Although it's well known that yawning is contagious, even among mammals, not much has been discovered as to why - until now.
Researchers recently spent five months following two prides of lions living at the Makalali Game Reserve in South Africa and their findings give some idea as to why the weird phenomenon occurs.
One of the study's senior authors Elisabetta Palagi, an ethologist at the University of Pisa in Pisa, Italy, noticed that lions 'catch' each other's yawns.
Palagi said: "The data showed a clear picture: After yawning together, two lions would engage in highly synchronous behaviour."
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The study, which was published in the Animal Behaviour journal, found that the likelihood of a lion yawning was a massive 139 times higher if they had just seen another member of the pride yawning, as opposed to not seeing them.
After observing the big cats, the researchers found that spontaneous yawning mainly happened when lions were relaxed, or between waking and sleeping - this suggests that like humans, yawning can evolutionally be used to cool the brain and increase blood flow.
But, they also found that the lions would engage in the same behaviour after they caught another lion's yawn.
For example, if two lions were lying down and one yawned, the other would yawn. And then, if the first yawner stood up, so did the other lion.
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It seems to support the theory that contagious yawning evolved in order to boost the vigilance of a group of social animals, like wolves and chimps, according to Andrew Gallup, director of the Adaptive Behavior and Cognition Lab at SUNY Polytechnic Institute in Utica, New York.
Gallup added that it could mean that it has advantages for awareness and 'threat detection'.
Further research in humans has found that contagious yawning can be a way to empathise with others when they are experiencing a feeling or emotion. It can be stress, boredom or fatigue.
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And it's not just between members of the same species that contagious yawning can happen.
Researchers at journal Frontiers in Veterinary Science captured footage of elephants 'catching' yawns off their humans handlers, with the gentle giants yawning when their human handlers do.
Zoë Rossman from the University of New Mexico and her team spent two weeks observing the elephants at Knysna Elephant Park, a South African rescue facility for elephants.
Three elephants were spotted yawning in response to their human handlers, and nine instances of same-species (elephant to elephant) contagious yawning were observed.
Featured Image Credit: PA