Why do we have wisdom teeth?

Answer: Evolutionary leftover from diet

Backup teeth in case of loss — Wrong. While extra teeth seem like backups, wisdom teeth are actually evolutionary leftovers that often don't fit properly in modern jaws.

Evolutionary leftover from diet ✓ — Correct! Wisdom teeth are third molars that were useful to our ancestors who ate coarse, tough foods like roots, nuts, and raw meat. As human diets changed and jaws became smaller through evolution, these teeth often don't fit properly and may need removal.

Mark of reaching adulthood — Wrong. Wisdom teeth aren't markers of adulthood. They're evolutionary remnants that typically erupt in late teens/early twenties when jaw growth is complete.