Early horse — Protorohippus venticolum
Geologic period: Early Eocene — Wasatchian
Age: Early Eocene.
Taxonomic note: Modern systematic work recognizes Protorohippus venticolum as a distinct early equid lineage.
Feeding: Herbivorous browser.
Evidence: Skeleton, teeth and limbs directly document early equid anatomy.
Why it matters: Protorohippus records an early stage in horse evolution when equids were small, forest-associated and multi-toed.
Plain Language Identity: A small early Eocene horse from North America.
What You Are Looking At: A fossil skeleton of Protorohippus venticolum.
Ecosystem: Early Eocene terrestrial ecosystem.
Source Urls: https://naturalhistory.si.edu/visit/virtual-tour/current-exhibits/deep-time-virtual-tour-fossil-list; https://naturalhistory.si.edu/visit/virtual-tour/current-exhibits/deep-time-virtual-tour-fossil-list; https://www.cambridge.org/core/journals/journal-of-paleontology/article/stratigraphy-mammalian-paleontology-paleoecology-and-age-correlation-of-the-wasatch-formation-fossil-butte-national-monument-wyoming/DA1D75C44C42F59CEFDD2BD54CFC6D29
Enrichment Method: SAGE curated research pass; title + scientific name + source scene matched; chronology and taxonomy conflicts retained rather than silently corrected; evidence separated from inference
Scientific name: Protorohippus venticolum
Evidence / representation: Representative evidence-type visual; not the exact specimen.
Representative evidence-type visual; not the exact specimen.
After the Dinosaurs: Mammals, Ice Ages and the World We Inherited.
This object page stays inside SAGE Museum. The Smithsonian link below is provided only as the original scholarly collection record. It opens separately.