Chicken

The chicken is a bird that people raise for its eggs and meat. It is the most common bird on Earth. There are more than 25 billion chickens in the world, which is about three chickens for every human. Chickens live on farms in almost every country. A male chicken is called a rooster. A female is called a hen. A baby chicken is called a chick.

Chickens were first tamed from wild birds in Southeast Asia. The wild ancestor is called the red junglefowl, and it still lives in the forests of India, Thailand, and nearby countries. People began keeping chickens at least 3,500 years ago, and maybe much earlier. Today there are hundreds of different breeds, from tiny bantams the size of a football to giant Jersey Giants that can weigh 13 pounds.

A chicken's body is built for pecking and scratching the ground. Chickens eat seeds, grass, bugs, and worms. They have a sharp beak but no teeth. Instead, they swallow small stones that sit in a special stomach part called the gizzard. The stones grind up food the way teeth would. Chickens can fly short distances, but most modern breeds are too heavy to get far off the ground.

Chickens are smarter than many people think. Studies show that chickens can recognize more than 100 different faces, both chicken and human. They can learn their names. They dream while they sleep. Mother hens "talk" to their chicks before the chicks even hatch, clucking softly through the eggshell. The chicks cluck back from inside.

Hens lay eggs even when there is no rooster around. Those eggs cannot hatch into chicks, but they are still good to eat. A healthy hen can lay around 250 to 300 eggs a year. If a hen does sit on fertilized eggs, she keeps them warm for about 21 days until they hatch.

Here is something surprising. Chickens are the closest living relatives of the dinosaurs. In 2007, scientists studied tiny bits of protein from a 68-million-year-old Tyrannosaurus rex bone. When they compared the protein to modern animals, the chicken was the closest match. In a real way, every backyard chicken is a small, feathered cousin of T. rex.

Chickens appear in stories, sayings, and holidays all over the world. Roosters are symbols of sunrise in many cultures because they crow loudly at dawn. The chicken may be ordinary, but it has a history stretching back to the age of dinosaurs.