Habitat filtering differentially modulates phylogenetic vs functional diversity relationships between dominant ground-dwelling arthropods in salt marshes

Abstract

20While mechanisms underlying biological diversities at different scales received huge attention over 21 the last decades, whether local abiotic factors driving functional and phylogenetic diversities can 22 differ among ecologically and phylogenetically closely related taxa remains under-investigated. In 23 this study, we compared correlations and drivers of functional (FD) and phylogenetic (PD) diversities 24 between two dominant taxa of ground-dwelling arthropods in salt marshes, spiders and carabids. 25Pitfall trapping in two sampling sites of N-W France resulted in the collection and identification of 26 more than 7000 individuals belonging to 67 species. Morphological and behavioral traits, as well as 27 molecular sequences of COI gene, were attributed to all species for calculating functional and 28 phylogenetic diversities respectively. Both taxa exhibited high correlation between FD and PD, which 29 was even higher in carabids probably due to their lower species richness. Analyses using Bayesian 30 framework and structural equation modeling revealed that FD and PD were positively influenced by 31 taxonomic diversity in spiders and carabids, but abiotic factors driving FD and PD differed between 32 taxa. Salinity especially drove the taxonomic diversity of carabids, but not that of spiders, suggesting 33 that spiders are more plastic and less selected by this factor. Phylogenetic diversity was conversely 34 influenced by salinity in spiders but not in carabids. This interesting result can be interpreted by 35 different evolutionary history and colonization process of salt marshes between the two model taxa. 36Our study finally highlights that, even in taxa of the same phylum and occupying the same niche in a 37 highly constrained habitat, functional and phylogenetic diversities can have different drivers, showing 38 different filtering mechanisms and evolutionary history at small spatial and temporal scales. 39 40

Comparative patterns in taxonomic and functional spider diversities between tropical vs. temperate forests

“…More specifically, we compared patterns of both taxonomic and functional diversities as they bring complementary information on ecological and evolutionary processes (Tucker et al, 2018). We first expected (a) correlated patterns between taxonomic and functional diversities (as previously documented in plants and vertebrates: see Tucker & Cadotte, 2013, but also in arthropods, e.g., Birkhofer et al, 2015 andRidel et al, 2020), (b) consistently (much) more diversity and evenness in tropical compared to temperate forests due a longer time of diversification processes leading to more species and traits co-existence, and (c) an order of magnitude between temperate and tropical forests in the same range than what previously reported for other arthropods, that is, diversity and evenness around 8 times higher in tropical compared to temperate forests.…”

Habitat filtering differentially modulates phylogenetic and functional diversity relationships between predatory arthropods

“…A total of 3359 adult spiders belonging to 55 species, of which 58.9% of individuals sampled are considered halophilic (appendix D, table 4), were collected by pitfall traps [78]. Spiders had an average size of 7.13 ± 3.79 mm.…”

Building a Robust, Densely-Sampled Spider Tree of Life for Ecosystem Research

“…Spiders are among the most diverse and abundant invertebrate predators in terrestrial habitats worldwide, and they play a key role in ecosystem functioning as top-down regulators of above-ground food webs [35]. However, while many studies have addressed community patterns of taxonomic and functional diversity both at global [36] and regional scales [29,37,38], to date, only two studies have included phylogenetic information in the analysis of spider communities [39,40].…”