Why we love kittens

It's not hard to see why cats hang out with humans - they get free food, warm houses and soft bedding. But why do humans let themselves get taken advantage of?

Although one can't generalise, most people find kittens beautiful and likeable, even people who have never owned a cat. Cat videos are among the most watched videos on Youtube and of course cats are the most common pets, (apparently only second to fish in numbers because you can’t keep over a dozen cats in a tank of water).

According to researcher Carlos Driscoll and his colleagues, most animals were domesticated via artificial selection - that is, some animals could be useful to humans and therefore humans adopted them. This is however not true with cats - and to a lesser extent with dogs - which mostly 'domesticated' themselves. (If we define 'domestication' for cats as 'made themselves at home in our houses').

In a PNAS article (Proceedings of the National Academy of Sciences of the United States of America, https://www.pnas.org/content/106/Supplement_1/9971) 'From wild animals to domestic pets, an evolutionary view of domestication' Driscoll explains that 'wild cats initial domestication and their evolution to companion animals was primarily a process of natural, rather than artificial, selection over time driven during their sympatry with forebear wildcats.' ('Sympatry' describes species that occur in the same place at the same time.)

This sympatric evolution probably first began in ancient Egypt but traces of cat bones have been found in human habitations long before - in fact some of the earliest date to about 7000 BC. However, it is uncertain whether the cats in these early cases were pets or dinner. (https://www.knowyourcat.info/lib/egypiancats.htm)

So why do we like cats so much? According to Shannon Odell, a PhD neuroscience candidate, it is all to do with how our brains are wired. In her lively video podcast entitled 'Neuroscience explains why you can't help but love kittens' (https://www.inverse.com/article/45559-neuroscience-brain-on-kittens-why-we-love-them ) she explains that our brain perceives kittens in a similar way that it perceives babies, and we are hardwired to love babies because humanity would quickly become extinct otherwise.

Consequently, whether we like it or not, the big eyes and round faces of kittens switch our brains to caregiving mode. Interaction with a kitten causes our brains to produce a neurotransmitter called Oxytocin. Oxytocin, which is produced in the hypothalamus and released in a small gland called pituitary gland, a pea-sized structure at the base of the brain, was first recognised for its role in the birth process, and also in nursing (according to Larry Young, a behavioral neuroscientist at Emory University in Atlanta, Georgia). Now we know that Oxytocin has a much wider and more complex function and is a crucial player in social bonding, trust and attachment.

When it comes to interaction with humans, besides big eyes and round faces, the only thing preventing kittens and adult cats from having more tricks up their sleeves is a lack of sleeves. They have tricks aplenty. A cat's purr, for example, is beneficial for kittens and humans. The purr gently vibrates the body at a frequency which seems to help with bone growth and muscle stimulation - very useful for a growing kitten, but also giving positive feedback to the human pleasing the cat. It's good for the human too, as humans who live with cats tend to have lower blood pressure and seem to suffer less from other heart conditions. Some doctors are convinced enough of these benefits to allow cats as therapy animals in their hospitals (https://www.knowyourcat.info/info/purr.htm).

But wait! Is that purr always the same? A very interesting study by researcher Karen McComb has shown that a hungry cat can alter her purr and mix in an additional 'cry-like' sound. The frequency of this sound is close to that of a crying baby, and though it is more subtle, our subconscious nevertheless detects the frequency and this spurs us to want to do something about it, such as open another can of cat food. (https://www.knowyourcat.info/info/solicitpurr.htm). Karen McComb, calls this purr/cry combination a 'solicitation purr'. She describes it in Current Biology (Volume 19, Issue 13, R507-R508, 14 July 2009, https://www.cell.com/current-biology/fulltext/S0960-9822(09)01168-3) under the title 'The cry embedded within the purr'.

So it seems that we can't help but love kittens and cats alike, but do cats reciprocate and actually care about their human companions, or are we just walking food dispensers? In one study which aimed to answer this question, cats were presented with 4 choices: toy, food, interesting smell or interaction with their human. In the end humans were the winners. So yes, while your individual mileage might vary, most cats do bond with their humans - they just don't want to be obvious about it. After all, they have their aloof mystique to maintain.