says entomologist Michael Rust of the University of California, Riverside, who wasn’t involved in the new study. Still, he’s not quite convinced the authors have proved the ants are clever enough to detect the danger. It’s clear that “ants abandon baits,” he says. But, “The question is how that happens.” Colonies of Argentine ants ( Linepithema humile ) can contain more than 1 million individuals. The colony relies on specialized workers called foragers to find food. When a scouting forager finds a promising food source, she lays down a pheromone trail to lead other ants to it. This recruitment process allows thousands of ants to rapidly descend on tasty morsels, but it also makes them susceptible to toxic baits. These traps contain a delayed-action poison that kicks in after the ants...
Source: ScienceNOW - Category: Science Source Type: news