The last interglacial-glacial cycle in the Meuse Valley (southern Belgium) inferred from the amphibian and reptile assemblages: implications for Neanderthals and anatomically modern humans

The Meuse and its tributary valleys contain numerous Late Pleistocene cave sites that have yielded one of the largest collections of Neanderthal and Mousterian lithic industries in Europe. Today, it is an important north-south migratory corridor for flora and fauna, generating rich biotopes. The Quaternary collections of the Royal Belgian Institute of Natural Sciences (Brussels, Belgium) are here used to complement our knowledge of the successive herpetofaunal assemblages in Belgium during the last interglacial-glacial cycle (marine isotope stages 5 to 1). Herpetofauna from 18 caves are described for the first time. In total, 17 taxa (10 amphibians and seven reptiles) are identified, three of which correspond to their first fossil record for Belgium (Alytes obstetricans, Pelobates fuscus, and Hyla arborea). The thermophilic snake Zamenis longissimus is documented for the first time in the Holocene (Atlantic/Subboreal period) of Belgium. After marine isotope stage (MIS) 5, the Belgian herpetofauna was still reasonably diverse during MIS 3, but it seems to be represented only by the common frog Rana temporaria and a viper during MIS 2. Paleoenvironmental and paleoclimatic reconstructions are proposed for a selection of the chronologically best-constrained sites, using the quantified ecology method. More specifically, the late Magdalenian of the Trou de Chaleux is reconstructed as particularly cold and dry. The seasonal contrast reaches its maximum during this period. The quantitative parameters calculated in this study provide a new paleoecological context for understanding the conditions with which the successive human species had to cope in Northwestern Europe during the last interglacial-glacial cycle.

Automated summary

This study describes the herpetofaunal assemblages in 18 caves in Belgium and provides a comprehensive understanding of the animal community during the last interglacial-glacial cycle using the Quaternary collections. The study also reconstructs the paleoenvironment and paleoclimate of selected sites using a quantified ecology method.