Museum scientists have discovered nearly 500 Parahippus jaws from the Thomas Farm Fossil site, allowing study of differences between juveniles and adults. It’s important to understand how an organism changes within its lifetime before defining how a species evolves over time.
Fossil horses have been long used to study evolution. In Florida, we are very fortunate to have an 18-million-year-old sample right at the time when horses are transitioning from browsing, forest-dwelling animals to open country, grazing animals. The Thomas Farm Parahippus has thousands of specimens recording this transition. We are able to study these jaws to determine that the wear on their teeth is about 50 percent greater than those of browsing horses. That put evolutionary pressure on the species to increase the height of the crown so the animals can live longer and have more progeny.
Collection Manager, Vertebrate Paleontology
Florida Museum of Natural History
Ancient Horse Jaws (Parahippus leonensis)
From Gilchrist Co., Florida
Lived ~18 million years ago
Objects Reveal Evolution