Cat are known as finicky eaters, and my current fur babies are no exception. Iggy and Spud have turned their noses up at a variety of flavors in their two short years with us, but things finally clicked when we introduced them to premium tuna cat food. Suddenly it was all they wanted–and nothing else.
Iggy and Spud aren’t alone in their love of tuna. The dish is a staple of everything from New Yorker cartoons to Meow Mix jingles. And fish in general is such a hit with felines that an estimated 6% of all wild fish caught gets turned into moist cat food alone. That’s an odd diet for an animal that evolved in the desert.
Now researchers think they know why our feline friends have this curious craving. As I write in Science, researchers have discovered that cat taste buds contain the molecular machinery needed to detect umami. That’s the savory flavor of various meats, and one of the five basic tastes in addition to sweet, sour, salty, and bitter. But the feline palate isn’t just find tuned to meat–as one might expect for an obligate carnivore. The team of scientists also discovered that the cat’s umami receptor responds especially vigorously to molecules found in tuna. In taste tests, cats in the study preferred water flavored with these compounds over all other dishes. Tuna appears to hit the “umami sweet spot” in cats, as one of the researchers told me.
Still, it’s unclear why cats would have evolved a taste for tuna. It may have become a useful adaptation to living with humans. As far back as 1500 B.C.E., cats are depicted eating fish in the art of Ancient Egypt. And by the Middle Ages, felines in some Middle Eastern ports were consuming large quantities of fish—including tuna—likely because they were feasting on the scraps left by fishers. Cats that had a hankering for tuna likely had a leg up on their fish-averse comrades.
If your own cat doesn’t like tuna, don’t sweat it. Researchers have shown that cats aren’t able to tase sugar, but my cat Jasper used to love marshmallows, which are basically just sugar and more sugar. Some feline mysteries, it seems, can’t fully be explained by science.