Hadza

In the past century, many Americans have lost the ability to sit in a way that doesn't strain their backs. Specialists say we could take a lesson from excellent sitters from other cultures.

What made us human might have had less to do with men out hunting, and a lot more to do with what was going on at home — with grandmas and babies.

Some species of bacteria in our intestines are disappearing. Can we reverse the microbial die-off? The food eaten by Tanzania's Hadza tribe could hold the answer.