MotivationThe BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community‐led open‐source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene.Main types of variables includedThe database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record.Spatial location and grainBioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km2 (158 cm2) to 100 km2 (1,000,000,000,000 cm2).Time period and grainBioTIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year.Major taxa and level of measurementBioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates.Software format.csv and .SQL.

The importance of predation risk as a key driver of evolutionary change is exemplified by the Northern Range in Trinidad, where research on guppies living in multiple parallel streams has provided invaluable insights into the process of evolution by natural selection. Although Trinidadian guppies are now a textbook example of evolution in action, studies have generally categorized predation as a dichotomous variable, representing high or low risk. Yet, ecologists appreciate that community structure and the attendant predation risk vary substantially over space and time. Here, we use data from a longitudinal study of fish assemblages at 16 different sites in the Northern Range to quantify temporal and spatial variation in predation risk. Specifically we ask: 1) Is there evidence for a gradient in predation risk? 2) Does the ranking of sites (by risk) change with the definition of the predator community (in terms of species composition and abundance currency), and 3) Are site rankings consistent over time? We find compelling evidence that sites lie along a continuum of risk. However, site rankings along this gradient depend on how predation is quantified in terms of the species considered to be predators and the abundance currency is used. Nonetheless, for a given categorization and currency, rankings are relatively consistent over time. Our study suggests that consideration of predation gradients will lead to a more nuanced understanding of the role of predation risk in behavioral and evolutionary ecology. It also emphasizes the need to justify and report the definition of predation risk being used.

This is an open access article under the terms of the Creat ive Commo ns Attri bution-NonCo mmercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Human activities are altering the structure of ecosystems, compromising the benefits they provide to nature and people. Effective conservation actions and management under ongoing global change rely on a better understanding of socio-ecological patterns and processes across broad spatiotemporal scales. Both macroecology and conservation science contribute to this improved understanding and, while they have different scopes, these disciplines have become increasingly interconnected over time. Here we describe examples of how macroecology has Highlights• Understanding broad-scale biological patterns and processes is crucial for effective conservation actions and management under ongoing global change.• While Macroecology and Conservation science have different scopes, they have influenced -and benefitted from -each other over time.• Macroecology has contributed to conservation by developing ecological theory and methodological approaches, making data more accessible, and addressing knowledge gaps.• Macroecology has capitalized on data-gathering that was originally intended to support conservation initiatives, and gained an improved understanding of how natural patterns have been altered by recent human impact.• Untapped opportunities remain that could foster additional interconnections and aid further development of both disciplines. We present possible solutions to improve connections and new avenues for macroecological research that can benefit conservation science.

Ecological assemblages are inherently uneven, with numerically dominant species contributing disproportionately to ecosystem services. Marked biodiversity change due to growing pressures on the world's ecosystems is now well documented. However, the hypothesis that dominant species are becoming relatively more abundant has not been tested. We examined the prediction that the dominance structure of contemporary communities is shifting, using a meta-analysis of 110 assemblage timeseries. Changes in relative and absolute dominance were evaluated with mixed and cyclic-shift permutation models. Our analysis uncovered no evidence of a systematic change in either form of dominance, but established that relative dominance is preserved even when assemblage size (total ) changes. This suggests that dominance structure is regulated alongside richness and assemblage size, and highlights the importance of investigating multiple components of assemblage diversity when evaluating ecosystem responses to environmental drivers.

We compared preferences shown by zebrafish Danio rerio and three‐spined stickleback Gasterosteus aculeatus for shelter provided by above‐tank shade and artificial plants. Zebrafish showed no preference for either shelter, whereas sticklebacks showed a preference for both shelter types over open areas and for shade over plants. Our results suggest shade may be used as enrichment for captive fish and re‐emphasise the importance of species‐specific welfare considerations.

As pressures on biodiversity increase, a better understanding of how assemblages are responding is needed. Because rare species, defined here as those that have locally low abundances, make up a high proportion of assemblage species lists, understanding how the number of rare species within assemblages is changing will help elucidate patterns of recent biodiversity change. Here, we show that the number of rare species within assemblages is increasing, on average, across systems. This increase could arise in two ways: species already present in the assemblage decreasing in abundance but with no increase in extinctions, or additional species entering the assemblage in low numbers associated with an increase in immigration. The positive relationship between change in rarity and change in species richness provides evidence for the second explanation, i.e. higher net immigration than extinction among the rare species. These measurable changes in the structure of assemblages in the recent past underline the need to use multiple biodiversity metrics to understand biodiversity change.

Extinction rates are predicted to accelerate during the Anthropocene. Quantifying and mitigating these extinctions demands robust data on distributions of species and the diversity of taxa in regional biotas. However, many assemblages, particularly those in the tropics, are poorly characterized. Targeted surveys and historical museum collections are increasingly being used to meet the urgent need for accurate information, but the extent to which these contrasting data sources support meaningful inferences about biodiversity change in regional assemblages remains unclear.Here, we seek to elucidate uncertainty surrounding regional biodiversity estimates by evaluating the performance of these alternative methods in estimating the species richness and assemblage composition of the freshwater fish of Trinidad & Tobago.We compared estimates of regional species richness derived from two freshwater fish datasets: a targeted two year survey of Trinidad & Tobago rivers and historical museum collection records submitted to The University of the West Indies Zoology Museum. Richness was estimated using rarefaction and extrapolation, and assemblage composition was benchmarked against a recent literature review. Both datasets provided similar estimates of regional freshwater fish species richness (50 and 46 species, respectively), with a large overlap (85%) in species identities. Regional species richness estimates based on survey and museum data are thus comparable, and consistent in the species they include. Our results suggest that museum collection data are a viable option for setting reliable baselines in many tropical systems, thereby widening options for meaningful monitoring and evaluation of temporal trends.Abstract in Spanish is available with online material.