The horse is a domesticated one-toed hoofed mammal. It belongs to the taxonomic family "Equidae" and is one of two extant subspecies of "Equus ferus". The horse evolved over the past 45 to 55 million years from 'Eohippus', a small multi-toed creature, into the large, single-toed animal of today.

Depending on the breed, management, and environment, the modern domestic horse has a life expectancy between 25 to 30 years. Uncommonly, a few animals live into their 40s.

Horses have 64 chromosomes (DNA molecules). The horse genome was sequenced in 2007. It contains 2.7 billion DNA base pairs, which is larger than the dog genome, but smaller than the human genome or the bovine genome.

More Info: