An odd-toed world
Eocene brontotheres span small early species to rhinoceros-sized forms across North America and Asia, illustrating an extinct herbivore radiation rather than a modern analogue.
claim:taxon:brontotheriidae:ecologyChanging of the herbivore guild
Compare ecological succession with ancestry—and see why resemblance does not imply descent.
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
The rules change
Near the Eocene–Oligocene boundary, marine ice-growth steps and the regional Hampshire mammal sequence can be aligned, but turnover, hiatus and immigration remain distinct observations.
claim:event:eocene-oligocene-transitionOverlap before replacement
Miocene Anchitherium, hipparionins and Teleoceras occupied different dietary niches whose evidence varies by lineage and locality; guild change was prolonged rather than instantaneous.
claim:taxon:anchitherium · claim:taxon:hipparionini:ecology · claim:taxon:teleocerasReferences
- Species Taxonomy, Phylogeny, and Biogeography of the Brontotheriidae (Mammalia: Perissodactyla)Mihlbachler, M.C. · 2008 · DOI 10.1206/0003-0090(2008)501[1:STPABO]2.0.CO;2
- Rapid stepwise onset of Antarctic glaciation and deeper calcite compensation in the Pacific OceanCoxall, H.K.; Wilson, P.A.; Pälike, H.; Lear, C.H.; Backman, J. · 2005 · DOI 10.1038/nature03135
- Eocene–Oligocene mammalian faunal turnover in the Hampshire Basin, UK: calibration to the global time scale and the major cooling eventHooker, J.J.; Collinson, M.E.; Sille, N.P. · 2004 · DOI 10.1144/0016-764903-091
- 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
- Tale of two rhinos: isotopic ecology, paleodiet, and niche differentiation of Aphelops and Teleoceras from the Florida NeogeneMacFadden, B.J. · 1998 · DOI 10.1666/0094-8373(1998)024[0274:TOTRIE]2.3.CO;2
- Enamel carbon, oxygen, and strontium isotopes reveal limited mobility in Teleoceras major at Ashfall Fossil Beds, Nebraska, USAWard, C.T.; Crowley, B.E.; Secord, R. · 2025 · DOI 10.1038/s41598-025-94263-z