A Tiger On Your Lap?

Your cat stands on its back legs by the couch, reaching up, up, up before hooking its claws into the upholstery and giving a scratch or two. What's up with that? Is your cat just being naughty? No, it's being a tiger.

Inside every Beauregard, Sneezers, Ollie and Bongo lurks a tiger, lion, jaguar or lynx. It's been a mere 4,500 years since the first cats were lured out of the deserts and forests and into the circle of human companionship. Respectively, forty thousand years earlier, dogs began doing our bidding - and liking it.

All felines, whether they tip the scales at 14 or 400 pounds, are akin at the cellular level, with 38 chromosomes per cell. But their similarity goes beyond biology, as any cat observer knows.

Tammy Quist, director of Wildcat Sanctuary, Inc., in Sandstone, Minn., has ample opportunity to observe and compare the big cats, the small wild cats and her own trio of housecats.

Marking what's theirs

When the big cats rear up on their hind legs against a tree, they're marking their territory. And so is your housecat - but it also may be stretching to realign its vertebrae.

Cats, regardless of size, are fiercely territorial. Has your cat ever come up and rubbed its face against yours? You've just been marked with the scent glands in its cheeks. The big cats do that, too, except to trees, rocks, etc. All cats have another delightful way of marking boundaries - spraying urine. If you think your Mittens is bad, imagine a tiger who can spray a stream up to 12 feet.

Play or hunting practice?

Right up there with marking is hunting. When your Hugo leaps for a twist of paper on the end of a string, that's not just play, it's hunting practice. The technique is the same, whether a cat is big or small: a crouched, virtually silent approach (thanks to putting the back foot where the front foot has just been), a pause, a powerful spring and a swift killing clamp of jaws.

"The result is often the same, too," says Quist. "If a cat's hungry, it will eat its prey. If not, it will torture it."

Part of what makes the powerful spring possible is a cat's tail. All cats that attack by pouncing have long, muscular tails that act as a counter balance when they leap. Wild cats like bobcats have very short tails because they ambush their prey; a long tail would rustle and get in the way.

18-hour catnaps

Speaking of nighttime, big cats and house cats both have formidable vision that's nearly six times as acute as ours. Quist says they don't see in full color, it's more of an infrared range to allow them to hunt at night. One difference: house cats have vertical pupils, while great cats' are round like ours.

Quist says cats share other similarities:

•Their teeth are the same, but great cats' are bigger.

•Give them an expensive toy, and they ignore it in favor of the homemade one.

•If you're allergic to a housecat, bring the Claritin if you're near a big cat.

•All cats but cheetahs can retract their claws.

•All cats, no matter the size, eat grass and throw up.

So the next time Butterscotch curls up on your lap, remember: the heart of a tiger beats beneath that well-groomed coat.