"It's like singing a duet, but with smells instead of sounds," said Christine Drea, a Duke University professor who supervised the study at the Duke Lemur Center in Durham, N.C.
Duke researchers analyzing scent secretions of lemurs at the center and monitoring their scent-marking behavior across the breeding season said they found mated lemurs mirror each other's scent-marking behavior, and that lemur couples with offspring give off similar scents -- possibly as a way to combine territory defenses or to advertise their relationship status to the rest of their group.
After they reproduce, they smell more like each other, the researchers said.
Lemur couples without offspring that spend more time on scent-marking and investigating each other's odors may be in a "getting-to-know-you" period, they said.
"If two animals have never reproduced, the male doesn't necessarily know what the female smells like when she's in heat, because they've never gone through this before," researcher Lydia Greene said. "They might need to scent mark a lot more to figure out when it's time to mate."
Once mated, though, they begin sharing similar scent signals, she said, possibly jointly defending their territories or advertising their bond to other lemurs in the group.
"[They could be saying] we're a thing. We've bonded. Don't mess with us," Greene said.