Early reliable evidence of the Etruscan shrew (Suncus etruscus) in southwestern Europe during ancient times. Reconstructing its dispersal process along the Mediterranean Basin

Abstract

This paper reports a new and well dated record of the Etruscan shrew (Suncus etruscus), which is the smallest extant terrestrial mammal, and provides a comprehensive review of the fossil record of this species. Three remains were found in the small vertebrate assemblage of the Estrecho Cave (Cuenca, Spain), which dates from 2310–2290 and 2272–2149 years cal BP. The morphometric analysis performed provided unequivocal traits of this species. We analyse this new record of the Etruscan shrew together with a review of its fossil records along the Mediterranean Basin. Because of the scarcity of reliable records of this species, its origin and palaeobiogeographical history remain still unclear. According to available data, the Etruscan shrew populations that colonised Europe were most probably originated in Asia, where it was present at least since the Middle Pleistocene. Its dispersal process across the Mediterranean Basin shows a pattern in which it progressively extended its distribution towards the west from mid-4th millennium BP onwards. This process most certainly involved the accidental translocation of the species by humans across the Mediterranean through navigation routes, resulting in its introduction into most of the large Mediterranean islands, besides the mainland of Europe and North Africa.