Humans have many wonderful qualities, but we lack something that’s a common feature among most animals with backbones: a tail. Exactly why that is has been something of a mystery. Tails are useful for ...

Like spider monkeys, our ancestors’ tails helped them stay balanced in trees (Getty Images/iStockphoto) For half a billion years or so, our ancestors sprouted tails. Like fish, they used their tails ...

For half a billion years or so, our ancestors sprouted tails. As fish, they used their tails to swim through the Cambrian seas. Much later, when they evolved into primates, their tails helped them ...

A highly effective tail is needed in order for a sperm to be able to swim, and for a baby to be conceived. By using cryo-electron tomography, researchers have identified a completely new nanostructure ...

If you've ever wondered why seeing a dog wagging its tail makes you so happy, science might have an answer. Humans' relationship with pooches stretches back to the dawn of civilization, but it has ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. Humans have many ...

Tails are a common feature across the animal kingdom. Nearly every class of vertebrate has them. Reptiles use them for self-defense and attacking prey. Tails help with balance and communication in ...