New insights into the mechanisms into how ungulates got bigger in the Neogene

The observed increase of body size in ungulates during the 20 million years before the Pleistocene is driven by the process of species selection, according to researchers. Bigger ungulate species became more common because of a higher origination and lower extinction rate. The study is the first to compare the evolution of two mammalian clades during the Neogene on two continents. The researchers point out that this biogeographic perspective yields complex explanations for apparently shared patterns.
Paleontology News — ScienceDaily