A baby chicken is born from an egg that comes from inside the mother hen.
The chick that is inside the newly laid egg is a tiny cell called a “germ cell” that will develop into the baby chicken.
If you look closely at the yolk, or yellow part of a hen’s egg, you can see the germ cell as a light-colored, pinhead-sized dot on the top of the yolk.
The hen sits on the egg and keeps it warm. While she sits, the germ cell divides into other cells that form all the parts of the baby chick. The chick grows until it is so big that it fills the whole egg.
When the chick is ready to hatch from the egg, it cracks the shell with its sharp beak and wiggles out.
All baby birds hatch from eggs the same way that the baby chickens come into the world.
Photo courtesy: lancaster