In tests with hidden speakers, cats showed signs of surprise when their owner's voice seemed to quickly "teleport” from one place in the room to another.
Previous studies of cats (Felis catus) have shown that they are able to track objects disappearing from view, demonstrating the level of so-called “object constancy” - the awareness that an object continues to exist, even if it is no longer visible. But few studies have tested how cats use other senses to track objects and people.
Sakho Takagi from Kyoto University in Japan and her colleagues tested the hearing of cats by studying how they react to the voice of the owner. To do this, they studied 50 domestic cats – 27 of them live in "cat cafes” where people can pay to watch and play with cats, and the remaining 23 were domesticated.
The team placed each cat alone in a room with two doors and a window. They placed a speaker outside the room near one door and a second speaker outside near the second door or window. These two speakers were at least 4 meters apart from each other. To watch the cats, the team installed five video cameras in the room.
During each test, the researchers used speakers to play a recording of the voice of the cat's owner – a cafe owner or family member-or a stranger calling the cat by name. The voice was played twice with an interval of 2.5 seconds and could sound either from the same speaker both times, or once from each speaker.
Then eight people evaluated the reaction of each cat, carefully analyzing the video. The results showed that the cats did not show much surprise – this was evidenced by moving their ears or changing the direction of their head - when their owner's voice sounded twice from the same speaker, or when a stranger's voice sounded either twice from the same speaker, or once from each speaker.
But when the familiar voice of the cat's owner sounded first from one speaker, and then from a second speaker located at a distance of 4 meters, after only a few seconds, the animals showed signs of surprise.
The authors suggest that they can mentally track the location of their host by his voice and therefore show surprise when their hosts suddenly “teleport” to a new place. The results obtained indicate a previously unknown socio-spatial awareness of cats.