Sense of smell part of 'remarkable social cognitive abilities’

Pet cats can tell their owner’s smell apart from those of other people, new research suggests.

Scientists at Tokyo University of Agriculture formed their conclusion after completing an experiment in which cats sniffed three test tubes containing cotton swabs - one swabbed from their owner, another from a stranger and a third blank tube.

Swabs were taken from behind the ear, the armpit and between the toes.

Researchers found that moggies tended to sniff the unknown scent much longer than their owner’s swabs, with them showing the least interest in the blank control.

Cats sniffed at the unknown odour tube for about 2.4 seconds, the known odour for about 4.8 seconds, and the blank tube for just 1.93 seconds.

“Cats spent a substantially longer time sniffing the odor of an unknown person than that of their owners,” the study said.

The research team further found that cats who sniffed the blank tube first tended to have more neurotic personalities, while those that smelled the known odour first were more outgoing.

Another finding was that our feline friends tended to use their left nostril to sniff a tube to their right and their right nostril to sniff a tube on their left, with no obvious nostril preferred for a tube in the middle.

Authors remarked that cats, with study authors described as ‘popular companion animals’, have ‘remarkable social cognitive abilities’, though research among them is less advanced than among dogs.

They said previous studies suggest that cats can sniff out the health and sexual status of other cats and exchange smells through rubbing against each other, with nests marked by mother cats having a calming effect on her kittens.

Cats can also tell humans apart by their voices and follow a human’s gaze to find hidden food.

In their published research article, entitled Behavioral responses of domestic cats to human odor, the study authors, comprising Yutaro Miyairi, Yuichi Kimura, Koji Masuda and Hidehiko Uchiyama, said: “Cats are known to respond differently to familiar and unfamiliar people.

“Weaned kittens sniff unknown female cats longer than they sniff their mothers.

“During habituation and de-habituation trials, cats alter their responses to known and unknown stimuli.

“Our results suggest that they may be able to discriminate between known and unknown humans based on their odor.”

In their conclusion, they added: “In this study, we described the behavioral responses of Felis catus to human olfactory stimuli.

“We suggest that cats use their olfaction for the recognition of humans.

“In addition, we suggest that olfactory exploratory behavior in cats is related to personality features and that there is lateralization of the left and right nostrils in the detection of odors.
 “This lateralization may have been influenced by the differences in brain hemisphere function.

“Lastly, we record characteristic rubbing (marking) behavior occurring after sniffing, indicating that sniffing may be an exploratory behavior preceding the rubbing of odor (marking) in cats.”

The full research article was published by the California-based Public Library of Science, so please note the US spelling of words such as 'behavior' and 'odor', and can be viewed at journals.plos.org