Chicken breeds number in the hundreds, as farmers and breeders have selected for size, egg color, meat, growth, and many other factors. A hen is a female chicken over one year, and a bantam is a chicken that’s intentionally bred smaller, often for backyard farms.
History
From the wild red jungle fowl of southeast Asia, which are relatives of pheasants, chickens were domesticated some 6000 years ago or more. All domestic chickens, then, are the same species, but there are now hundreds of distinct breeds, each the result of geography and selection. Chickens were initially domesticated for sport, but their usefulness as layers and broilers led to a broadening of the breed, as specialized selections were made for meatier chickens and more consistent layers. Chickens have also been bred for egg size, weather tolerance, feather color, egg color, and personality. Bantam breeds have existed for at least 500 years, probably much longer. There are true bantam breeds that are naturally smaller, and there are also bantam versions of established breeds. Recently, bantams have exploded in popularity due to the rise of backyard homesteading and urban farming.