Dog tail

For some creatures, tails have some pretty spectacular uses.

Geckos, for example, are capable of shedding their tails when they feel threatened. Believe it or not, the disconnected tail will continue to wiggle in order to distract predators while the gecko makes a quick getaway.

Opossums have prehensile tails, which they can wrap around branches to help them scale trees. And some birds, such as peacocks, use their tails to attract the boys.

Why Do Cats and Dogs Have Tails?

For the most part, canines and felines use their tails to communicate — from the wide, sweeping wag of a happy dog to the quick tail swish of an annoyed cat.

In canines, a tail may also serve as a type of rudder to help stabilize dogs in the water. In some cases, it can also entertain a bored dog who will chase it in relentless circles.

Although both dogs and cats have supracaudal glands on the surface of their tails, the reason for this is unknown. In dogs, the scent of these glands may help identify them to other canines. In cats, excretions from these glands may be used to mark territory.

Do Cats and Dogs Really Need Them?

Although the early Romans believed that docking a dog’s tail could help prevent rabies, we know that’s just not the case. But some canine breeds, such as working or hunting dogs, have had their tails cropped to make it easier to do their jobs; this remains a controversial practice because many veterinarians question the ethics and medical necessity of tail docking.

Since many pets are born with little to no tail, such as Manx cats, it’s pretty clear that a long tail isn’t necessary for a happy life.

Of course, there’s nothing quite like the sound of an energetic "welcome home!" tail thumping against the floor. So even if tails have no other use, this is enough in and of itself.

For answers to other curious questions about animals, check out our other "What's the Deal With . . ." stories.