Title: Horse Content: thumb|Horse riding Horses are a diverse group of animals of the family Equidae. They are herbivores, which means they eat grass and other plants. Some plants are dangerous for them, like ragwort, lemongrass (oil grass) and sometimes acorns. The standard horse is the species Equus caballus. It was domesticated from wild horses by humans at least 5000 years ago. They are large, strong animals and some breeds are used to pull heavy loads. Racehorses can gallop up to 30 miles an hour. A male horse is a stallion, and a female horse is a mare, while the general term for a young horse is a foal. A young female horse is a filly, and a young male horse is a colt. A castrated horse is a gelding. Horses have hooves which need protection by horseshoes from hard or rough ground. A horse is related to the rhino and tapir in the order Perissodactyla. == Early horses == thumb|200px|A group of horses The evolution of horses has been well studied. Fifty million years ago, there were no horses as we know them now. Of the earliest fossil horse, the North American one is called Eohippus, and the Eurasian one is called Hyracotherium. Both were small animals: Eohippus was the larger of the two at twice the size of a terrier dog. Many changes occurred between those little animals and today's horses. These changes are best explained as adaptations. To its changing ecological niche, from a small forest-dweller eating nuts and fruit to a more significant forest browser eating leaves and small branches. Finally, the modern horse is a grazer on open grassland, with different teeth, legs for running, and a much larger size. Significant changes happened in the mid-Miocene when the climate cooled and grassland replaced forests. This change continued, and several groups of mammals changed from browsers to grazers. == Horses and humans == thumb|200px|Horses pulling a plough Horses have been domesticated for at least 5000 years. Humans have used them in many different ways for travel, work, food, pleasure and show. Cavalry horses were used in war until the mid-20th century. They are used for riding and transport. They are also used for carrying things, pulling carts, or helping plough farmers' fields in agriculture. People have used selective breeding to make more giant horses do heavy work. Some people keep horses as pets. Today, horses are mainly used for entertainment and sports. They are also still used for work and transportation in some places. Horses are used in equestrianism, and equine sports such as cross-country, show jumping, and other events. Show jumping, cross-country, and dressage are Olympic sports. "Equus" is the old Latin word for horse. == Other uses of horses == Horsehide is a rugged leather made from the skin of horses. Horsehair is used to create a stiff fabric. Horsehair can also be used as a stuffing for furniture. Horsehair can be mixed with plaster to make it strong. People can use horse bones to make gelatin for food. People can also use the bones to make glue. Animal glue is still preferred by some woodworkers. Horses are used all over the world to carry people and pull carts. Big cities use them to help police watch and protect people in crowds. == Mare == A mare is a female horse. Other female equines are also sometimes called mares. Before the mare's third birthday, the mare is called a filly. When a mare wants to mate, the mare is called in heat. This part of the oestrous cycle lasts about three weeks. Mares are more prone to being temperamental. Some people would call this being "mare-ish." == Horse breeds == These are some well-known horse breeds among the hundreds that exist: == Related pages == * Horse riding – sports with horses ** Horse racing * Pony – for little horses * Quagga * Przewalski's horse * Donkey (Ass) * Mule * Zebra