Oh, hai! I’ll admit it upfront: I’m a sucker for cat pictures and videos. When the latest kitteh goes viral, you can bet it will turn up on my screen. But I’m hardly alone. These silly videos of cats, kittens and other things that make us go “Awwwwwwww” are overwhelmingly popular. Why is it that we can never get enough? (Warning: intense cuteness follows!)
This latest video of a mama cat and her oh-so-adorable-kitten illustrates all of the key elements of cuteness. The kitten is clumsy. It’s vulnerable and has big, wary eyes. It emits piteous high-pitched mews. And then mommy rushes in to defend her baby. (More on Time.com: Were You Born This (Un)Happy, or Did You Marry Into It?)
Like this kitten, virtually all cute things are small — or, at least, small in comparison to other similar items or animals. If they have eyes, they are disproportionately large. If they make sounds, they tend to be high pitched. And they are usually comically inept in a way that makes them seem in need of protection.
What do big eyes, small bodies, vulnerability and high-pitched sounds have in common? Collectively, they are the characteristic features of babies — human and other. In mammals like us, these essential qualities of “cute” typically trigger an almost automatic nurturing response.
Although adults tend to trivialize cuteness as silly and trite, the ability to appreciate it is actually a critical adaptation, honed over the eons to ensure that we take care of our young. Cuteness lifts our mood and is inherently pleasurable, which tends to mitigate the many, many aspects of parenting that are not fun at all. (More on Time.com: How Much Happiness Can Money Buy? About $75,000 Worth)
If babies weren’t cute, we might be more likely to kill the noisy, demanding, frequently smelly creatures than to care for them. So, they need something to trigger a caring response. What better way to keep us hooked than to make us happy?
Witnessing cuteness is basically instant Prozac. In fact, when the same pleasure systems in the brain are misdirected into compulsive behavior, it’s usually called addiction.
Unsurprisingly, the response to cuteness is associated with female hormones. One study found, for example, that variations in hormones due to menopausal status or use of birth control pills affected the response to cuteness: premenopausal women and those on the Pill (which simulates pregnancy) were generally more attuned to it than older women and men.
Cats, dogs and other pets take advantage of this nurture instinct. And the Internet lets us take advantage of it too — by giving people the chance to send around a dose of cuteness to spread cheer. (Lolcats grammar continues to be defective, however, if in a pleasantly consistent way.)
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