Final answer:
The migration and evolution of horses from North America to Asia and Europe is an example of Secular Migration. This long-term migratory process is reflected in the fossil record showing the adaptation of horse species to changing environments.
Step-by-step explanation:
Horses originated in North America and then migrated to Asia and Europe, evolving over many generations into the species we see today. This process illustrates Secular Migration, a type of migration that occurs over a geologic time scale, resulting in the evolution and adaptation of species to new environments.
The fossil record of horses in North America is especially rich and shows a clear transition of species from a forest habitat to a prairie environment, with changes in anatomy such as teeth shapes and leg structures for grazing and rapid movement, necessary for escaping predators. The migration and subsequent evolution of horses are detailed in an array of fossil evidence, including that of Eohippus, Mesohippus, Hipparion, and modern-day Equus.
The reintroduction of horses by Europeans during the colonial period dramatically impacted the cultures of Indigenous peoples in the Americas, further showcasing the profound effects of animal migration and evolution.