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The PREDICTS project—Projecting Responses of Ecological Diversity In Changing Terrestrial Systems (www.predicts.org.uk)—has collated from published studies a large, reasonably representative database of comparable samples of biodiversity from multiple sites that differ in the nature or intensity of human impacts relating to land use. We have used this evidence base to develop global and regional statistical models of how local biodiversity responds to these measures. We describe and make freely available this 2016 release of the database, containing more than 3.2 million records sampled at over 26,000 locations and representing over 47,000 species. We outline how the database can help in answering a range of questions in ecology and conservation biology. To our knowledge, this is the largest and most geographically and taxonomically representative database of spatial comparisons of biodiversity that has been collated to date; it will be useful to researchers and international efforts wishing to model and understand the global status of biodiversity.

Open vegetation (campinas and campinaranas) associated with white sand patches occurs in the form of islands in a forested matrix throughout the Amazon basin. Bird species restricted to these habitats have patchy distributions, although connectivity may have been influenced by past glacial cycles as a result of the substitution of forest by savanna. Because these landscape changes are a matter of debate in the history of Amazonia, we studied the diversification of Xenopipo atronitens, a white sand specialist, aiming to infer the effects of past climate changes. The split of Xenopipo atronitens from its sister species, Xenopipo uniformis, may be related to Tepuis erosion and retreat of escarpments during the Miocene, or to a dispersal event. Compared with birds from terra firme forest, X. atronitens has low genetic structure. Low levels of unidirectional gene flow were found from the Guyana Shield to adjacent areas. Demographic expansion starting approximately 25 kyr BP was detected for some populations and is probably related to the Last Glacial Maximum and subsequent climate improvement. Landscape genetic analyses indicate that the forested (terra firme) matrix acts as a barrier for the dispersal of X. atronitens. The results of the present study indicate that glacial cycles have deeply influenced Amazonian biogeographical history, demonstrating a complex interaction between forest and nonforest habitats during the Pleistocene. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110, 60–76.

Aim: To investigate the evolution of the avifauna associated to Amazonian fluvial islands, focusing on the Negro River archipelagos.Locations: Fluvial islands in the Amazon Basin.Methods: One generalist floodplain species (Hypocnemoides melanopogon) and three river island specialists (Myrmotherula assimilis, Myrmoborus lugubris and Thamnophilus nigrocinereus) were studied (Thamnophilidae). We sequenced two mitochondrial genes and genotyped eight microsatellite loci. Phylogenetic relationships among intraspecific lineages and divergence times were estimated using Bayesian Inference.Haplotype networks, AMOVA (analysis of molecular variance) and Mantel tests were used to verify the spatial organization of genetic diversity. Gene flow and population structure were evaluated using a dissimilarity index, Bayesian inference and allele frequencies. Historical demography was inferred through neutrality tests and Extended Bayesian skyline plots (EBSP).Results: River island specialists have evolved distinct lineages in different Amazonian tributaries, but exhibit very weak population structure within the Negro river basin. The generalist floodplain species had no population structure along the Amazon basin or within the Negro river basin. Signals of weak and recent (Pleistocene) population expansion were recovered for all species.Main conclusions: River islands specialists show stronger population structure within Amazonia than floodplain generalists. They show a common spatial and temporal pattern of divergence between populations from the Negro islands and western Amazonia (upper and middle Solimões), which may be related to Amazonian drainage evolution. Island specialists had low genetic diversity within the Negro basin, while the higher and unstructured diversity pattern found in the floodplain generalist species may be a consequence of higher dispersal caused by the seasonal flooding pulse. River islands populations have a recent and dynamic history of contact and isolation, with small historical fluctuations of population sizes, which is in sharp contrast with the patterns found in upland forest birds.

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