Correction: A latitudinal phylogeographic diversity gradient in birds

Predicting genetic biodiversity in salamanders using geographic, climatic, and life history traits

The geographic distribution of genetic variation within a species reveals information about its evolutionary history, including responses to historical climate change and dispersal ability across various habitat types. We combine genetic data from salamander species with geographic, climatic, and life history data collected from open-source online repositories to develop a machine learning model designed to identify the traits that are most predictive of unrecognized genetic lineages. We find evidence of hidden diversity distributed throughout the clade Caudata that is largely the result of variation in climatic variables. We highlight some of the difficulties in using machine-learning models on open-source data that are often messy and potentially taxonomically and geographically biased.

Speciation-by-Extinction

Extinction is a dominant force shaping patterns of biodiversity through time; however its role as a catalyst of speciation through its interaction with intraspecific variation has been overlooked. Here, we synthesize ideas alluded to by Darwin and others into the model of "speciation-by-extinction" in which speciation results from the extinction of intermediate populations within a single geographically variable species. We explore the properties and distinguishing features of speciation-by-extinction with respect to other established speciation models. We demonstrate its plausibility by showing that the experimental extinction of populations within variable species can result in speciation. The prerequisites for speciation-by-extinction, geographically structured intraspecific variation and local extinction, are ubiquitous in nature. We propose that speciation-by-extinction may be a prevalent, but underappreciated, speciation mechanism.

Obligation to Enhance OBIS Data for Sea- and Shorebirds of the Americas

The distributions of many sea- and shorebird species span large geographic areas, making them ideal candidates as biomonitors of ecosystem perturbations and long-term environmental trends. The basic question examined in this study was: Does a major open-access data archive contain sufficient temporal- and spatial-scale data to support more detailed inquiry into multi-decadal-scale responses in geographic distributions of specific taxa? The global-scale open-access data platform, Ocean Biodiversity Information System (OBIS), was searched to compile data on bird distributions of the Americas, including the Caribbean Sea. More than 680,000 occurrence records of 210 species, collected between 1965 and 2018, were located and evaluated by marine ecoregion. The Puget Trough/Georgia Basin marine ecoregion, along the United States/Canadian border, and the Virginian marine ecoregion on the US east coast, dominated occurrences, each with more than 100,000 records, while the Gulf of Maine/Bay of Fundy had the most years of records (42). Most records from South America (~29,000) came from the Channels and Fjords of Southern Chile, collected across 16 different years. More than 90% of the recorded data were collected since 1983, and more than 95% of the records were from North American marine ecoregions. We urge additional observations to be shared via OBIS to allow comprehensive large-scale and detailed meta-analyses of spatial and temporal trends in marine and shore-bird communities and their biodiversity.