green lake


Fossil Dawn Horse (Protorohippus venticolus, Early Eocene) - Fossil Lake, Kemmerer, Wyoming

One of  two horse skeletons discovered in Wyoming’s Green River Formation. The five fish embedded in the slab are a testament to the rare circumstances that led to this land animal being buried in the middle of Fossil Lake. The details of this intriguing occurrence remain a mystery. One suggestion is that the horse was fleeing a predator and it made its way to shallow water, but was swept away into to the middle of the lake where it eventually drowned.

Protorohippus venticolus is the most primitive species of the Equidae family. This diminutive horse was only 20 inches (50 cm) tall at the shoulders and about two feet (60 cm) long as an adult. Interestingly, it had four padded hoofed toes on its front legs and 3 on its long hind legs. Its grinding teeth were well-suited to a diet of fruit and leaves, which were abundant in the subtropical climate that it inhabited.