Ring-tailed lemurs are a chatty lot. They vocalize to exchange information. And they also communicate via a veritable smorgasbord of stinky secretions they use to mark their territory and advertise their romantic availability. But male lemurs, which have more scent glands than do females, are really masters of musk—because they sometimes mix their smelly secretions to produce a veritable bouquet of stank. And now researchers have a better idea why.

Male lemurs sometimes use the scent glands on their wrists to mark tree branches and saplings. Other times, they double down, rubbing their wrists against glands on their chests to create a foul and funky fusion. This special blend can then be smeared over objects or wiped onto their tails, which the males wave at their rivals in a display that scientists refer to as a “stink fight.”

But why create such a custom combination? Perhaps adding the oily exudate from the chest alters the information conveyed by the wrist. Or maybe it acts as a kind of preservative that makes the wrist signal longer lasting.

To find out, researchers gathered secretions from a dozen ring-tailed lemurs at the Duke Lemur Center in North Carolina. They then presented male lemurs with wooden dowels that were doused with either the wrist fragrance, the chest scent, or a mixture of the two. And they found that males spent more time sniffing the stick with the mixture, which suggests that the fragrant combination does contain more interesting information than the solo scents alone.

But the lemurs were even more interested in the odiferous amalgamation when it was left out to evaporate for 12 hours, licking the sticks to better access the dried volatile compounds. That observation supports the theory that mixing secretions actually boosts their staying power. The results are in the journal Royal Society Open Science. [Lydia K. Greene et al, Mix it and fix it: functions of composite olfactory signals in ring-tailed lemurs]

So while a rose is a rose is a rose, the perfume of the ring-tailed lemur is a complex concoction, the subtle meaning of which lies in the nose of the beholder.

—Karen Hopkin

[The above text is a transcript of this podcast.]