Tracking wetland community evolution using Diptera taxonomic, functional and phylogenetic structure

Abstract

Different processes drive spatial variation in community composition. Standard measures of composition are useful in species‐based conservation and ecology, but they may be less informative in the context of evolutionary history and functional diversity. Functional and phylogenetic approaches are increasingly used to test mechanisms driving biodiversity patterns. We studied 28 families of flies (Diptera) with a range of functional characteristics in three wetland classes (bogs, swamps, marshes) in Quebec, Canada. We examined taxonomic, phylogenetic and functional structure of communities and assessed whether rarity is deterministic or stochastic. Beta‐ and phylobeta‐diversity were also examined for relatedness to local environmental conditions, patch area, and/or surrounding landscape. Phylogenetic community structure analyses had high value and complementarity to standard measures. Environmental filtering acted on bog communities during assembly, as they emerged from a slow peat accumulation process and the plant composition is characteristic as few species can survive in these acidic and low nutrient conditions. Subsequently, community assembly happened randomly. Neutral processes of community assembly are more important in marshes and swamps, as dispersal limitation explained species abundance dynamics of small and common Diptera species. The assembly of marsh communities is a balance between neutral processes and environmental filtering, while assembly in swamps can be seen as neutral. Clustering increased with environmental extremes, indicating environmental filtering. Rare species tended to be less closely related to common species. They have unique habitat requirements, and the high diversity is maintained by temporal turnover of species with similar traits filtered by the environment.

Saproxylic Diptera assemblages in a temperate deciduous forest: implications for community assembly

“…Using a morphospecies approach we were able to obtain finer scale identification, but to fully understand community assembly patterns, more identification tools (including molecular techniques) of the broader community (including all invertebrates and fungi) and in-depth life-history information are needed. Our results suggest that Diptera community assembly may be driven by both stochastic and deterministic processes which is in support of recent studies in community assembly ( Gravel et al, 2006 ; Thompson & Townsend, 2006 ; Ellwood, Manica & Foster, 2009 ; Barber & Marquis, 2011 ; Ferrenberg, Martinez & Faist, 2016 ; Grégoire Taillefer & Wheeler, 2017 ). We have also demonstrated that to retain the highest saproxylic Diptera diversity in a forest, a variety of decaying wood types at different stages of decomposition is necessary.…”

Ecology of Terrestrial Arthropods in Freshwater Wetlands

“…Since the review of Spitzer & Danks (120), more recent literature has expanded on some of the themes that they developed, with mixed success. The unique environmental conditions and plant communities in peatlands were found to have a stronger control on dipteran assemblages than they did in marshes and swamps (124). Hummock-hollow microtopography was found to control communities of microarthropod decomposers (8).…”

DNA metabarcoding reveals metacommunity dynamics in a threatened boreal wetland wilderness

“…This total may still underestimate the total diversity present, and we demonstrate the importance sampling errors can have for modeling this community. Communities exhibited near-random patterns of spatial and temporal turnover, a property rarely observed in freshwater systems (33). As a result, impacts on the wetland macroinvertebrate community are difficult to establish at local scales because occurrence is weakly related to environmental factors and site composition can fluctuate rapidly over time (SI Appendix, Fig.…”