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When waders gather in mixed‐species flocks to feed on benthic prey, differences in morphological traits, foraging strategies and prey selection may allow different species to optimize their energy intake while reducing competition. As the effect of the fine‐scale spatial distribution of resources on energy intake is unknown, we simulated the foraging performance of two types of waders with contrasting body plans and foraging strategies in a variety of virtual mudflats with different horizontal and vertical prey distribution patterns. Although larger, longer‐billed individuals had higher energy intake rates, smaller individuals with shorter bills maintained higher prey capture rates by relocating if prey was insufficiently available. Shorter‐billed individuals struggled more to meet their energetic demands because they selected smaller prey items and had a more limited capacity to metabolize energy from food. Being able to catch larger, high‐quality prey offered a competitive advantage for longer‐billed individuals, which could be a driving force for the evolutionary lengthening of bills in waders. Interestingly, their performance was more affected by the horizontal than by the vertical prey distribution. Quantifying prey distributions may help explain how some wader species can co‐occur in the field and why some wetland areas are unattractive as foraging areas. The work confirms that the foraging performance of larger, longer‐billed birds is not limited by bill size per se, but by the energetic trade‐offs associated with the ability to catch larger prey items more efficiently, increased handling times and higher absolute energy costs. These trade‐offs may become particularly important in landscapes where prey is scarce and spatially patchy. [ABSTRACT FROM AUTHOR]

Ecologists are intrigued by the manner in which colonists from a regional pool of species establish and structure local ecological communities. This has initiated several approaches to identifying the relative roles of regional and local processes. Recently, large-scale data sets and novel statistical tools have sparked renewed interest in objectively defined homogeneous species pools. At continental and global scales, these homogenous units are known as biogeographic species pools. Here we argue that the biogeographic species pool is not just a scaled-up version of the regional species pool featured in many foundational ecological theories. Instead, the processes linking local communities and regional species pools differ from those in the biogeographic species pool. To illustrate this, we distinguish between regional and biogeographic species pools by overlaying species distribution data and differentiat- ing between the intersection and union of these distributions. Although patterns in the regional and biogeographic species pools may appear self-similar across scales, the underlying mechanisms differ from those between local communities and the regional species pool. As a consequence, conventional approaches of quantifying the relative role of local and regional process are inappropriate for studying the biogeographic species pool, thus highlighting the need for new multi-scale theories in macroecology.

Developmental plasticity can help organisms to survive in temporally variable environments. However, it is not well understood how variation in life history plasticity helps species coexist in heterogeneous environments. Here, we investigate the extent to which life‐history plasticity explains species distributions in a diverse assemblage of odonates in a tropical freshwater rock pool system characterized by substantial variation in pond permanence. Some dragonflies and damselflies (Odonata) can accelerate their development to leave the water before their habitat dries. However, how they sense habitat drying is poorly understood.Here, we experimentally tested the extent to which elevated concentrations of salts in water or reductions in water level can be used as cues for developmental acceleration in a neotropical Odonata assemblage from granite rock pools.Libellulidae dragonflies were found along the permanence gradient and accelerated their growth in response to elevated dissolved salts (measured as conductivity). Anax amazili (Aeshnidae) was also found in all environments and did the same in response to lower water levels. In turn, larvae of the damselfly Telebasis simulata (Coenagrionidae) were restricted to deeper long‐lived pools and did not respond to the tested cues.Differentiation in life‐history strategies can contribute to niche differentiation in this diverse predator assemblage. Developmental plasticity triggered by different cues helps odonates avoid mortality and exploit short‐lived habitats. The global acceleration of freshwater salinisation due to human activities might disrupt the delicate links between low levels of dissolved salts and life‐history responses and represent a significant threat to these ecosystems and their biodiversity. [ABSTRACT FROM AUTHOR]

In variable environments the production of dormant life stages can help organisms to avoid periods that are unsuitable for growth and reproduction, and different species may rely on different cues to break dormancy. However, it is still unclear to what extent variation in germination strategies can help to explain variation in the distributions of related species and contribute to adaptive radiation. Using standardised laboratory germination trials, we demonstrated the existence of both inter‐ and intraspecific variation in germination strategies in two congeneric species of submerged macrophytes that occur in a dynamic wetland system characterised by strong variation in salinity and hydro‐regime.The ditch grass Ruppia maritima L. typically lives in temporary waterbodies, where it assures high seed set through a short life cycle, early flowering and self‐pollination. Its congeneric Ruppia spiralis L. ex Dumortier grows in (semi‐)permanent waterbodies where it can have a perennial life cycle. Populations are presumed to be maintained mainly through clonal growth, and seed production is lower than in R. maritima. We hypothesised that salt and temperature are two important germination cues in these ecosystems that can explain the observed differences in distribution patterns between these two species.We exposed seeds of both species in a full factorial designed experiment to four different salinities (0‰, 7‰, 14‰ and 21‰) and two different temperature regimes (17 and 24°C, simulating spring and summer temperatures, respectively). The experiment was repeated over three consecutive inundation cycles (30 days of inundation, followed by 30 days of drought). During the third cycle, all seeds were inundated with fresh water, as salinity might constraint germination in species that rely on fresh water for germination.We found that the R. maritima seeds had overall low germination success. The freshwater inundation caused rapid germination in seeds that previously were in a high‐salinity treatment. In R. spiralis, which inhabits more permanent habitats of variable salinity, we detected a more complex response, involving two germination peaks. These two contrasting germination strategies observed within R. spiralis could target spring or summertime growing periods respectively. We believe that the observed variation in germination strategies is an important element in ecological differentiation in the morphologically conserved genus Ruppia and may have contributed to past and ongoing speciation. [ABSTRACT FROM AUTHOR]