How many animals species have been domesticated?

The exact number of domesticated animal species varies depending on the definition used. However, according to estimates by the Food and Agriculture Organization (FAO) of the United Nations, there are around 40 species of mammals and birds that have been domesticated worldwide for various purposes such as food, transportation, companionship, and research.

These domesticated species include common animals like cats, dogs, cattle, goats, sheep, pigs, camels, horses, donkeys, chickens, ducks, geese, and turkeys. However, there are also lesser-known domesticated species such as water buffalo, yaks, llamas, alpacas, reindeer, rabbits, cavies (guinea pigs), deer, ostriches, and emus. Additionally, some species have multiple breeds or varieties that have been developed through selective breeding. When considering specific breeds and variations, the total number of domesticated animal species could be much higher.