The arrival of the internet revealed an indisputable fact about human beings and the things that pique their interests: When given instant access to the accumulated knowledge of the entire human race, people will use it mostly to look at kittens.

That's not exactly true, actually, but it's pretty close. The Purina company, which makes Friskies cat food, claimed in 2013 that 15% of all web traffic is cat-related--but it turns out that may be just another urban legend. Kittens and cats play a lead role in videos, vlogs, blogs, and marketing campaigns, and they're the subjects of an endless ocean of memes and gifs. Celebrity felines like the recently deceased Grumpy Cat rack up hundreds of millions of views and earn millions of dollars for their lucky owners.

That's because, in part, domestic cats are among the most familiar animals on Earth--the World Atlas estimates there are as many as 600 million of them pouncing and purring across the world. People keep them inside and outside, and a lot of times, entire neighborhoods "adopt" a stray that everyone feeds, but no one actually owns. They've been used for centuries as pest control--and for good reason. Most people who have ever owned an outside cat are all too familiar with the gory trophies they're known to leave on front porches and stoops. Research published in the journal Nature Communications shows that cats kill as many as 3.7 billion birds every single year in the contiguous United States alone. But why do they do that?

Why do cats have whiskers? Why do they meow? Why do they nap so much? And answers to 47 other kitty questions:

Why do they meow? Why do they nap so much? Why do they have whiskers? Cats, and their undeniably adorable babies known as kittens, are mysterious creatures. Their larger relatives, after all, are some of the most mystical and lethal animals on the planet. Many questions related to domestic felines, however, have perfectly logical answers. Here’s a look at some of the most common questions related to kittens and cats, and the answers cat lovers are looking for.

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