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Why Do We Have 10 Fingers And 10 Toes?

Why not 5 or 15? Why is 10 the magic number when it comes to fingers and toes?

You may be wondering why we evolved to have ten fingers and ten toes. Why not eight, or only four?

The truth is that we don’t really know why ten became the magic number for fingers and toes.

Several Variations

We do know that fingers and toes, or claws come in several variations. Some mammals have five digits on each hand and foot. Others have fewer.

For example, horses have only one hoof per foot. And pigs and camels are cloven hoofed, meaning that they have two toes per foot. Squirrels have four toes on each front foot, and five each on the back feet.

More Fingers And Toes

Scientists also know that many animals used to have more fingers and toes. Back in the day, about 400 million years ago, the first vertebrates that crawled out of the ocean commonly had seven or eight digits per hand and foot. But then, for reasons that remain a mystery, a few digits faded away and ten or fewer became the norm.

Adapting For Change

This isn’t to say that all mammalian hands and feet are the same. Some animals have digits specifically adapted for climbing. Others sport ferocious claws. And, of course, we humans boast a handy opposable thumb.

But when it comes right down to it, we still share many traits with our fellow mammals. And having ten fingers and ten toes is one we share with many of them.

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