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The tropics are the source of most biodiversity yet inadequate sampling obscures answers to fundamental questions about how this diversity evolves. We leveraged samples assembled over decades of fieldwork to study diversification of the largest tropical bird radiation, the suboscine passerines. Our phylogeny, estimated using data from 2389 genomic regions in 1940 individuals of 1283 species, reveals that peak suboscine species diversity in the Neotropics is not associated with high recent speciation rates but rather with the gradual accumulation of species over time. Paradoxically, the highest speciation rates are in lineages from regions with low species diversity, which are generally cold, dry, unstable environments. Our results reveal a model in which species are forming faster in environmental extremes but have accumulated in moderate environments to form tropical biodiversity hotspots. 

Abstract Background Bird plumage exhibits a diversity of colors that serve functional roles ranging from signaling to camouflage and thermoregulation. However, birds must maintain a balance between evolving colorful signals to attract mates, minimizing conspicuousness to predators, and optimizing adaptation to climate conditions. Examining plumage color macroevolution provides a framework for understanding this dynamic interplay over phylogenetic scales. Plumage evolution due to a single overarching process, such as selection, may generate the same macroevolutionary pattern of color variation across all body regions. In contrast, independent processes may partition plumage and produce region-specific patterns. To test these alternative scenarios, we collected color data from museum specimens of an ornate clade of birds, the Australasian lorikeets, using visible-light and UV-light photography, and comparative methods. We predicted that the diversification of homologous feather regions, i.e., patches, known to be involved in sexual signaling (e.g., face) would be less constrained than patches on the back and wings, where new color states may come at the cost of crypsis. Because environmental adaptation may drive evolution towards or away from color states, we tested whether climate more strongly covaried with plumage regions under greater or weaker macroevolutionary constraint. Results We found that alternative macroevolutionary models and varying rates best describe color evolution, a pattern consistent with our prediction that different plumage regions evolved in response to independent processes. Modeling plumage regions independently, in functional groups, and all together showed that patches with similar macroevolutionary models clustered together into distinct regions (e.g., head, wing, belly), which suggests that plumage does not evolve as a single trait in this group. Wing patches, which were conserved on a macroevolutionary scale, covaried with climate more strongly than plumage regions (e.g., head), which diversified in a burst. Conclusions Overall, our results support the hypothesis that the extraordinary color diversity in the lorikeets was generated by a mosaic of evolutionary processes acting on plumage region subsets. Partitioning of plumage regions in different parts of the body provides a mechanism that allows birds to evolve bright colors for signaling and remain hidden from predators or adapt to local climatic conditions. 

Describimos la composición de especies de aves del Parque Nacional Natural (PNN) Chingaza y su zona de amortiguación, a partir de la revisión de 10 estudios ornitológicos, trabajo de campo entre 2008–2017 y la expedición Colombia Bio en 2018. Reportarmos para el PNN Chingaza y su zona de amortiguación un total de 531 especies, agrupadas en 339 géneros y 57 familias. Seis especies presentes en el parque son endémicas de Colombia, 14 casi endémicas, 1 en peligro crítico, 6 en peligro, 4 vulnerables, 3 casi amenazadas y 37 migratorias. Esta lista incluye 149 especies adicionales a la información previamente conocida por datos publicados y colecciones ornitológicas. Adicionalmente, generamos códigos de barras genéticos, con base en secuencias del gen mitocondrial COI, para 74 especies y presentamos los primeros registros genéticos de Colombia en la plataforma para códigos de barra genéticos Barcode of Life Datasystems (BOLD) para Dysithamnus leucostictus, Chamaeza turdina, Rupicola peruvianus, Atlapetes semirufus, Euphonia mesochrysa y Chlorospingus flavopectus olsoni.  El presente listado es una herramienta para incentivar el estudio y conservación de las aves en este sector de la Cordillera Oriental colombiana.