Is there anything more inviting than the drifting aroma of croissants as you stroll past a patisserie on a cold winter’s morning? We don’t think so. A new study published in the American Journal of Physical Anthropology has now for the first time established that humans aren’t the only primates who fall for fragrances that promise delicious rewards.
The lemurs enrolled in the research come from the Lemur Conservation Foundation in Florida. Here, they were challenged to locate containers hidden in the underbrush of their enclosure some of which contained real melon (cantaloupe, to be specific) and fake melon. The lures were spaced out between 4 and 18 meters (13 and 56 feet) from the melon-loving lemurs, but all were obscured from view to prevent any other senses from helping them in the task.
As the lemurs started tracking down the precious melon, it became evident that they were able to use their sense of smell as a means of sniffing out the goods. By following “odor plumes,” they were able to navigate the strength of the smell and after finding a box would start sniffing the air again to find the location of the next snack.
Interestingly, the lemurs could only find the cantaloupe when the wind was on their side, that is, blowing in a direction that carried the scent towards the lemurs’ noses. They also appeared to be able to remember where they had previously eaten, as when they approached areas where they’d already monched on cantaloupe they’d get on searching for the next stash.
A group of ring-tailed lemurs detect the smell of cantaloupe and track the aroma to the container of hidden melon. Two lemurs initially turn to the right, where fruit was previously hidden, while the others turn left, pausing to sniff along the way, and successfully find the hidden cantaloupe using their sense of smell.
Containers that were farthest away took the longest to find, and the top distance in a successful melon hunt was found to be 18 meters (56 feet) away from the path. They were also unable to find the fake cantaloupe containers, demonstrating that the presence of what looked like something delicious wasn’t enough to turn their heads.
"This is the first time research has demonstrated that primates can track a distant smell carried by the wind," said anthropologist and lead author Elena Cunningham, clinical associate professor of molecular pathobiology at NYU College of Dentistry in a statement.
"The lemurs were able to detect the smell of the cantaloupe among the complex smells of the forest and successfully navigate the odor plume to the fruit. The results indicate that olfaction may be used to respond to cues from distant sources. The ability to sniff out distant foods may be a critical foraging skill for lemurs and other primates."