|Geoffroy's spider monkey (Ateles geoffroyi) |
What I found interesting is their attempt to place platyrrhine evolution in a biogeographical context. They suggest that the most recent common ancestor of extant species lived in what today is the Amazon rain forest, Guiana Shield and Northern Andes. Then, however, this was largely an area of lowlands and mountains. In support of their interpretation, known fossil sites are within this region. They further suggest that diversification of platyrrhines occurred with the establishment and development of the Amazon rain forest.
|Placenta of the white fronted capuchin (Cebus albifrons)|
From Carter and Mess (here)