babirusa
Emily K on April 15, 2007
Babirusas might be the most extreme case of sexual burden of all. Males have tusks that grow from their lower jaw until they pierce the roof of his mouth, and continue to grow towards the forehead. If they grow long enough, they can even pierce his skull and kill him. Male babirusas use their tusks to fight with each other over the right to mate with females.
Babirusas have the only known natural puncture in animals, which medical researchers are trying to study. When a babirusa’s tusks puncture his mouth, the holes do not get infected. The researchers hope to fully discover how it works so they can apply it to human medical research.
zoopzoopzoopzoop987 at 2:41PM, Nov. 22, 2009
... I've always wondered WHY the tusks would keep growing, eventually into the head. Long tusks to attract females, I can understand, but long enough to kill them? You'd think it'd be an evolutionary step backwards, almost. o_o;