Life‐history strategies in freshwater macroinvertebrates

Abstract

SUMMARY1. Explaining spatial and temporal differences in species assemblages is a central aim of ecology. It requires a sound understanding of the causal mechanisms underlying the relationship of species with their environment. A species trait is widely acknowledged to be the key that links pattern and process, although the enormous variety of traits hampers generalization about which combination of traits are adaptive in a particular environment. 2. In three steps, we used species traits to match species and environment, and chose lentic freshwater ecosystems to illustrate our approach. We first identified key environmental factors and selected the species traits that enable the organism to deal with them. Secondly, we investigated how investments in these traits are related (e.g. through trade-offs). Thirdly, we outlined 13 life-history strategies, based on biological species traits, their interrelations known from life-history theory and their functional implications. 3. Species traits and environmental conditions are connected through life-history strategies, with different strategies representing different solutions to particular ecological problems. In addition, strategies may present an integrated response to the environment as they are based on many different traits and their interrelationships. The presence and abundance of (species exhibiting) different life-history strategies in a location may therefore give direct information about how a particular environment is experienced by the species present. 4. Life-history strategies can be used to (i) explain differences in species assemblages either between locations or in different periods; (ii) compare waterbodies separated by large geographical distances, which may comprise different regional species pools or span species distribution areas and (iii) reduce often very complex, biodiverse assemblages into a few meaningful, easily interpretable relationships.

Causes and consequences of invertebrate drift in running waters: from individuals to populations and trophic fluxes

“…We offer a more nuanced perspective and suggest that drift may still be essential to spatial population dynamics, but the extent of its contribution depends on the broader life history adaptations of specific taxa (reviewed in Verberk et al 2008) and whether a taxa is recruitment-limited (at low densities below the capacity of the habitat). For taxa whose life history strategy is selected against strong nymphal dispersal, drift may be rare and have little consequence to population dynamics unless it is of sufficient magnitude to reduce a population below carrying capacity (e.g., catastrophic drift).…”

17 years of grassland management leads to parallel local and regional biodiversity shifts among a wide range of taxonomic groups

“…In addition, taxa also differ in their response to conservation management itself (van Klink et al 2015). The eight taxonomic groups we investigated differ in many respects, including dispersal ability, trophic position, body plan and development pathway, which all play a role in determining species' responses to their environment (Verberk et al 2008(Verberk et al , 2013. We have not formally tested which factors explain the differences in diversity shifts between taxonomic groups, because there are more potential factors than the number of taxonomic groups in our study, which leaves insufficient statistical power for formal testing.…”

Species traits reveal effects of land use, season and habitat on the potential subsidy of stream invertebrates to terrestrial food webs

“…Frainer and McKie 2015). Significantly, species traits are not independent entities, but because of ecological and evolutionary trade-offs involved in life-history strategies (Verberk et al 2008) are often linked into clusters or "syndromes", i.e., a group of tightly linked traits strongly associated with particular genera or families (Reich et al 2003;Poff et al 2006). Indeed, communities dominated by smaller, short-lived organisms with more flexible life cycles and generalist feeding behaviours often dominate human impacted streams (Statzner and Béche 2010), as species with these characteristics are favoured under the more extreme and less certain environmental conditions of degraded habitats.…”