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
The Language of the Birds food and clothing and asked what he wanted. The father asked him to take him as a servant. Ivan told him that the song of the nightingale had come true, and provided for his parents. A similar tale is attached as a legend to Eilean Donan Castle in Scotland, in which a lord gave his son the power to speak with birds by making his first sip be from a raven's skull. There is a Portuguese tale collected by Francisco Adolfo Coelho, "The Little Boy and the Moon," that unfolds in a fashion largely analogous to "The Language of the