墨西哥“滞留围场”孕育了美洲生物大迁徙

A 10-million-year biogeographic holding pen primed the Great American Biotic Interchange Z. Jack Tseng1,2*, Leah X. Kahn1,3, Adolfo Pacheco-Castro2,4, Oscar Carranza-Castañeda5, José Jorge Aranda-Gomez5, Yang Wang6, Julio César Chávez-Ambriz5, Chance Hannold6, H. Gregory McDonald7, Xiaoming Wang2 The movement of taxa between North and South America across the Panamanian land bridge, known as the Great American Biotic Interchange (GABI), established modern-day mammal assemblages in the Americas, heralding the decisive end of what has been called the “splendid isolation” of the South American fauna. Lacking substantive low-latitude records, previous work on this pattern relied on South American and temperate North American fossils to conclude that pulsed interchanges began about 2.8 million years ago (mya). …