Chapter 2

Abstract

Three major carnivoran dispersal waves of filter-bridge type between Eurasia and North America are recognized in the late Neogene. The first is around 20 Ma, probably from 21 Ma to 19–18 Ma, during which intermittent dispersals might have occurred. The carnivorans migrating from Eurasia to North America included Cynelos, Ysengrinia, Amphicyon, Cephalogale, Phoberocyon, Ursavus, some small-sized mustelids, Potamotherium, an ancestral form of Edaphocyon, and Proailurus. The second wave occurred at about 7–8 Ma. The carnivorans migrating from Eurasia to North America included Indarctos, Agriotherium, Simocyon, Eomellivora, Plesiogulo, and Machairodus. The last wave took place in the early Pliocene ∼4 Ma. The Eurasian emigrants recorded in North America are Ursus, Parailurus, Lynx (?), Felis (?), Homotherium, and Chasmaporthetes. At about the same time Megantereon and Pannonictis migrated from North America to Eurasia.