Duke University researchers reports in the Febebruary 25th issue of the journal Biology Letters that lemur females carrying boys smell different from those carrying girls.
The results represent the first evidence in any animal species that a pregnant mother’s scent differs depending on the sex of her baby, said Christine Drea, a professor of evolutionary anthropology at Duke.
Drea and co-author Jeremy Chase Crawford of the University of California, Berkeley used cotton swabs to collect scent secretions from the genital regions of 12 female ringtailed lemurs at the Duke Lemur Center in Durham, North Carolina, before and during pregnancy.
Cat-sized primates with long black-and-white striped tails, ringtailed lemurs produce a musky odor that researchers jokingly refer to as “eau de lemur.”
The distinctive scent is a complex cocktail of pheromones and other chemicals that have been shown by previous studies to convey information about an animal’s sex, fertility, and other qualities.
In this latest study, chemical analysis using gas chromatography and mass spectrometry revealed that the hundreds of ingredients that make up each female’s scent change during pregnancy.
Expectant lemur moms give off simpler scents that contain fewer odor compounds compared with their pre-pregnancy bouquet—a change that is more pronounced when the moms are carrying boys, Drea said.
The patterns correlate with changes in blood hormone levels, the researchers found.