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Early Pleistocene terrestrial climate conditions in the Mediterranean region, especially between 1.3 and 1.7 Ma, are poorly understood. Here, the amphibian and reptile fossil record from 24 fissures (Cava Pirro) of the Pirro Nord karstic complex (southern Italy) is used to infer quantitative paleoclimatic and paleoenvironmental reconstructions. These numerical data indicate that the mean annual temperature may have been somewhat lower (–1.6 to –3.6 °C compared to modern temperatures) than that of today, and the mean annual precipitation slightly higher (+90 to +240 mm) than modern values. Seasonality was more pronounced, with cooler summers (–0.4 to –2.0 °C) and much colder winters (–1.2 to –6.0 °C). Rainfall distribution patterns during the year show more precipitation during the winter (+14 to +43 mm), with quantities of summer rainfall (–1.7 to +6.6 mm) being similar to modern values. The associated landscape comprised an open dry environment with scattered patches of woodland, locally along water courses or around swamps. This ecological scenario fits with early Pleistocene cold conditions, where the first occurrence of some eastern emigrants suggests a scenario of trans-Adriatic dispersal, as may have also occurred for the earliest European hominins.

In contrast with the well documented strain on extant amphibian and reptile populations today, the Quaternary fossil record of these groups is very conservative showing few changes over long periods of time. In order to establish the non‐human‐induced effect of climate change on herpetofaunal diversity, we collected data from Pleistocene sites in the Sierra de Atapuerca complex (Burgos, Spain), which records the last few million years of changes. Diversity was measured in terms of richness and evenness indices and its relationship to the climatic parameters was analysed with OLS regression models. The highest diversity (richness and evenness; 1‐D) occurred in periods considered to be analogues of the current interglacial, whereas minimum diversity values were reached during periods when conditions were harsher (cooler or glacial stage). In all cases, the diversity values were always restored subsequently, pointing to great resilience. Temperature proves to be the most influential climatic factor. Accordingly, amphibians and reptiles have been able to overcome previous climatic changes successfully. In contrast, the effects of anthropization have generated an uncommon loss of diversity, the like of which has not been seen in the last few million years. The data presented here demonstrate that the current amphibian loss seems to be driven by anthropogenic influence, with climate a factor of a secondary importance.

Human movements in the regions surrounding the Mediterranean Sea have caused a great impact in the composition of terrestrial fauna due to the introductions of several allochthonous species, intentionally or not. Reptiles are one of the groups where this anthropic impact is most evident, owing to the extensive intra-Mediterranean dispersals of recent chronologies. Chalcides ocellatus is a widespread skink with a natural distribution that covers almost the entire Mediterranean Basin. Two hypotheses have been proposed to explain its origin: natural dispersions and human translocations. Previous molecular data suggest the occurrence of a recent dispersal phenomenon across the Mediterranean Sea. In this study we present the first record of this species in the Iberian Peninsula, in Serra del Molar (South-east Spain). We combined molecular analyses and archaeological records to study the origin of this population. The molecular results indicate that the population is phylogenetically closely related to specimens from north-eastern Egypt and southern Red Sea. We suggest that the species arrived at the Iberian Peninsula most likely through human-mediated dispersal by using the trade routes. Between the Iron to Middle Ages, even now, the region surrounding Serra del Molar has been the destination of human groups and commercial goods of Egyptian origins, in which Chalcides ocellatus could have arrived as stowaways. The regional geomorphological evolution would have restricted its expansion out of Serra del Molar. These findings provide new data about the impact of human movements on faunal introductions and present new information relating to mechanisms of long-distance translocations.

Artículo publicado en Open Access bajo los términos de Creative Commons attribution Non Comercial License 3.0. MONOGRÁFICO: Paleoecología, analizando la cuarta dimensión de la biodiversidad ecosistemas REVISTA CIENTÍFICA DE ECOLOGÍA Y MEDIO AMBIENTE

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