Speciation dynamics of the fruit-eating bats (genus Artibeus): With evidence of ecological divergence in Central American populations

An increasing number of studies have identified complex diversification patterns of Neotropical faunal groups. One example of such complexity is found in bats of the widely distributed and locally abundant Neotropical genus Artibeus, wherein both allopatric and hybrid speciation events have been hypothesized. However, conflicting hypotheses regarding the timescale of diversification for Artibeus exist, and therefore, temporal inferences of the speciation events within the genus remain in doubt. We examine hypotheses regarding the chronology of diversification events within Artibeus. Our results indicate the most parsimonious time of origin for the genus was during the late Miocene to early Pliocene, with multiple speciation events during the early Pleistocene. Considering this evolutionary timescale, we revisit a century-old systematic debate regarding the status of Central American populations known as Artibeus lituratus intermedius. We present nuclear genetic data that indicate intermedius is distinct from lituratus and hypothesize that this distinction was ecologically driven, likely involved sympatry and reinforcement, and occurred during the late Pleistocene or early Holocene. Collectively, the data from Artibeus indicate that multiple speciation processes underlie extant levels of diversity within the genus. Our analyses provide further evidence for complex origins of the Neotropical fauna and contribute to a greater understanding of the natural processes underlying the origin of species.