Wednesday, June 1, 2016

Wendy Williams - The Horse--Part II Evolution

I finally finished Wendy William's The Horse: The Epic History of Our Noble Companion. Her master work includes interviews with researchers studying wild horse behavior, organizers who successfully reintroduced the Przewalsksi or Takhi wild horse to Mongolia, scientists studying equine social behavior, and much more.

Williams writes so vividly that for the first time I read about the evolution of the horse from start to finish--a process involving continental drift, triumph of grass, climate change, plant wax at the bottom of the ocean, and much more.

Below is a photo from the 1905 Scientific American article on the evolution of the horse. It contrasts the phases of a modern horse canter (based on photographs) with how scientists of the time thought the Hyracotheium, a 4-toed horse dating from 56 million years ago in the Eocene period moved. Hyracothenium was assumed to canter like modern horses.

As Williams explains these very early horses lived in a warm, jungle- like environment in which they mushed grapes, browsed on other fodder, and scampered like rabbits. The modern horse canter was millions of years in the future. Plains covered in grass appeared and the horse grew taller, four toes became one toe,evolved to run, and developed the tough teeth needed to graze on silica-based grasses. The eyes moved closer to the top of the head as the teeth took up more room in the jaw.  Brains grew bigger to track and find more dispersed resources.

The evolution of the horse had one benefit important to mankind. As Dr. Martin Fischer, German evolutionary biologist explains, "Horses are actually the only dorsal-stable animal we have. That's why we can ride them." p. 83

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