Big bones

If the animal standing behind this man were alive, he probably wouldn't be smiling.

The skeleton he is standing in front of comes from an animal called the American mastadon. Although once there were many of them in North America, they have all been dead for over 10,000 years.

That might seem like a long time ago, but compared with when the first mastadon lived -- ?at least 40 million years ago -- ?it's not very long at all.

When they were living, mastadons were important to humans because humans used them for food. They probably weren't easy to kill though. Most humans probably did not want to get too close to those tusks!