Egg tooth
（重定向自Epidermal Tooth）
![A Senegal parrot chick at about 2 weeks after hatching. The egg tooth is near the tip of its beak on the upper mandible.](/Images/godic/202501/11/Poicephalus_senegalus_-egg_tooth_-two_weeks-21July074850.JPG")
![Borneo short-tailed python (Python breitensteini) hatching with egg tooth visible](/Images/godic/202501/11/Python_egg_tooth4850.jpg")
![A red-eared slider hatchling with an egg tooth.](/Images/godic/202501/11/Egg-tooth24850.jpg")
In some egg-laying animals, the egg tooth is a small, sharp, cranial protuberance used by offspring to break or tear through the egg's surface during hatching. It is present in most birds and reptiles, and similar structures exist in monotremes, Eleutherodactyl frogs, and spiders.