Yawning

Yawning is a phenomenon. Like many phenomenon, there's more than one explanation for why and how it is triggered. With the exception of chimpanzees and dogs, animals lack a sense of empathy and are invulnerable to contagious yawning. Dogs have an admittedly strong connection with their owners, while chimpanzees display various character traits that indicate their sense of empathy. Both animals are prone to contagious yawning.

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