Ricerc@Sapienza

During the first decades of the last Century an enigmatic extinction was documented to have occurred on the small Mediterranean island of Santo Stefano and Sherlock Holmes was jokingly evoked to solve the mystery. Although islands are fascinating systems where to study microevolutionary processes, they may, on the other hand, host unstable communities that make their populations particularly vulnerable to anthropogenic effects and even to extinctions.

Community structure as summarized by presence–absence data is often evaluated via diversity measures by incorporating taxonomic, phylogenetic and functional information on the constituting species. Most commonly, various dissimilarity coefficients are used to express these aspects simultaneously such that the results are not comparable due to the lack of common conceptual basis behind index definitions.