Horse Genetics. Ernest Bailey
species of equids have been extinct in North America for thousands of years (except for zoo collections), but feral horses and donkeys are untamed, referred to as wild, and are free ranging in several locations around the world. Feral animals are descended from domestic horses and asses.
Summary
• Domestic horses belong to the family of odd-toed mammals called Perissodactyla.
• Within the family the horses are members of the genus Equus, which includes horses, asses, Asiatic asses and zebras.
• Among the differences in equid species are vastly divergent chromosome numbers. The evolution of equids entailed extensive chromosome rearrangement.
• The different species can produce viable offspring; however, they are almost always sterile due to the differences in chromosome number.
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4 The Fundamentals of Genetics
Genes behave in very predictable ways. In fact,