According to research, it is likely that the culture of keeping pets began thousands of years ago, with our human ancestors capturing young wolves and domesticating them. The reason for adopting these furry predators was probably not for their cute faces, but because they were useful for hunting. Over time, these wolves evolved into a tamer species - dogs. According to a study published in May 2015, this evolution could have been as early as 27,000 years ago. So if we no longer hunt, why keep pets around now?  

Taking care of an animal can be extremely costly, as any pet owner might tell you. Due to cost, other theories suggest that owning a pet is a sign of a person's wealth. In order to properly care for an animal, one needs the resources to take care of themselves and the pet. "There's a lot of history and culture with how we chose to express this desire to look after animals, but basically it is a human instinct that used to be an honest signal of the ability to look after animals," veterinary scientist John Bradshaw told the BBC.

James Serpell, professor of Animal Ethics & Welfare at the University of Pennsylvania, believes that there are evolutionary benefits today to keeping pets. "Because we are such a social species," he says, "we are constantly seeking relationship with others – including with our pets. Humans which lack social support are more vulnerable to disease and infection."

Some disagree with the evolutionary benefits of keeping pets and believe that it is more of a fashion, a trend that is reinforced by its own popularity. Plus, we simply find different animals 'cute' at different periods of time.

Serpell disagrees though. He believes that pet-keeping occurred naturally in hunter-gather communities and so it must be inbuilt.

"The notion that pet-keeping could be sustained by fluctuations in fashion is incomprehensible because we know people are having these kinds of relationships with animals very early in their history."

Clearly, it's difficult to know exactly why humans keep pets. But keep them we do, and they enrich our lives in so many ways. That's reason enough for me!