The process of domestication of animals and plants allowed humans to become more settled and their populations to grow. Animals kept for milk and dairy products were far more productive than those simply killed for meat. During their lifetime their manure could be used as fertiliser, and their strength, in the case of cows and buffalo, could be harnessed to pull ploughs to allow cultivation of a far wider area. Horses, donkeys and camels were kept mainly to transport goods and people; they enabled the spread of human settlement more quickly, and over a wider area than would hitherto have been possible. The speed and agility of horses in particular gave their riders an advantage in warfare over peoples who lacked them.
But few animals – especially large ones – have become truly domesticated. The dog was probably the first, c.10,000 bc, in southwest Asia, China and North America. Of the herd animals, goats – hardy, sure-footed and omnivorous – were domesticated in the Zagros mountains of south-west Asia at least 10,000 years ago. Sheep and pigs – which were also found in a wide range of locations, including central Europe, Italy, northern India, China and Southeast Asia – followed not long after. Cows were domesticated around 6000 bc in south-west Asia, India and North Africa; and horses, donkeys and water buffalo by 4000 bc. Llamas and alpacas in South America, Bactrian and Arabian camels, reindeer, yak, gaur and banteng are the only other species considered to be genuinely domesticated, and it appears that the process of domestication of large animals was completed more than 4,500 years ago.
Other creatures, such as elephants, cheetahs and bears, though kept for hunting or other purposes, were tamed rather than domesticated. Both historically and more recently, there have been attempts to herd or farm other species, such as zebra, moose and bison, but they have not proved enduring or economically viable.
Sub-Saharan Africa, with its host of magnificent wildlife, has never produced a domesticated native species. Why is this?
Three main factors influence the practicalities of animal domestication: the cost of rearing the animal, its rate of growth and its ability to reproduce in captivity. A large carnivore, such as a lion or tiger, would be prohibitively expensive to raise for meat, while an animal with a similar developmental and lifespan to humans – such as an elephant – would take too long to reach adulthood. And creatures with complicated courtship rituals or that require specialised circumstances to breed are unlikely to be successfully domesticated. The other requirements are a calm, non-violent disposition and a social or herd structure with a clear hierarchy. While many creatures have some of these characteristics, they usually have a fatal flaw – in antelope the tendency to panic, in zebra sheer irascibility – that makes them impossible to domesticate.