What’s the point of growing an extra set of molars if they don’t even fit in our mouths? We used to think it was all about genes leftover from prehistoric days, but more recently, the leading theory is that it’s actually about the foods we eat compared to what our ancient ancestors ate. Bone can atrophy or grow depending on what we put it through (kind of like muscle), and we simply aren’t giving our jawbones the same resistance our hunter-gatherer ancestors did.
Prehistoric people’s jaws got an intense workout from grinding up the fibrous plants and raw meat in their diet, which stimulated enough bone growth to make room for the third molars. Today, we eat softer foods that are cooked and processed, so it’s less common for someone’s jaw to grow big enough to fit the wisdom teeth. (Here at DentalCareXtra, we don’t recommend attempting to test this theory, though.)