The sled dogs that compete in Alaska’s annual Iditarod run about 1,100 miles in less than two weeks, often in temperatures as low as -40 degrees F. “They use fat as their primary energy source—far better than any other athletic species that’s been studied,” says exercise physiologist Michael Davis, who notes that a 55-pound husky can burn as many as 12,000 calories a day. Davis’s research has also shown that sled dogs have an enormous capacity to process oxygen. Cats are more like sprinters: They’re capable of short bursts of energy but lack the aerobic endurance of ultra-runners like huskies.
Which Are More Agile?
“Cats are very nimble, with great balance,” says New York City veterinarian Michael Garvey. “When a cat falls off a bookshelf, it usually lands on its feet.” And when cats take a longer plunge, their body control is even more on display. “Cats that fall large distances typically don’t land on their feet, but given enough time, they are able to right themselves. They contort their bodies so they are falling flat, which allows them to land on their chest and belly, reducing their injuries,” says Garvey. He should know: He’s the former director of an animal hospital in Manhattan that treated up to 250 falling felines each summer. He and his colleagues cataloged the injuries and discovered a surprising trend: Cats that fell from higher than 10 stories up actually fared better than those that fell from between five and nine stories. Garvey believes the added height gives cats the time to position themselves for a perfectly splayed-out landing. “I’ve seen cats that have fallen more than 32 stories and didn’t have serious fractures,” says Garvey, who conducted a follow-up study on dogs. “Sadly, most dogs that fall even four stories don’t survive, because they lack the ability to compose their bodies midair.”
Which Are Better Hunters?
Many kinds of dogs have been meticulously bred to assist humans in hunting, but cats are arguably more effective as independent assassins. “Some dogs will chase squirrels all day long, but if they do get one cornered, they often won’t know what to do with it,” says animal behaviorist Monique Udell, who has worked with both cats and dogs. “Cats will almost always go in for the kill.” Cats’ superior close-range and nighttime vision contributes to their hunting prowess, as does their ability to focus intensely on the task at hand. In fact, their skill as hunters has been documented: A 2010 University of Nebraska report found that feral and stray cats kill as many as 480 million birds in the U.S. each year—that’s approximately eight Tweeties for each Sylvester.
Which Are Hardest Working?
Both cats and dogs were originally brought into the human fold for practical reasons (cats to kill vermin, dogs to hunt and to herd). But these days, dogs have by far the more diverse résumé. Their job skills are almost as wide-ranging as humans’: Dogs guide the blind, chase down criminals, and sniff out illegal drugs. They’re called in to detect termites, to identify gas leaks, and even to help schoolchildren with ADHD concentrate. (They’re still pretty good at herding cows and sheep, too!) Meanwhile, though cats are sometimes recruited to control rodents, in general they lack dogs’ versatility—and drive. According to a recent study, the average house cat spends 80 percent of the day in repose.
Which Live the Longest?
Cats have an average life span of 13 or 14 years, as opposed to just shy of 11 years for their canine rivals. “For dogs, there’s a huge difference depending on the size of the animal—the really large dogs tend to have considerably shorter lives,” explains Stanley Coren, an animal behaviorist. “A Newfoundland is quite old by the time he’s 8 or 9. A miniature poodle might live for 14 or 15 years.” For cats, the main age variable is environment—outdoor cats don’t live nearly as long...