Chickens in the American barnyard are long descended from domesticated jungle fowl of India and Asia going back beyond 4000 years. Although chickens are the most common birds, North American farms often also include turkeys, ducks, geese, guinea fowl, and occasionally squab. Present-day classes of chickens are based on origin: English, Asiatic, American, Mediterranean, and European, with English and American breeds the most common on American farms. Common breeds such as New Hampshire, Plymouth Rock, Rhode Island Red, and others were developed for both good egg production and quality meat. Healthy birds can produce an egg almost daily for much of the year and are large enough to be harvested for meat after three months. Farm birds are most often fed kitchen scraps and allowed to graze for themselves, providing a farmer and his family not only for their own needs but often a pocket income as well.