Horse

Domestication of the Horse

Horses began appearing in cave art as early as 30,000 BCE, but these were truly wild horses, and were probably hunted for meat. How did the transition from prey species to domestic species come about?

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The evolution of the horse from the very early (around 55 million years ago) Hyracotherium or eohippus to the wild equids listed below, is well understood in comparison to our understanding of the evolutionary succession of most animals. By natural selection, the toes of early horse ancestors were reduced to the single central toe which is the hoof of the modern equine. Vestiges of other toes remain as the splint bones, the callous-like "chestnuts" on the inner sides of all four legs, and the "ergots" hidden in the hair of the underside of the fetlock joint. Rare instances of modern horses with true extra toes have been cited by evolutionary biologist Stephen Jay Gould as evidence that minor genetic mutations can reintroduce ancestral features (in his 1983 book Hen's Teeth and Horse's Toes).

In nature, horses are prey animals. Their natural tendency is to flee from danger, though they'll fight if cornered. Their eyes are placed to the side of the head, giving them a wide view while grazing. Even domesticated horses are easily startled and must be carefully introduced to strange objects and situations to be able to ride them safely.

Horses live in family groups in primarily grassland habitats. These normally consist of a mature stallion, his harem of mares, and the mares' offspring. Once young males reach breeding age and begin to attempt to breed mares or challenge the herd stallion, they are driven out of the herd and form "bachelor bands" with other young stallions. It's usually not until a stallion reaches 7 or 8 years old that he stands a real chance at acquiring mares.

An alpha mare dictates the direction in which a family herd travels, while the stallion brings up the rear, "herding" his family. Recently, researchers have observed there seems to be a form of democracy among horses. For instance, if the majority of the herd decides it's time to stop and eat, the whole herd will stop and eat.

Horses graze in a field near London, England
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The Tarpan, Equus caballus gmelini, became extinct in 1880. Its genetic line is lost, but a substitute has been recreated by "breeding back", crossing living domesticated horses that had features selected as primitive, thanks to the efforts of the brothers Lutz Heck (director of the Berlin zoo) and Heinz Heck (director Tierpark Munich Hellabrunn). The resulting animal is more properly called the Wild Polish Horse.

The Icelandic horse (which is pony-sized but is referred to as a horse) is an interesting breed from a historic and behavioural point of view. Introduced by the Vikings into Iceland, they have not been subject to the selective breeding that has taken place in Europe from the middle ages until now, giving us a picture of what horses looked like and behaved like in those times. The Icelandic horse has a four-beat gait called the Tolt, which is equivalent to the Rack exhibited by several American gaited breeds.

Horses are usually distinguished from ponies purely according to size: a horse stands 14.2 hh (58 inches, 1.47 meters) or higher, a pony is an adult equine less than 14.2 hh. Thus, normal variations can mean that a horse stallion and horse mare can become the parents of an adult pony. There is however a distinct set of characteristic pony traits that evolved in northwest Europe and further evolved in the British Isles, muddying the issue of whether "pony" should be used to describe a size or a type. Several small breeds are called horses or ponies interchangeably, including the Icelandic, Fjord, and Caspian. Breeders of miniature horses favor that name because they strive to reproduce horse-like conformation in a very small size, even though their animals are undeniably descended from ponies.

• horse - adult equine of either sex over 14.2 hh (58 inches, 1.47 meters)
• pony - equine 14.2 hh or less (58 inches, 1.47 meters)
• mare - adult female horse
• stallion - adult, uncastrated male horse
• gelding - adult, castrated male horse
• foal - infant horse of either sex
• filly - female horse from birth to sexual maturity (about 24 months)
• colt - male horse from birth to sexual maturity (about 24 months)

A vocabulary of specialized words relating to horse anatomy

• withers - the highest point of the shoulder seen best with horse standing square and head slightly lowered. The withers are formed by the tops of the two shoulder blades and the space between them.

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The Origin of Modern Horse Breeds

There are several schools of thought on how this range of size and shape came about. These schools grew up reasoning from the type of dentition and the horses' outward appearance. One school, which we can call the "Four Foundations" is that the modern horse evolved from two types of early domesticated pony and two types of early domesticated horse; the differences between these types accounts for the differences in type of the modern breeds. A second school is the "Single Foundation"--that there was only one breed of horse domesticated, and it diverged in form after domestication by human selective breeding (or in the case of feral horses, ecological pressures). Finally, there are those geneticists who are evaluating the DNA and mitochondrial DNA to construct family trees.

The modern landscape of breed designation is a complicated one. Some breeds have closed studbooks; a registered Thoroughbred or Arabian must have two registered parents of the same breed, and that is the only criterion for registration. Other breeds are open to limited infusions from other breeds -- the modern Appaloosa for instance must have at least one Appaloosa parent but may also have a Quarter Horse, Thoroughbred, or Arabian parent and must also exhibit spotted coloration or else be denied full registration. Still other breeds, such as most of the warmblood sporthorses, require individual judging of an individual animal's quality before registration or breeding approval.

The list of horse breeds provides a partial alphabetical list of breeds of horse extant today, plus a discussion of rare breeds conservation.

Racing in all its forms

• Dressage ("training" in French) is the progressive training of the horse to a high level of impulsion, collection, and obedience. It originated in the military and artistic equestrian academies of Europe and became an Olympic sport in 1912. Dressage competition levels start with the basic training of a young horse and advance in small steps to the highest level, called "Grand Prix." At each level the horse and rider must perform a test of gaits and figures. A judge grades each specific movement as well as overall impressions of the rider's and horse's performance. There is also a tradition of purist, noncompetitive "classical" dressage, which is pursued for its own joy and beauty.

• Show jumping is a timed event judged on the ability of the horse and rider to jump over a series of obstacles, in a given order and with the fewest refusals or knockdowns of fence rails, which for safety are set in shallow cups. At the Grand Prix level fences may be as much as 6' tall.

• Eventing, combined training, horse trials, "the Military," or "the complete test" as its French name translates, puts together the obedience of dressage with the athletic ability of show jumping, the fitness demands of a long endurance phase (aka "roads and tracks") and the "cross-country" jumping phase. This event has its roots as a comprehensive cavalry test requiring mastery of several types of riding. Cross-country riding at the highest levels can be especially dangerous to horses and riders, as the obstacles are large, technically challenging, and solidly built.

• Polo originated in Asia around 2000 years ago and became popular with 19th century Britons when they were exposed to this challenging horseback team sport in India. The game is divided into periods called "chukkas" and riders score by driving a ball into the opposing team's goal using a long-handled mallet. It has remained a sport of the rich because of the expense of maintaining an adequate string of "ponies" -- a rider needs to swap tired horses several times over the course of the fast-paced game.

• Huntseat riding is the show discipline derived from the English foxhunting style. In the modern show ring hunters show "on the flat" at the walk, trot, and canter, and "over fences" where unlike show jumpers they are judged on the rider's good position and the horse's smooth performance. A good show hunter is safe, willing, and careful over fences.

• Saddleseat, Park, or English Pleasure riding is a uniquely American discipline developed to show to best advantage the extravagantly animated movement of high-stepping gaited breeds such as the American Saddle Horse and Tennessee Walker. Arabians and Morgans are also commonly shown saddleseat in the US.

Western riding

These multiple work-needs mean that different tack must be used, most notably a curb bit (usually with longer bars than an English equitation curb or pelham bit would have) which works by leverage, long split reins (the ends of which can serve as an impromptu quirt) and a special kind of saddle. The Western saddle has a very much more substantial frame (traditionally made of wood) to absorb the shock of roping, a prominent pommel surmounted by a horn (a big knob for snubbing the lasso after an animal has been roped), and, frequently, tapaderos ("taps") covering the front of the stirrups to prevent the cowboy's foot from slipping through the stirrup in an accident so that he might be dragged behind a frightened horse. The cowboy's boots, which have high heels of an uncommon shape, are also designed specifically to prevent the cowboy's foot from slipping through the stirrup.

Competitions exists in the following forms:

• Western pleasure - the rider must show the horse in walk, jog (a slow, controlled trot), trot and lope (a slow, controlled canter). The horse must be under control with minimal force being directed through the reins and otherwise with minimal interference from the rider.

• Reining - considered by some the "dressage" of the western riding world, reining requires horse and rider to perform a precise pattern consisting of canter circles, rapid "spins" (a particularly athletic turn on the haunches), and the sliding stop which is executed from a full gallop.

• Cutting: more than any other, this is the event which highlights the "cow sense" prized in stock breeds such as the Quarter horse. The horse and rider select and separate a calf out of a small group. The calf then tries to return to its herdmates; the rider loosens the reins and it's entirely the horse's job to keep the calf separated, a job the best do with relish, savvy, and style. The cutter is awarded points by a jury.

• Team penning: a popular timed event in which 3 to 5 marked steers must be selected out of a herd and driven into a small pen by a team of 3 riders. The catch is that the gate to the pen cannot be closed till all the cattle (and only the intended cattle) are inside.

• Trail class: in this event, the rider has to manouver the horse through an obstacle course in a ring. Speed is not important, but total control of the horse is. The horses have to move sideways, make 90 degree turns while moving backwards, a fence has to be opened and/or closed while mounted, and more such manouvres relevant to everyday ranch or trail riding tasks are demonstrated.

• Barrel racing and pole bending: the timed speed/agility events of rodeo. In a barrel race, horse and rider gallop aaround a cloverleaf pattern of barrels, making agile turns without knocking the barrels over. In pole bending, horse and rider gallop the length of a line of six upright poles, turn sharply and weave through the poles, turn again and weave back, and gallop back to the start.

• Steer-wrestling: this is not allowed in Europe because of animal welfare concerns, but is done in the USA, usually at rodeo events. While riding, the rider jumps off his horse onto a steer and 'wrestles' it to the ground.

• Roping: this is also not allowed in Europe. In calf roping, the rider has to catch a running calf by the neck with a lasso, stop the animal in its tracks, rapidy dismount the horse and immobilize the calf by tying three of its legs together. This task shows the trained ability of the horse to maintain an appropriate amount of pressure on the rope after the cowboy has dismounted to tie the calf. In team roping, one horse and rider team lassos a running steer's horns, while the other brings it to the ground by lassoing its two hind legs.

• Fox hunting
• Horse hacking
• Horse show
• Rodeo
• Jousting
• Cavalry

Authoritative sources of information