The species composition of local flea assemblages at a small scale in two South American regions is predominantly driven by niche-based mechanisms

KRASBOV, B. R.; LOPEZ BERRIZBEITIA, M. F.; SANCHEZ, JULIANA P.; DÍAZ, M. M.; LARESCHI, M.; KHOKHLOVA, I. S.; GRABOVSKY, V. I.

PARASITOLOGY RESEARCH

SPRINGER

Lugar: Berlin; Año: 2022

0932-0113

We applied step-down factor analysis(SDFA) and multi-site generalized dissimilarity modelling (MS-GDM) to local fleacommunities harboured by small mammals (i.e., collected at small sampling sitesduring short time) in two South American regions (Patagonia and the NorthwesternArgentina) with the aim to understand whether these communities assembled vianiche-based or dispersal-based processes. The SDFA allows to answer whetherclusters of flea assemblages across different types of climates, vegetation, orsoil can be distinguished (suggesting niche-based assembly). MS-GDM allows toanswer whether a substantial proportion of the variation in flea speciesturnover is explained by specific climate-associated, vegetation-associated,and soil-associated variables (indicating niche-based assembly) or hostturnover (indicating dispersal-based assembly). Mapping of assemblages onclimate, vegetation, and soil maps according to their loadings on axis 1 oraxis 2 of the SDFA did not provide clear-cut results. Clusters of similarloadings could be recognized within some, but not other climate, vegetation,and soil types. However, MS-GDM demonstrated that the effect of environmentalvariables (especially, air temperature) exerted on flea compositional turnoverwas much stronger than that of host turnover indicating predominance ofniche-based processes in the assembly of local communities. Comparison of ourresults with those on mechanisms driving species assembly in regionalcommunities allows to conclude that local and regional communities result fromjoint acting of niche- and dispersal processes with the former more importantat a smaller spatial scale and the latter at a larger spatial scale.