Ever wondered why testicles are dangling in a nutsack? It would make much more sense to pack such a delicate thing (or rather: things) on the inside of a body, where it’s protected by muscle tissue and such. But no, the very tender part of a male’s body is positioned outside his body, unprotected from the elements, and in a highly vulnerable place. Why? ’cause it’s colder there!

Sperm develops best several degrees below body temperature. And it stays alive a lot longer once activated at lower temperatures. And that’s why they’re excluded from the body and stored on the outside. Now you know!