What is a bird’s egg tooth? How is it used when it hatches from its egg?
When a chick is ready to hatch out of its egg it must break the egg shell.
The chick has a small, sharp, white, projection on the tip of its beak, called an egg tooth.
It is not really a tooth. It is a hard piece of the beak’s tip.
It uses the egg tooth to break the membrane (thin skin) inside the egg, and then to tap on the egg shell until it breaks.
It takes hours and sometimes days for the hatching chick to break the egg.
The chick usually loses its egg tooth within a few days after hatching. The petrel loses its egg tooth after about 20 days.
Generally, the egg tooth just drops off.
Photographer: Martina Nicolls
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