House cats are much noisier than feral cats, although they have fewer vocalizations than some other species. Why do house cats have so many vocalizations compared with wildcats? The exceptions are the big cats-lion, tiger, jaguar and leopard-whose voice boxes are modified so that they can roar. Most species of wildcats can purr, including the cheetah. That’s why cats can purr when they’re breathing in and breathing out. The purr is an unusual vocalization, made by rattling the vocal cords together rather than vibrating them by pushing air past them, which is how cats-and humans-generate all their other vocal sounds. So purring doesn’t always mean “I’m happy.” Some researchers have claimed that the vibrations from purring might help heal bone damage in an injured cat. Yet sick cats will also purr as a cry for help. The vibrations emanating from the purr certainly have a calming effect on people. This capacity has not emerged during the 10 million years of felid evolution, so it seems unlikely to arise spontaneously in our domestic cats.Ĭats purr because they have something to say, which roughly translated is “please keep still and pay attention to me.” Kittens purr to persuade their mothers to keep on nursing them, and pet cats purr when they want to be stroked. To expand their diet, cats would have to evolve physiological traits that allow them to synthesize these and other key nutrients from plant foods. Whereas dogs (and humans) can synthesize these substances from plant-based precursors, cats have to obtain them from meat. In contrast, the cat family, known as Felidae, lost the genes that encode several key enzymes-including those that manufacture vitamin A, prostaglandins and the amino acid taurine-early in its evolution. Having more copies of this gene has allowed dogs to eat a more omnivorous diet. Recent DNA analyses indicate that over the course of their evolution, dogs have acquired more copies of the so-called amylase gene, which makes an enzyme that helps to break down starch. Will cats, which require meat, eventually evolve to eat a broader array of foods as dogs do?Ĭats and dogs belong to a group of mammals known as Carnivora, and the wild ancestors of both species dined primarily on meat. As they adapted to living alongside humans, cats became more sociable with one another and much more accepting of people, but there is no evidence that they have changed much more than that over the past few thousand years. Bradshaw is a visiting fellow at the University of Bristol School of Veterinary Sciences in England, where he studies the behavior and welfare of cats and dogs, as well as their interactions with people.Īre cats less domesticated than dogs? Are they becoming more domesticated over time?Ĭats are far more similar to their wild ancestors than dogs are to wolves, so dogs are in that sense the more domesticated of the two species. Here John Bradshaw, author of Cat Sense (Basic Books, 2013), fields a selection of questions submitted by Scientific American editors and Twitter followers about the cat’s many quirks. As anyone who has spent time with cats knows, our feline companions are mysterious-much more so than those other furry family members.
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