Fossil Microvertebrates

This paper presents a preliminary quantitative analysis of some of the most important Maastrichtian microvertebrate assemblages from the Haţeg Basin, documenting the relative abundance of the identified taxa and discussing the palaeoecological significance of the differences derived from the current samples. The different abundance of the taxonomic groups, as well as the different abundance of taxa as grouped based on their diet and habitat point to significant between the studied assemblages, that appears to be closely related to the distance each local palaeoenvironment was placed from the river course (i.e. proximal vs. distal).

The Upper Cretaceous (Maastrichtian) continental deposits of the Haţeg Basin are well known for the diverse vertebrate assemblage they have yielded. Most of the taxa have been identified through intense micropaleontological processing of the material collected from across the basin. The floodplain deposits from several sites around the village of Vălioara are abundant in microvertebrate remains. This paper reports on the most important fossil remains recorded from a new site near Vălioara, first sampled in 2007, as well as the main sedimentary features presented by the deposits from this site. The fossil remains mainly consist of isolated teeth belonging to different crocodilian, theropod and multituberculate taxa, hosted by a gray-greenish pebbly mudstone, deposited within a poorly drained floodplain environment.

Known since the beginning of the 20 th century for their abundant and diverse paleofloristic content, the Maastrichtian deposits of the Rusca Montană Basin yielded no vertebrate fossils until recently, when sauropod, ornithopod, theropod, chelonian, crocodylian and multituberculate remains have been discovered in floodplain fines and river channel sandstones cropping out in the eastern part of the basin. This paper presents additional fossils from a potentially new site within the same area, belonging to taxa and metataxa previously unknown in the Rusca Montană Basin. The fossil assemblage includes anurans, albanerpetontids, lizards, ziphodont crocodylians, additional small theropods, eggshells, freshwater gastropods and angiosperm fructifications. The faunal and sedimentological data suggest that the fossil assemblage is largely autochthonous, and thus reflects the composition of a wetland, poorly drained distal floodplain paleo-ecosystem.

A B S T R A C T Very few excavated sequences in southern South America provide an approximation to the environmental evolution covering the segment Late Pleistocene-Holocene. Here we present the taphonomic analysis and pa-leoenvironmental reconstruction based on the small mammal remains retrieved from the archaeological and paleontological site Gruta del Indio (Mendoza Province, Argentina). Radiocarbon dates situate the small mammal deposits studied within the Late Pleistocene and Holocene. Thus, these assemblages provide a record for inferring environmental evolution in the middle basin of Atuel River during the last ∼31 ky BP. Taphonomic analysis revealed that most of small mammal remains were incorporated by a little destructive nocturnal owl. Recorded species include mainly cricetid and caviomorph rodents and a single marsupial. While Pleistocene assemblages have not exclusive species, the specific richness increases towards the Holocene probably linked with the climatic variability related to ENSO. In overall, the recorded small mammals suggest environmental stability during the Late Pleistocene-Holocene, mostly associated with Monte Desert conditions. Conversely, the pollen sequence studied from Gruta del Indio was interpreted as indicator of a deep environmental change during the Pleistocene-Holocene transition, when the Patagonian steppe was replaced by Monte Desert. Potential biases linked with these kinds of proxies are discussed.

The presence of microvertebrates in archaeological sites can be attributed to a variety of causes, including natural ones, such as the regurgitation of microvertebrates consumed by various predators. Determining the origin of these remains is therefore of great importance to our understanding of site formation processes. In addition, the detailed study of these remains can provide complementary data on such topics as the composition of biocenoses, palaeoenvironments and the seasonality of deposits. In this study, we analyzed modern sets of regurgitated pellets of the barn owl (Tyto alba) from the Alero Deodoro Roca site (ADR), Ongamira, Córdoba, Argentina. We compared the results with those from archaeological microvertebrates from excavations at ADR, dating to the Late Holocene (ca. 1900–3600 years BP). Most of the archaeological assemblages show the same composition as those of the modern pellets produced by Strigiformes. However, we observed variation in the representation of taxa, reflecting environmental changes over time. Using current temperature and humidity data to compare the assemblages, we observed that some results could be related to Holocenic climatic variations, already described by other studies. Furthermore, this research suggests that Strigiformes may occupy the rockshelters in Autumn-Winter, at which time the site (ADR) would not have been occupied so intensely by human populations.

A B S T R A C T Paleopathology in bones of very small mammals has rarely been studied. Different types of osseous lesions of mammals weighing under 0.2 kg, recovered from the Holocene strata of Cueva Tixi archaeological and pa-leontological site (Tandilia range, province of Buenos Aires, Argentina), are described and discussed in this report. Several types of trauma, entheseal changes, degenerative joint diseases, and probable osteomyelitis were identified. The lesions were chronic, indicating that the animals were able to survive a period of convalescence, although in many cases the decreased capacity for locomotion likely was significant. These pathological findings open research avenues for very small mammals that usually are not considered in archaeological disease studies.

CLIMATIC AND BIODIVERSITY CHARACTERIZATION IN THE LATE MIDDLE PLEISTOCENE FROM THE VERTEBRATE FAUNA OF LAZARET CAVE (NICE, FRANCE)
The Lazaret cave has yielded numerous Acheulean lithic industries and some anteneanderthal remains, but also an abundant vertebrate fauna (amphibians, reptiles, birds and mammals) revealing an important specific richness. The various faunal associations, as well as the evolutionary stage of some species, indicate that the archaeological deposits (Complex C) date from the last glacial period of the Middle Pleistocene (MIS 6). The interdisciplinary study of fauna from subcomplexes CIII and CII sup. suggests a variety of continental landscapes linked to a relatively cold climate that was moderated by the southern position of the site. The presence of cold climate species no longer present in the region implies colder and more humid
conditions than at present. Fluctuations are perceptible throughout the sequence, as indicated by variation in species abundance and species. A relative decrease in temperature and a gradual opening of the landscape occurred between subcomplexes CII sup. and CIII. The faunal spectrum of the Lazaret cave provides a relativey accurate reflection of the palaeobiodiversity of southern France at the end of the Middle Pleistocene (MIS 6).

En este trabajo se presenta el estudio de los micromamíferos del yacimiento de Morgotako Koba (Kortezubi, Bizkaia). Los roedores se
encuentran representados por siete taxones (Apodemus sylvaticus, Apodemus flavicollis, Arvicola amphibius, Microtus (Terricola) sp., Microtus (Alexandromys) oeconomus,  Microtus  (Microtus)  agrestis  y  Microtus  (Microtus)  arvalis),  y  los  insectívoros  por  dos  (Talpa  sp.  y Sorex  araneus-coronatus). El registro sedimentario esta subdividido en tres niveles, y la asociación conservada nos indica que el nivel Amp-Sa es el más cálido de los tres.
This paper provides the study of the small mammal assemblage from the site of Morgotako Koba (Kortezubi, Bizkaia). A total of nine species (Apodemus sylvaticus, Apodemus flavicollis, Arvicola amphibius, Microtus (Terricola) sp., Microtus (Alexandromys) oeconomus,
Microtus (Microtus) agrestis, Microtus (Microtus) arvalis, Talpa sp. and Sorex araneus-coronatus) have been identified. This assemblage indicates that the warmest environmental conditions occurred in the uppermost level of the sequence, identified as Amp-Sa.

Known since the beginning of the 20 th century for their abundant and diverse paleofloristic content, the Maastrichtian deposits of the Rusca Montană Basin yielded no vertebrate fossils until recently, when sauropod, ornithopod, theropod, chelonian, crocodylian and multituberculate remains have been discovered in floodplain fines and river channel sandstones cropping out in the eastern part of the basin. This paper presents additional fossils from a potentially new site within the same area, belonging to taxa and metataxa previously unknown in the Rusca Montană Basin. The fossil assemblage includes anurans, albanerpetontids, lizards, ziphodont crocodylians, additional small theropods, eggshells, freshwater gastropods and angiosperm fructifications. The faunal and sedimentological data suggest that the fossil assemblage is largely autochthonous, and thus reflects the composition of a wetland, poorly drained distal floodplain paleo-ecosystem.