Paleoenvironmental and Paleoclimatic approach to the Late Pleistocene site of Artazu (Arrasate, Northern Iberian Peninsula) using small vertebrates

Abstract

The Artazu VII site (Arrasate, northern Iberian Peninsula) is a fossiliferous deposit that was discovered unsystematically at the Kobate Quarry in 2012. During the following year, all the vertebrate remains attributed to the upper Pleistocene (~ 93 ka) were recovered in an emergency excavation project. Here, we describe, for the first time, the small vertebrate assemblage (amphibians, reptiles, and small mammals) recovered from the site, as well as the environmental and climatic results estimated from the paleoecological affinities of the studied taxa. More than 50,000 microvertebrate elements were recovered, comprising 24 taxa of which seven belong to the Order Rodentia; five, to the Order Eulipotyphla; one, to the Order Chiroptera; seven, to the Order Anura; and four, to the Order Squamata. Considering the environmental attributions and the relative abundance of each taxon, the paleoenvironmental and paleoclimatic conditions were reconstructed and the sequence was divided into three phases. Although woodland mass is present in the whole sequence, expansion and regression changes can be observed. Thus, the stratigraphic sequence begins with a landscape with open spaces. Higher up the stratigraphic column, woodland expands and reaches its maximum development in the second phase. Finally, the woodland environment declines and reaches similar values to those of the initial situation. These forestry biotopes were related to temperate and humid conditions comparable to those of the modern landscape. It was also concluded that a watercourse existed near the site.