Habitat ranges of central Aegean islands' Oniscidea

Aim: To investigate responses of ecological specialization on area and environmental heterogeneity using a new metric.

Location: Aegean islands (Greece) as a case study.

Taxon: Terrestrial isopods as a case study.

Methods: The new metric, ‘ecorichness’, provides an estimate of an island’s species in the specialists-generalists spectrum. Species presences on each island are replaced with the numbers of habitats they exploit in the study system. Values are summed for each island and standardized by its species richness, giving the ‘ecorichness’ of each island. A data set with terrestrial isopods from 43 Aegean islands, and the respective description of habitats they exploit, was used as a case study. ‘Ecorichness’ was regressed on area, habitat diversity and the Choros model using linear and quadratic models, evaluated based on AICc. A reduced data set, without halophiles and coastal habitats, as well as an alternative description of habitat diversity, were also explored. The Sma...