Evolution of Endemic Species, Ecological Interactions and Geographical Changes in an Insular Environment: A Case Study of Quaternary Mammals of Sicily (Italy, EU)

Antonella Marra

doi:10.3390/geosciences3010114

Abstract

The Quaternary mammals of Sicily are well known, and five faunal complexes have been distinguished on the basis of bioevents (extinctions and new arrivals) and evolution of endemic species. It is clear that the composition of mammal faunas is strictly related to the dispersal ability of each species and to the paleogeography of the area. Until now, researches have chiefly attributed paleogeographical changes as controlling these dispersals: the sea strait between the island and the Italian peninsula has had different widths and depths over time, operating different kinds of filters on the spreading of terrestrial mammals. Moreover, Sicily and its nearby mainland underwent changes in paleogeography. Some incongruence in bioevents has been attributed to the filter operated by the marine strait, which could have acted in differential ways on large and small mammals. However, the roles of ecological interactions among vertebrate species and their control on bioevents have been greatly underestimated. In this critical review, changes in mammals’ associations are reconsidered not only in terms of biochronology and dispersal ability of taxa through the marine strait, evolution of endemic features, in addition to the paleogeography of the island, but also considering the ecological role of each species and the interactions among the species with each faunal complex.

Highlights

In the last few decades, knowledge of the Quaternary mammals of the island of Sicily has increased, allowing new considerations of time periods and systems of faunal dispersals from the surrounding continental areas [1,2,3,4,5,6]
Experienced four different faunal complexes, characterized by the extinction of some species followed by the dispersal of newcomers from peninsular Italy [1,2,5]
The current faunal complexes are based on numerous sites and some of them were formerly excavated without screening for small mammals; it follows that large mammals have to be used to formalize faunal units, as do peninsular ones [12]

Summary

Introduction

In the last few decades, knowledge of the Quaternary mammals of the island of Sicily has increased, allowing new considerations of time periods and systems of faunal dispersals from the surrounding continental areas [1,2,3,4,5,6]. Its composition is very interesting and needs more investigation [1,2]. Experienced four different faunal complexes, characterized by the extinction of some species followed by the dispersal of newcomers from peninsular Italy [1,2,5]. Three faunal complexes include endemic species, evolved in insular conditions. Changes in faunal composition are related to dispersal events, followed by isolation phases, which induced processes of endemism in the pioneer species [2,5]

Objectives

Findings

Discussion

Conclusion