Cats can identify owners from strangers by scent:
The study by Tokyo University of Agriculture found cats spent significantly longer sniffing tubes containing the odours of unknown people compared to tubes containing their owner’s smell.
This suggests cats can discriminate between familiar and unfamiliar humans based on their odour, the researchers say, but that it is unclear whether they can identify specific people.
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In the study published on Wednesday, researchers presented 30 cats with plastic tubes containing either a swab containing the odour of their owner, a swab containing the odour of a person of the same sex as their owner who they had never met, or a clean swab.
The swabs containing odours had been rubbed under the armpit, behind the ear, and between the toes of the owner or stranger.
Cats spent significantly more time sniffing the odours of unknown people compared to those of their owner or the empty tube, suggesting they can discriminate between the smells of familiar and unfamiliar people, the researchers said.
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“The odour stimuli used in this study were only those of known and unknown persons,” said one of the study’s authors, Hidehiko Uchiyama.
“Behavioural experiments in which cats are presented with multiple known-person odour stimuli would be needed, and we would need to find specific behavioural patterns in cats that appear only in response to the owner’s odour.”
See Tim Dodd, Cats distinguish owner’s smell from stranger’s, study finds, BBC, May 28, 2025.