At first glance, donkeys and horses may look similar, but there are so many differences between them – donkeys are not just small horses with big ears!
What's the difference between a horse and a donkey?
Are donkeys and horses related?
All donkeys and horses evolved from a common ancestor, Dinohippus, who roamed the plains of North America some 10 million years ago. Since then, they have evolved into very different animals. As a result of this long evolution, donkeys are closer ancestors to zebras than they are to horses.
Are there any wild horses?
Przewalski’s horses are considered to be the only true wild horse species left in the world, as the other ‘wild’ horses today, such as the American mustang or Australian brumby, are feral horses descended from domesticated one. These horses have adapted to various marginal habitats, but because they are from a domesticated species, they are considered feral or free-roaming, rather than wild.
Are there any wild donkeys?
In contrast, there are still three distinct species of wild assess. The African wild ass (Equus africanus) and the Asiatic wild ass (Equus hemionus) or onager, and the kiang (Equus kiang). The are 12 different subspecies of wild ass within these groups. Interestingly, Asiatic assess have never been domesticated.
The African wild assess are all considered to be Critically Endangered with only a few hundred to a few thousand left in the wild when last recorded in the 1990s. In the late 1990s wild kiang numbers were estimated to be between 60,000 and 70,000.
When were horses and donkeys domesticated?
Domesticated donkeys’ ancestors, Nubian and Somali wild asses, originated in North Africa. The domesticated horses’ ancestors most likely originated from Asia. Both donkeys and horses seem to have begun the process of domestication around the same time, about 6, 000 to 8,000 years ago. Domesticated donkeys were used in ancient Egypt 4,000 to 6,000 years ago before their use on trade routes spread them across the world. Both horses and donkeys were reintroduced to the Americas by European explorers in the 15th and 16th centuries.
Donkey vs horse: natural habitat and diet differences
Horse ancestors evolved on the temperate regions of Eurasia, while domestic donkeys originated from the African wild ass in semi-arid regions of Northeast Africa. The different evolutionary habitats result in horses being grazers, who are adapted, to live in grassy areas with readily available water sources. Horses are more adapted to the temperate climate of the UK and Northern Europe. In contrast to the grassy plains of Asia, the donkeys’ ancestors evolved in sparse arid environments, and so donkeys are browsers, who are better suited to eating rough vegetation and browsing on shrubs and bushes. Donkeys are also better adapted to hotter, drier climates.
Horses vs donkey: herd structure differences
Horses evolved on grassy plains, and as a result, the increased availability of food meant horses formed larger bands of mixed-age and sex animals. They have home ranges which they may share with other bands of horses, and they are not territorial. There is less competition for food, and stallions try to gather a stable herd of mares to breed with. Stallions without a herd of their own will join together to form bachelor bands.
Social behaviour of domesticated donkeys evolved from their ancestors’ needs to adapt to the sparse arid environment with little water in North Africa. An African wild-ass stallion will establish and hold a territory in the hope of attracting female donkeys. This is why, even today, domestic donkeys can still be territorial. In the wild, females tend to live alone or in small groups of two or three animals, perhaps including a young foal. Mares wander arid habitats in search of enough food to sustain themselves and their foals, and they access water sources where stallions have made their territories.
In contrast, in Asia where food and water is often more available, Asiatic asses’ herds might reach 80 animals in the non-breeding season. And in the breeding season, herds form in a similar way to feral horses.
How does a donkey's behaviour differ to a horse's behaviour?
Due to the donkeys' evolutionary ancestry, their body language tends to be more subtle and therefore, more challenging to read than a horse's.
When scared, donkeys may move a short distance before turning to face whatever is worrying them. This gives donkeys the appearance of freezing before choosing to use their flight or fight response. Donkeys have a great sense of self-preservation and show less obvious signs of pain and discomfort. These behaviour traits mean the donkeys' subtle body language is often missed or incorrectly labelled as stubbornness.
Horses rely much more on their flight mechanism as a means of survival. Living in herds means horses rely on the use of very visual body language to communicate to the rest of the herd.
The differences in the use of body language also affect the way each species displays pain. Donkeys are considered more stoic and show less obvious signs of pain than horses, who are more obvious in their reaction to similar pain levels.
Donkeys show much more territorial behaviour than horses. Donkeys will often chase and attack small stock such as sheep, goats or dogs that enter their field.
Body language plays a massive role in the day-to-day life of almost all animals, including humans. Donkeys and horses use the same body language signals to communicate their emotional states and warn others of their intentions. Contrary to common belief, the swishing tails, ears back, and foot stamping behaviour of horses and donkeys are all designed to avoid conflict.
Horse vs donkey: anatomy
Horses’ coats contain natural oils that make it more water resistant, whereas donkeys will need to seek shelter out of the rain. In fact, research shows that while horses can cope well with gloomy weather, most donkeys seek out shelter under a light breeze, if it starts to rain, or when temperatures drop below 14 degrees.
Donkeys’ feet are a different shape being more upright and narrower than the rounder feet of horses. Donkeys have a tendency to grow long and twisted hooves if they are not trimmed regularly. Horses’ hooves appear more brittle, with overgrown hoofs breaking off more readily than donkeys.
Donkeys have a lower body temperature range (36.5-37.8 °C) than horses (37.2-38.5 °C).
Why do donkeys have such large ears?
Finally of course, there are the donkeys’ larger ears. These large ears appear to be an adaption to the African wild assess’ warmer climate, where larger ears can be used to help control the donkeys’ temperature. Horses and Asiatic asses have smaller ears. This is much the same as the larger ears of the African elephant compared to the Asian elephant.
Horse vs donkey: vocal differences
Donkeys have seven vocal sounds, with the loudest being the donkeys’ distinctive bray. Each donkey’s bray is individual and designed to be heard over long distances in the wild. Horses don’t bray, relying instead on their higher-pitched whinny to communicate in their herd.
What is the difference between a mule and a hinny?
Donkeys and horses can interbreed. A mule is the result of a donkey stallion mating with a female horse. Hinnies are less common and result from a horse stallion mating with a female donkey.
Mules and hinnies are a mix of the anatomy and behaviour of the donkey and horse parents. Mules are commonly used as working animals. Due to their hardiness and strength, mules have been used in large numbers in most human conflicts over the last 200 years, including World War I and World War II.
Main image: Getty Images
Ben Hart is the Senior Lead of the Behaviour & Human Behaviour department at The Donkey Sanctuary