Taphonomic and spatial analyses from the Early Pleistocene site of Venta Micena 4 (Orce, Guadix-Baza Basin, southern Spain).

Venta Micena is an area containing several palaeontological sites marking the beginning of the Calabrian stage (Early Pleistocene). The richness of the fossil accumulation including species of Asian, African and European origin, makes Venta Micena a key site for the the palaeoecological and palaeoenvironmental study of southern Europe during the Early Pleistocene. Thus, research has been focused on Venta Micena 3, which was originally interpreted as a single palaeosurface associated with a marshy context, in which most of the fauna was accumulated by Pachycrocuta brevirostris. Recent excavations have unearthed a new site, Venta Micena 4, located in the same stratigraphic unit (Unit C) and in close proximity to Venta Micena 3. Here we show the first analyses regarding the taphonomic and spatial nature of this new site, defining two stratigraphic boundaries corresponding to two different depositional events. Furthermore, the taphonomic analyses of fossil remains seem to indicate a different accumulative agent than Pachycrocuta, thus adding more complexity to the palaeobiological interpretation of the Venta Micena area. These results contribute to the discussion of traditional interpretations made from Venta Micena 3.

Excess protein enabled dog domestication during severe Ice Age winters.

Dogs (Canis familiaris) are the first animals to be domesticated by humans and the only ones domesticated by mobile hunter-gatherers. Wolves and humans were both persistent, pack hunters of large prey. They were species competing over resources in partially overlapping ecological niches and capable of killing each other. How could humans possibly have domesticated a competitive species? Here we present a new hypothesis based on food/resource partitioning between humans and incipient domesticated wolves/dogs. Humans are not fully adapted to a carnivorous diet; human consumption of meat is limited by the liver's capacity to metabolize protein. Contrary to humans, wolves can thrive on lean meat for months. We present here data showing that all the Pleistocene archeological sites with dog or incipient dog remains are from areas that were analogous to subarctic and arctic environments. Our calculations show that during harsh winters, when game is lean and devoid of fat, Late Pleistocene hunters-gatherers in Eurasia would have a surplus of animal derived protein that could have been shared with incipient dogs. Our partitioning theory explains how competition may have been ameliorated during the initial phase of dog domestication. Following this initial period, incipient dogs would have become docile, being utilized in a multitude of ways such as hunting companions, beasts of burden and guards as well as going through many similar evolutionary changes as humans.

Unique hip and stifle extensor muscle patterns in the Eurasian lynx, Lynx lynx (Carnivora: Felidae).

The Eurasian lynx (Lynx lynx) is a medium-sized felid, with a tendency to hunt for prey larger than itself. We studied the lynx hindlimb musculoskeletal anatomy in order to determine possible anatomical adaptations to hunting large prey. In our previous work, we had found characters of both large and small felids in the lynx forelimb. The crouched limbs, typical of all felids, increase the energy demands for the antigravity muscles during locomotion. As a powerful pounce is required for the smaller felid to bring down large prey, strong hindquarters may be needed. We hypothesized that the muscle attachments are more mechanically advantageous and muscles heavier in the lynx as compared to other felids to compensate for the energy requirements. In support of this, we found unique patterns in the hindlimb musculature of the lynx. Insertion of the m. gluteus medius was large with a short moment arm around the hip joint, providing mechanical disadvantage, but rapid movement. The musculus vastus medialis was relatively heavier than in other felids emphasizing the role of the m. quadriceps femoris as a powerful stifle extensor. The extensor muscles support the crouched hind limbs, which is crucial when tackling large prey, and they are also responsible for the swift powerful pounce brought by extending the hindlimbs. However, we cannot rule out the possibility the characters are shared with other Lynx spp. or they are adaptations to other aspects of the locomotor strategy in the Eurasian lynx.

A tall rostral hook in a medieval horse premolar tooth.

Development of dental abnormalities due to improper occlusal wear is common among modern domestic horses. This phenomenon often is attributed to jaw conformation. Rostral mandibular hooks may develop in horses with underjet or mandibular prognathism, a condition where the lower jaw protrudes forward, beyond the upper jaw. Less abrasive diet, free of phytoliths and matrix-like plant fibers, also may promote enamel and focal overgrowths of equine dentition. Here we report a rostral mandibular hook in a lower premolar tooth of a medieval horse, found in a spring deposit in Levänluhta, Osthrobothnia, Finland. To our knowledge, this is the first such report from a medieval horse.

Musculoskeletal anatomy of the Eurasian lynx, Lynx lynx (Carnivora: Felidae) forelimb: Adaptations to capture large prey?

Mammalian carnivores adhere to two different feeding strategies relative to their body masses. Large carnivores prey on animals that are the same size or larger than themselves, whereas small carnivores prey on smaller vertebrates and invertebrates. The Eurasian lynx (Lynx lynx) falls in between these two categories. Lynx descend from larger forms that were probably large prey specialists, but during the Pleistocene became predators of small prey. The modern Eurasian lynx may be an evolutionary reversal toward specializing in large prey again. We hypothesized that the musculoskeletal anatomy of lynx should show traits for catching large prey. To test our hypothesis, we dissected the forelimb muscles of six Eurasian lynx individuals and compared our findings to results published for other felids. We measured the bones and compared their dimensions to the published material. Our material displayed a well-developed pectoral girdle musculature with some uniquely extensive muscle attachments. The upper arm musculature resembled that of the pantherine felids and probably the extinct sabertooths, and also the muscles responsible for supination and pronation were similar to those in large cats. The muscles controlling the pollex were well-developed. However, skeletal indices were similar to those of small prey predators. Our findings show that lynx possess the topographic pattern of muscle origin and insertion like in large felids. J. Morphol. 277:753-765, 2016. © 2016 Wiley Periodicals, Inc.

[Encouraging experiences of interactive lectures]. / Luentojen vuorovaikutteisuus motivoi opiskelijoita ja luennoitsijoita.

BACKGROUND: Traditional lectures typically represent unidirectional transfer of information from teacher to students whilst interactive lectures involve student activity. MATERIAL AND METHODS: We analyzed the experiences of students and teachers of interactive lectures by observation and questionnaires during a course organized by Helsinki Biomedical Graduate School. RESULTS: Teachers and the majority of students found interactive lectures highly motivating although we observed that only a fraction of students participated in discussions. Students were of the opinion that interactivity improved their learning. CONCLUSIONS: Supplementing lectures with interactive elements encourages students to adopt active learning techniques.