Global and regional climate change impacted Paleogene mammal faunas in Central Asia
2026-09-08
Global climate change has been linked to faunal turnover throughout geological history, but the effects of regional environmental change remain comparatively less understood. Central Asian environments changed repeatedly throughout the Paleogene (ca. 66 to 23 Ma) due to topographic reshaping and global climate change. Additionally, recently published geological records indicate that intense, regional aridification occurred during the mid-Eocene. We test the signatures of regional versus global climate change events in the fossil record, reconstructing Paleogene sampling-corrected taxonomic richness, faunal turnover, and body size change for all Central Asian mammals. We find three macroevolutionary transitions in mammal assemblages. One associated with regional Asian mid-Eocene aridification and two with global events — the Paleocene-Eocene Thermal Maximum (short-lived extreme warming 56 Ma) and the Eocene-Oligocene Transition (prolonged cooling 34 Ma). Our results indicate that both global and regional climate were associated with mammal evolution in the Paleogene of Asia. We also find that a previously described Eocene/Oligocene transition from Perissodactyla-dominated to Glires-dominated faunas — thought to be associated with cooling at the Eocene-Oligocene Transition – may be a sampling bias artifact.