Ants have a remarkably sophisticated sense of smell, allowing them to pick up odors that dictate how they behave and how they interact with each other.

Each ant has a subtle, individual aroma, made from a blend of chemicals called pheromones stuck on the outside of its body. Minute differences in each ant’s body odor provide behavioral cues that allow the insects to maintain complex social colonies with different roles for queens, workers, nurses and soldiers. Using sensitive antennae, they can even sniff out an intruder from another colony, said a study in Cell Reports.

Anandasankar Ray, an entomologist at the University of California, Riverside, and his team began by putting Florida carpenter ants (Camponotus floridanus) on glass slides under a microscope and zooming in 1,000 times on their antennae, so they could see the hundreds of tiny sensory hairs that coat them. Next, they inserted a very thin glass electrode into a single sensory hair in order to record any biochemical activity on the insects’ antennae. In doing so, they were able to pinpoint the exact chemicals that ants could smell emitting from the queen, the workers and from ants from another colony.

“It was really surprising,” Ray said. “The ant was able to sense a very large number of [chemicals].” Ants’ ability to distinguish their colony-mates’ body odors is similar to a sommelier’s ability to sniff a glass of wine and tell the difference “between a chardonnay and a Pinot Noir,” Ray said.

Los Angeles Times