People have been using antibiotics for nearly 2,000 years, suggests a new study, which found large doses of tetracycline embedded in the bones of ancient African mummies.

What's more, they probably got it through beer, and just about everyone appears to have drank it consistently throughout their lifetimes, beginning early in childhood.

While the modern age of antibiotics began in 1928 with the discovery of penicillin, the new findings suggest that people knew how to fight infections much earlier than that -- even if they didn't actually know what bacteria were.