Learn how our bone density has changed over human history as our lifestyles have become less physically demanding.
1/18/17 | 4:15
11/9/16 | 5:08
4/12/17 | 5:51
5/9/17 | 3:53
2/15/17 | 4:05
12/21/16 | 5:10
7/26/17 | 3:39
