South American Land mammal faunas during the Cretaceous Tertiary transition: evolutionary biogeography

ORTIZ JAUREGUIZAR, EDGARDO; PASCUAL, ROSENDO

La Plata

Simposio; Simposios sobre el Cretácico de América Latina, parte A: Eventos y registro sedimentario; 1989

Facultad de Ciencias Naturales y Museo (UNLP)

In this paper we analyze the so far recorded successive changes of the lamd-mammal communities during the Late Cretaceous-Tertiary transition with two main purposes: (1) to assess if they were the effects of widespread (global) geographical-environmental perturbations (biotic and abiotic) influencing most habitats; and (2) to evaluate how the regional (continental) and and biological shares drove the apparently different patterns of changing communities. To evaluate more justly the changes in mammal communities along with the more restricted Cretaceous-Tertiary transition, we also analyze the known record of mammals immediately early and later to this boundary. This fcontribution intends to furnish, an up-to-date general background to the everyday innovated knowledge of' the root of the South American "Age of Mammals".