If you look closely at the teeth in your mouth, you’ll find that you have four pointy canine teeth in between your incisors and premolars. But have you ever wondered why these teeth are the way they are?

Pro tip: they’re not for vampire-esque activities and they’re not for tearing meat as other predatory mammals with similar pointy teeth would use them for. Instead, much like our close relative the gorilla, scientists think they exist because they once played a role in mating in our primitive ancestors.

Modern-day gorillas have much larger canine teeth than humans, and we can actively observe how they use them to compete with one another for mating rights with a female. Generally, the male with the largest canine teeth wins the fight.

Obviously, modern-day humans don’t do this – or least they don’t anymore. It’s hard to say for sure whether our primitive ancestors partook in these canine tooth-centric brawls to win over a mate, but skull remnants of the first humans, Ardipithecus ramidus, reveal that our ancestors sported larger canine teeth than we have today. Mere happenstance? – Eh, that seems unlikely.

Modern humans continue to exhibit smaller and smaller canine teeth over time, which directly correlates with the fact that we don’t really need them anymore. Nevertheless, men generally have longer and sharper canine teeth than women, which offers strong evidence for the proposed theory.