When your cat refuses to eat the food you lovingly laid out for her, you probably assume she's just doing it to secretly delight in the frustration on your face. You give in to her devices and try to fancify the feast, adding some freshly caught fish, but she just sniffs it and slinks away.
"Okay," you say. "Why don't you just go get a job and buy your own food, then?"
But even though cats do tend to scheme, this time, there's actually good reason for it. In a study published online last week in the journal Royal Society Open Science, researchers found that cats' pickiness is not based on smell, taste, or texture. What matters most, apparently, is nutrition.
As it turns out, cats are driven to eat foods with a preferred ratio of protein to fat: 1 to .4.—which translates to about 50:50 in terms of percentage of energy from protein and fat. Yes, seriously.
Compared to its archnemesis the dog, who will scarf down just about anything—including socks—the cat, unsurprisingly, has a much more sophisticated palate.
The researchers gave cats different flavors of foods over the course of several weeks, some of which seemed very cat-friendly (rabbit, fish) and one of which did not (orange). At first, the animals went for the rabbit- and fish-flavored foods, but over time, that changed.
“Cats initially selected food based on flavor preferences, but after ‘learning’ (due to prior exposure) about the nutritional composition of the foods, cats selected foods to reach a particular target balance of protein and fat regardless of added flavors,” study-leader Adrian Hewson-Hughes told the Discovery News site Seeker.
As the study wore on, the cats gravitated to the orange-flavored foods which had a very particular protein-to-fat ratio, even though it wasn't as pleasing to their feline taste buds.
Which is all to say that cats are a lot more human-like than we ever imagined. The burger might tempt us with its taste, but we know we should probably turn to the salad instead. But cats seem to possess even more self-control than we do.
So, if cats are this in touch with their nutritional needs, it's probably safe to assume they are quietly judging us from the corner when we don't give ours the attention it deserves.