奇蹄目的兴衰

始新世的迅速登场

The earliest sampled perissodactyls occur during the PETM on northern landmasses, but those first fossils do not reveal an exact place or time of origin.

首次出现是化石观察值，并非精确起源时间。

温室世界中的食叶者

Eocene brontotheres radiate in North America and Asia while western European Palaeotherium medium provides a separate leaf-browsing sample; one ecology is not assigned to every lineage.

降温改变生态功能群

Marine records resolve stepwise ice growth, while the Hampshire mammal sequence separates turnover, a hiatus and later immigrant appearances; together they do not prove one simple cause.

特化者与幸存者

Living horses, tapirs and rhinoceroses are a narrow remnant of former perissodactyl diversity, and even Coelodonta species show that extinct rhinoceros ecology was not uniform.