In the Old World, Europe, Asia and Africa, where animals have been domesticated for millennia, donkeys stand out as exceptionally wild and mean. Donkeys were domesticated in 5,000 BC, a thousand years before the horse, which was about 4,000 BC, and have about the same reproductive time scale as horses. The question would become why are horses mild-mannered with humans and donkeys still mean towards us when both have been associated with humans for so very long?
A parallel case is with dogs and Silver Foxes. Dogs were domesticated about 15,000 BC and Silver Foxes only over the last one hundred years using careful artificial selection processes based on human-avoidance-distance. The techniques for the human selection of dogs/wolves is unknowable in detail, but it did require their living in close proximity to humans. Humans would only tolerate and feed animals they liked so there would have been a drift toward the dog-like traits we now prefer. Those early humans might not have been selecting for dogs they liked so much as driving away or killing those they didn’t like. At some point humans developed intellectual verbal selection techniques, such as, Like breeds like, and for plants, Bury the best.
Over the huge span of time that dogs have lived with humans, they have become very friendly towards us. This is especially true if raised in a canine-friendly human environment such as Cesar Millan promotes. Dogs are more friendly towards humans than humans are toward one another if both species are consistently treated in a friendly manner. The difference between a man and a dog is that a dog will not bite the hand that feeds him. Or, as Mark Twain more eloquently said it, If you pick up a starving dog and make him prosperous, he will not bite you. This is the principal difference between a dog and a man. The Russian Silver Foxes have become fully domesticated through careful breeding for domestication, mostly in the last fifty years. Unexpectedly, during this time they have developed several non-intended secondary characteristics, such as mottled fur, raised tail and tail wagging. This is possibly an infantile trait of the common ancestors of both dogs and foxes. It appears that our domesticated animals have unknowingly been bred for ancient infantile traits.
Why haven’t donkeys become more friendly towards humans? Donkeys have been exposed to humans since about 5,000 BC in Egypt and yet they are still infamously hostile to humans. Donkeys are not domesticated animals; they are better characterized as wild animals kept in captivity; they are slaves to humans and not companions. Horses were domesticated about the same time and when raised in the presence of humans are comfortable with us. Not so with donkeys. Donkeys hate humans, always have and always will – at least in their present genetic form. But, one wonders, if they were subjected to the same genetic selection pressures as the Silver Foxes might they become more friendly, or perhaps not. It might be dependent upon their ancestors’ infantile behavior which is still latent in their genes, such that even when bred for infantile behavior they will still be ornery. Perhaps there is something naturally antisocial about young donkeys which prevents their being domesticated. Naturally social herd animals are easy to domesticate because they are tolerant of other accepted individuals, so that friendly behavior is genetically natural to them. Not so with donkeys.
There is another possibility. The people who own donkeys are presently poor and the class of people who own them have been poor for the last 7,000 years. These animals are true beasts of burden, and the humans who own them are themselves the beasts of burden of human society. Because of their very limited resources, these people have not had the luxury of choosing which donkeys are to be bred to which and for what purpose, other than that they be healthy and strong, and perhaps the wild genes are necessary to maintain those qualities in top form. Most domestic animals are noticeably weaker in every way than their wild cousins. Donkeys are closely enough related to horses that they can be interbred, and so they are. The animals of these unions are called mules and they are highly valued because they possess the strength and endurance of the donkey and some of the size and docility of the horse. They are commonly used as pack animals in mountainous regions where wheeled vehicles can not go.
Perhaps what we see in a donkey is the end result of the forces which Adam Smith and Thomas Malthus were discussing in their philosophies of living things and social groups. Working people are driven by their reproductive propensity to over procreate, to have too many people for the work at hand. Thus, some of them must go hungry and starve, and only the most vigorous survive to reproduce. Similar forces are at work concerning the donkey, where the economy of their usage demands vigorous health, maximum strength and endurance relative to consumption of food, and the social qualities of docility are not valued and are not bred for.
Donkeys and recurrent famines among workers are the victims of human society’s success.