Animal genetic resources for food and agriculture crop and livestock species in the early neolithic time period changed our human evolution and lifestyles. This ability to control food production led to major demographic, technological, political and military changes. Consecutively, thousands of years of natural and human selection, genetic drift, inbreeding, and crossbreeding have contributed to the diversification of animal genetic resources and increased the variety of environments and production systems that livestock keeping takes place. Relatively few species have been domesticated; out of the world's 148 non-carnivorous species weighing more than 45 kg, only 15 have been successfully domesticated. The proportion of domesticated birds used for food
Animal genetic resources for food and agriculture of animal genetic resources includes diversity at species, breed and within-breed level. Known are currently 8,800 different breeds of birds and mammals within 38 species used for food and agriculture. The main animal species used for food and agriculture production are cattle, sheep, goats, chickens and pigs. In the livestock world, these species are often referred to as "the big five". Some less-utilized species include the dromedary, donkey, bactrian camel, buffalo, guinea pig, horse, rabbit, yak, goose, duck, ostrich,partridge, pheasant, pigeon, and turkey. The history of animal genetic resources begins about 12,000 to 14,000 years ago. The domestication of major