When a dog hears its owner yawn, it's compelled to do the same, according to a new study.
Researchers recorded the sound of 25 dog owners yawning. They then played these to the pets, along with the sound of one stranger yawn.
They found the dogs were five times more likely to yawn when they heard their owner.
Lead researcher Karine Silva of the University of Porto, Portugal, said this indicated dogs had the capacity to empathise with humans.
A previous study by researchers from University of London's Birkbeck College found dogs can mimic yawning when they see a human doing it. But the latest research showed the bond goes even deeper as dogs responded in similar numbers to an audio recording of a yawn.
But Ádám Miklósi, an animal behaviour expert at the Eötvös Loránd University, in Budapest, raised a note of scepticism.