Prehistoric fossil records indicate that Equidae (what is now known as the horse) underwent the majority of its evolutionary history within the last 60 million years.
This first horse was given the name Hyracotherium in Europe and Eohippus in America.
Eohippus was a browser, feeding on soft leaves and despite its short legs was able to move around between marsh land and lush woodland.
Due to its soft diet it did not require the use of large molars which were not evident at this early stage of evolution.
Eohippus had small sharp incisors ale to snip of succulent foods, a small skull and forward pointing eyes with only 6 small triangular shaped cheek teeth along the arcade.
Over the course of the succeeding 50 million years the climate changed dramatically and the onset of the ice age brought about a change in landscape and available vegetation. During this period of change eohippus's descendants adapted and evolved to keep up.
The now more open, drier landscape brought about many changes. For survival in this time animals were required to flee from larger land predators. The more successful evolutionary descendants evolved for these purposes.
Their limbs grew longer (relative to body size). Their five toes reduced to a faster single digit encased in a hoof for protection. Feeding patterns changed due to an increased predator threat and environmental influences. They became nomadic, always on the move. Living in herds for greater protection. Grazing from grassy planes for extended periods of time
The anatomy of their head and teeth had also evolved
-They now grasped the shorted course grasses that had become their stable diet, with their lips first before using a pincer action with their incisors.
-The head had elongated to accommodate for larger squarer molars needed to grind the more course grasses of the time
-The larger skull size also saw a change in the position of the eye sockets to a more laterally situation. This enabled a wilder field of vision to allow for continuous grazing whilst watching for predators.
These changes happened gradually but for the purposes of survival and have given us the horse we know today, Equus.
Tammy is a passionate horse rider who wishes to promote the best ways to be looking after horses. Tammy works part time for equinedentistryblades.co.uk who specialise in equine dentistry equipment as well as horse speculum and equine dentistry supplies. For more details, please visit http://www.equinedentistryblades.co.uk
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