Résumé
The origins and evolution of the outstanding Neotropical biodiversity are
a matter of intense debate. A comprehensive understanding is hindered by
the lack of deep-time comparative data across wide phylogenetic and
ecological contexts. Here, we quantify the prevailing diversification
trajectories and drivers of Neotropical diversification in a sample of 150
phylogenies (12,512 species) of seed plants and tetrapods and assess their
variation across Neotropical regions and taxa. Analyses indicate that
Neotropical diversity has mostly expanded through time (70% of the
clades), while scenarios of saturated and declining diversity account for
21% and 9% of Neotropical diversity, respectively. Five biogeographic
areas are identified as distinctive units of long-term Neotropical
evolution, including Pan-Amazonia, the Dry Diagonal, and
Bahama-Antilles. Diversification dynamics do not differ across these
areas, suggesting no geographic structure in long-term Neotropical
diversification. In contrast, diversification dynamics differ across taxa:
plant diversity mostly expanded through time (88%), while a substantial
fraction (43%) of tetrapod diversity accumulated at a slower pace or
declined toward the present. These opposite evolutionary patterns may
reflect different capacities for plants and tetrapods to cope with past
climate changes