Reproduction, Babies, and Lifespan
In the wild, these animals have polygynous mating systems. One adult male, or stallion, would herd a group of adult females, or mares, during the mating season. Stallions defend their mares from other males in the area in an intensive process similar to rutting in deer species. Domestic horses, however, are more selectively bred. This type of artificial selection has given rise to the many different breeds, sizes, uses, and colors of the modern-day horse.
An unborn foal spends about 11 months being carried by its mother. A baby that has not yet been weaned is called a foal and usually can stand and run a short time after it is born. After it is weaned from its mother, a young female is known as a filly, and a young male is known as a colt. A full month after one foal is born, a mare can be mated again. However, horses that are castrated or spayed are known as geldings and cannot have offspring.
Domestic horses live anywhere from 25 to 30 years on average. However, the oldest recorded animal died in 2007 at the remarkable age of 56 years old. The longest-living wild horse is believed to be 36 years old before its death. Someone who works with these animals can tell their age by the pattern of tooth wear.