Early eocene vertebrates from baja california: evidence for intracontinental age correlations

Newly discovered fossils support a Wasatchian (early Eocene) age for the Punta Prieta vertebrate fauna of Baja California and reveal the utility of land mammal ages on a continental scale. Dispersal scenarios for late Paleocene and early Eocene vertebrates usually invoke heterochrony for similar, but geographically separated, faunas or taxa. Such heterochrony is not supported by independent geochronologies or adequate geographic samples.