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 ...

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 ...

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 ...

Some hold with the theory that the development of an embryo shows the stages of evolution. In other words, what first develops is fishlike, and then like a small mammal, and then like a lemur or ape, ...

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 ...

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