Data from: Origins and diversification of the Caatinga dry forest endemic avifauna

Understanding the geographic origin of lineages is crucial for
comprehending their biogeographical and evolutionary histories, as well as
the historical connections among biomes. In northeastern Brazil, the
Caatinga dry forest represents the largest and most biologically diverse
patch of Seasonally Dry Tropical Forest in the Neotropics. Here, using the
endemic avian taxa of the Caatinga, we aim to i) infer their
biogeographical origins and timing of diversification, ii) investigate the
relationships with taxa from other Neotropical domains, and iii)
understand the processes driving the evolution and diversification of the
Caatinga endemic avifauna. We obtained previously published calibrated
phylogenies of 40 bird species endemic to the Caatinga to reconstruct
their ancestral geographic ranges through the R package BioGeoBEARS to
infer and highlight the origins, mode, and tempo of evolution of the
Caatinga avian endemics. Our results suggest that most avian
endemics (21 taxa) are related to lineages from open habitats, including
other dry forests or savannas; less than a quarter of the species (9 taxa)
likely colonized the Caatinga from adjacent humid forests; we also
highlight in situ origins (6 taxa), and cladogenetic events playing an
important role in the colonization of the domain. Although most of the
endemics seem to represent new arrivals from adjacent habitats, we also
detected relatively old lineages that likely occupied these dry landscapes
since the Miocene. We provide a much-needed framework for the
evolution and biogeographic diversification of the Caatinga Dry Forest.
The spatio-temporal patterns recovered here suggest an evolutionary
history influenced not only by strict vicariance events but also by
episodes of dispersal, which likely played a crucial role in the origin of
its avifauna. These events were likely influenced by major climatic and
geological events that formed ancient corridors, allowing connections
between the Caatinga and both dry and humid forests in South America.