The ecology of a continental evolutionary radiation: Is the radiation of sigmodontine rodents adaptive?

• DOI: 10.1111/evo.13155
• Publication Date: 2016-12-27T05:24:45Z
• Authors: Renan Maestri; Leandro Rabello M...; Rodrigo Fornel; Nathan S. Upham; Bruce D. Patterson; Thales Renato Och...
• Keywords: Adaptive Radiation; Ecomorphology; Macroevolution; Lineage (genetic)

Evolutionary radiations on continents are less well-understood and appreciated than those occurring islands. The extent of ecological influence species divergence can be evaluated to determine whether a radiation was ultimately the outcome divergent natural selection or else arose mainly by nonecological divergence. Here, we used phylogenetic comparative methods test distinct hypotheses corresponding adaptive nonadaptive evolutionary scenarios for morphological evolution sigmodontine rodents. Results showed that variables (diet life-mode) explain little shape size variation skulls mandibles. A Brownian model with varying rates insectivory versus all other diets most likely model. insectivorous sigmodontines have faster rate mice feeding diets, possibly due stronger features aid insectivory. We also demonstrate rapid early-lineage diversification is not accompanied high among subclades, contrasting island results. geographic permits spatial segregation greater islands, allowing allopatric distributions escape from interspecific competition. suggest continental rodents produce pattern coupled low degree phenotypic specialization.