Pests or prey? Micromammal species within an ancient anthropic environment at the Norse settlement site of Tuquoy (Westray, Orkney).

Micromammals, like rodents and shrews, adapt rapidly to take advantage of new food sources, habitats and ecological niches, frequently thriving in anthropogenic environments. Their remains, often retrieved during archaeological investigations, can be a valuable source of information about the past environmental conditions as well as interspecies interactions and human activity. However, the research on such finds rarely covers multiple approaches, often relying on single species or data type (e.g. identification/information for proxy studies). Here we investigate micromammal remains from the Norse and medieval (AD tenth-fourteenth centuries) archaeological site at Tuquoy, Orkney, to elucidate the relationships between micromammals, humans and other species present using a variety of data. Four micromammal species were identified, and their species dynamics as well as relationships with humans could be inferred by tracking changes in spatial and temporal location of remains, from their taphonomic history and by age estimation for individual animals. A larger, predatory assemblage was also identified, with species composition differing from that in the rest of the archaeological assemblage, and possibly therefore representing small mammal species composition in the wild. The assemblage was probably deposited by a diurnal raptor, though identification to species is not certain due to post-depositional processes.

Rodents: food or pests in Neolithic Orkney.

Rodents have important effects on contemporary human societies, sometimes providing a source of food but more often as agricultural pests, or as vectors and reservoirs of disease. Skeletal remains of rodents are commonly found in archaeological assemblages from around the world, highlighting their potential importance to ancient human populations. However, there are few studies of the interactions between people and rodents at such sites and most of these are confined to locations where rodents have formed a part of the recent diet. Here we compare the accumulation pattern of rodent remains from four locations within and adjacent to the renowned Neolithic site of Skara Brae, Orkney, showing that those within the settlement itself were the result of deliberate human activity. The accumulation and nature of burnt bones, incorporated over an extended period within deposits of household waste, indicate that rodents were used as a nutritional resource and may have been the subject of early pest control. We, therefore, provide the first evidence for the exploitation or control of rodents by the Neolithic inhabitants of Europe.

Age-related changes in fear behavior and regional brain monoamines distribution in rats.

Differences in fear level assessment based on the time of motionless in the illuminated compartment, time spent in light compartment, number of head dipping from dark to the illuminated compartment and number of returns from dark to the illuminated compartment registered in light/dark transitions test and brain monoamines (NA, DA, 5-HT) and their metabolites (MHPG, DOPAC, 5-HIAA) in the hypothalamus, midbrain, amygdala, hippocampus and pons were examined in 3, 12 and 24 months old Wistar rats. The lowest level of fear was registered in 12 months old rats, a slightly higher level in 3 months old rats and the highest in 24 months old rats. Locomotion activity showed a decreasing tendency within age according to a linear dependence in 3, 12 and 24 months old rats. Neurochemical data showed the decreased activity of NA system and increased activity of DA system in most structures already occurred in 12 months old rats. It remained at the same level in aged rats. The correlation analysis between the behavioral markers of fear level and distribution of monoamines in young, mature and aged rats showed diversified data, only some of them being consistent with the "serotonergic hypothesis" of fear/anxiety. Therefore, we cannot conclude what neurochemical background of fear is.

Fear behavior and regional brain monoamines distribution after R(+)-8-OHDPAT and R(+)-UH-301 injections into the dorsal raphe nucleus in rats.

The effects of 8-OHDPAT and UH-301 injection into the dorsal raphe nucleus (DRN) on fear behavior of the light-dark transitions test and regional brain monoamines (NA, DA, 5-HT) and their metabolites (MHPG, DOPAC, 5-HIAA) in the hypothalamus (HPT), midbrain central gray matter (MID), amygdala (AMY), hippocampus (HIP) and pons (PO) were examined. An injection of 8-OHDPAT (300 ng) as well UH-301 (300 ng) into the DRN evoked an increase in the number of head dipping from dark to the illuminated compartment of chamber, an increase of time of motionless in the dark compartment and decrease of time of locomotion activity in the illuminated compartment. HPLC analysis showed reduction of 5-HIAA/5-HT ratio in the HPT, HIP and PO, increase of MHPG/NA ratio in the HIP and PO, and increase of DA content in the HPT, AMY and HIP after 8-OHDPAT injection. But injection of UH-301 reduced 5-HT in the MID and increased in the AMY, reduced 5-HIAA content in the HIP and increased in the MID and decreased MHPG/NA ratio in the PO. These results indicate that both 5-HT1A receptor agonists, acting on the 5HT1A autoreceptors caused the anxiolytic effects, reduced fear behavior on the rat connected with infringement of dynamic balance between the serotonergic and catecholaminergics systems.