Species-based functional description of the Canary Islands terrestrial subterranean fauna. On the left, density plots of functional contribution of individual species to the functional hypervolume of each island grouped according to their ontogenetic state. The species functional contribution of each species is maximum in Fuerteventura and minimal in Tenerife. The rest of the islands exhibit a similar average contribution per species (Hypothesis 2). The average and standard deviation of the contribution values per island are in parenthesis. All values are multiplied by 1000 to facilitate comparisons. On the right, plot of the absolute mantel test r values for each island against the island’s each. The curves have been obtained via quadratic approximation. Despite we only obtained significant values for the Mantel test in Tenerife, the mantel test r values indicate stronger species interactions in the mature islands.