Brush, floss, and forget: Chances are, you only think about your teeth when they cause you trouble. But teeth have tales to tell, such as how old we are, how fast we grew, and how far we’ve traveled. Most intriguingly, teeth can tell us both what we evolved to eat and what we actually have been eating. Paleo-diet fans insist that our modern teeth troubles—all those pesky cavities—come from eating the wrong diet. If we only ate what our ancestors ate—meat, berries, and no grains—we’d be fine, they claim. But what do our teeth say? Tune in this episode to find out the toothy truth.
Our ancient ancestors had no teeth: They simply opened their mouths and filtered out food from the water. The evolutionary biologist Tanya Smith, the author of The Tales Teeth Tell, told us there are two main theories as to where teeth came from: They migrated to the jaws either from bumpy skin armor on the heads of ancient fish, or from little pegs found in the throats of weird, eel-like creatures known as conodonts. Either way, “once teeth took over, they really took over,” says Peter Ungar, a paleoanthropologist and the author of Evolution’s Bite. Tooth enamel is 95 percent mineral, and so, for the earliest toothed creatures, the acquisition of these peg-like accessories represented a Stone Age–style leap forward—they literally acquired a set of stone tools in their mouths.