"Why Early Humans Had Straight Teeth: A Video Explanation"

A video from Ted-Ed explains why early humans had naturally straight teeth and we don't. The prevailing theory is that millions of years ago, when humans were hunter-gatherers, their teeth had to work extra hard to grind down seeds, fruit, meat, etc., and make them digestible. When humans began incorporating tools, food was broken down before it even entered the mouth. It only became more refined and easier to chew with the introduction of agriculture, followed by the innovations of the Industrial Revolution. Over time, jaws have reduced in size much more quickly than our teeth have, leading to overcrowding and some unique dental arrangements.