Small forest equids
Early horse branches had low-crowned teeth and multiple toes, but later horse evolution forms a branching tree rather than a march toward one toe.
claim:taxon:perissodactyla:morphologyHorses from forest browsers to open-country runners
Horse evolution is a branching experiment, not a ladder marching toward one toe.
Each step names its evidence claims, with references below. Interactive Explorer states are available in the full application; the narrative remains an editorial synthesis.
Story sequence
Browsing persists
At Sandelzhausen, tridactyl and low-crowned Anchitherium aurelianense shows browse-dominated mixed feeding rather than a pure-browser stereotype.
claim:taxon:anchitheriumOpen habitats diversify the experiment
Hipparionins remained tridactyl while Old World lineages diversified from browse-dominated and mixed feeding to grazing across regions and time.
claim:taxon:hipparionini:ecologyReferences
- Evolutionary Transitions in the Fossil Record of Terrestrial Hoofed MammalsProthero, D.R. · 2009 · DOI 10.1007/s12052-009-0136-1
- Anchitherium aurelianense (Equidae, Mammalia): a brachydont “dirty browser” in the community of herbivorous large mammals from Sandelzhausen (Miocene, Germany)Kaiser, T.M. · 2009 · DOI 10.1007/s12542-009-0002-z
- Old world hipparion evolution, biogeography, climatology and ecologyBernor, R.L.; Kaya, F.; Kaakinen, A.; Saarinen, J.; Fortelius, M. · 2021 · DOI 10.1016/j.earscirev.2021.103784