Niche overlap and shared distributional patterns between two South American small carnivorans: Galictis cuja and Lyncodon patagonicus (Carnivora: Mustelidae)

Abstract

Limiting abiotic conditions might shapeboundaries of species distribution, while biotic factorsinfluence such distributions through interspecific relationships.When two morphologically and or/ecologicallysimilar species are geographically overlapped, adistribution displacement or a change in size or morphologyis expected to minimize competition. Environmentalniche modeling (ENM) might help us understandthe relationship between distribution of a species? pairand their relationship with environmental conditions,allowing us to test the possible existence of shared distributionpatterns and/or displacements across wide geographicranges. In this work, distribution patterns andclimatic and geographic overlap are analyzed betweentwo South American small carnivorans, Galictis cuja andLyncodon patagonicus, using geographic informationsystems and ENM. Environmental tolerance of the latterspecies seems to be enclosed within the range of the former,with high geographic overlap. No evidence of nichedisplacement was found between them. G. cuja seemsto be a more generalist species than L. patagonicus, andsize difference (e.g. body size, dentition size) might bethe mechanism that allows coexistence between thesehighly similar species, although future field studiesmight be needed to support this statement.