Naroa Garcia-Ibaibarriaga

Combining Small-Vertebrate, Marine and Stable-Isotope Data to Reconstruct Past Environments

Three very different records are combined here to reconstruct the evolution of environments in the Cantabrian Region during the Upper Pleistocene, covering ~35.000 years. Two of these records come from Antoliñako Koba (Bizkaia, Spain), an exceptional prehistoric deposit comprising 9 chrono-cultural units (Aurignacian to Epipaleolithic). The palaeoecological signal of small-vertebrate communities and red deer stable-isotope data (δ13C and δ15N) from this mainland site are contrasted to marine microfaunal evidence (planktonic and benthic foraminifers, ostracods and δ18O data) gathered at the southern Bay of Biscay. Many radiocarbon dates for the Antoliña’s sequence, made it possible to compare the different proxies among them and with other well-known North-Atlantic records. Cooling and warming events regionally recorded, mostly coincide with the climatic evolution of the Upper Pleistocene in the north hemisphere.

Paleoenvironmental and Paleoclimatic Approach to the Upper Pleistocene Site of Artazu Vii (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.