Gaston's1 discussion of the patterns and mechanisms shaping distribution curves of species-range-sizes leaves out two important issues related to scale and hierarchical structuring of biota. Several provide evidence that species distributions are nested, that is, overlapping in a particular manner in which species with broad ranges often contain much smaller ranges of other species. In nested s...

• Changes in community composition resulting from climate change entail modifications of biotic interactions and reshape local species distributions. Such changes are currently occurring in nettle-feeding butterflies in Sweden where Araschnia levana has recently expanded its range northward and is now likely to interact with the resident species (Aglais urticae and Aglais io). Butterfly occurre...

Coral reefs are the most diverse ecosystem in the sea. Throughout the world they are being overfished, polluted and destroyed, placing biodiversity at risk. To date, much of the concern over biodiversity loss has centred on local losses and the possibility of global extinction has largely been discounted. However, recent research has shown that 24% of reef fish species have restricted ranges (<...

Geographic range size is often conceptualized as a fixed attribute of a species and treated as such for the purposes of quantification of extinction risk; species occupying smaller geographic ranges are assumed to have a higher risk of extinction, all else being equal. However many species are mobile, and their movements range from relatively predictable to-and-fro migrations to complex irregul...

Species range shifts associated with environmental change or biological invasions are increasingly important study areas. However, quantifying range expansion rates may be heavily influenced by methodology and/or sampling bias. We compared expansion rate estimates of Roesel's bush-cricket (Metrioptera roeselii, Hagenbach 1822), a nonnative species currently expanding its range in south-central ...

Contemporary climate change is causing large shifts in biotic distributions1, which has the potential to bring previously isolated, closely related species into contact2. This has led to concern that hybridization and competition could threaten species persistence3. Here, we use bioclimatic models to show that future range overlap by the end of the century is predicted for only 6.4% of isolated...

While it is generally recognized that noncontiguous (long-distance) dispersal of small numbers of individuals is important for range expansion over large geographic areas, it is often assumed that colonization on more local scales proceeds by population expansion and diffusion dispersal (larger numbers of individuals colonizing adjacent sites). There are few empirical studies of dispersal modes...

Reliable predictions for species range changes require a mechanistic understanding of range dynamics in relation to environmental variation. One obstacle is that most current models are static and confound occurrence with the probability of detecting a species if it occurs at a site. Here we draw attention to recently developed occupancy models, which can be used to examine colonization and loc...

Species distribution models (SDMs) assume equilibrium between species' distribution and the environment. However, this assumption can be violated under restricted dispersal and spatially autocorrelated environmental conditions. Here we used a model to simulate species' ranges expansion under two non-equilibrium scenarios, evaluating the performance of SDM coupled with spatial eigenvector mappin...