Inner ear morphology in wild versus laboratory house mice.

The semicircular canals of the inner ear are involved in balance and velocity control. Being crucial to ensure efficient mobility, their morphology exhibits an evolutionary conservatism attributed to stabilizing selection. Release of selection in slow-moving animals has been argued to lead to morphological divergence and increased inter-individual variation.

Mapping small mammal optimal habitats using satellite-derived proxy variables and species distribution models.

Small mammal species play an important role influencing vegetation primary productivity and plant species composition, seed dispersal, soil structure, and as predator and/or prey species. Species which experience population dynamics cycles can, at high population phases, heavily impact agricultural sectors and promote rodent-borne disease transmission. To better understand the drivers behind small mammal distributions and abundances, and how these differ for individual species, it is necessary to characterise landscape variables important for the life cycles of the species in question.

Weather influences M. arvalis reproduction but not population dynamics in a 17-year time series.

Rodent outbreaks have plagued European agriculture for centuries, but continue to elude comprehensive explanation. Modelling and empirical work in some cyclic rodent systems suggests that changes in reproductive parameters are partly responsible for observed population dynamics. Using a 17-year time series of Microtus arvalis population abundance and demographic data, we explored the relationship between meteorological conditions (temperature and rainfall), female reproductive activity, and population growth rates in a non-cyclic population of this grassland vole species.

The changing pace of insular life: 5000 years of microevolution in the Orkney vole (Microtus arvalis orcadensis).

Island evolution may be expected to involve fast initial morphological divergence followed by stasis. We tested this model using the dental phenotype of modern and ancient common voles (Microtus arvalis), introduced onto the Orkney archipelago (Scotland) from continental Europe some 5000 years ago. First, we investigated phenotypic divergence of Orkney and continental European populations and assessed climatic influences.

Divergent evolutionary processes associated with colonization of offshore islands.

Oceanic islands have been a test ground for evolutionary theory, but here, we focus on the possibilities for evolutionary study created by offshore islands. These can be colonized through various means and by a wide range of species, including those with low dispersal capabilities. We use morphology, modern and ancient sequences of cytochrome b (cytb) and microsatellite genotypes to examine colonization history and evolutionary change associated with occupation of the Orkney archipelago by the common vole (Microtus arvalis), a species found in continental Europe but not in Britain.

Transmission ecosystems of Echinococcus multilocularis in China and Central Asia.

From continental to regional scales, the zoonosis alveolar echinococcosis (AE) (caused by Echinococcus multilocularis) forms discrete patches of endemicity within which transmission hotspots of much larger prevalence may occur. Since the late 80s, a number of hotspots have been identified in continental Asia, mostly in China, wherein the ecology of intermediate host communities has been described. This is the case in south Gansu, at the eastern border of the Tibetan plateau, in south Ningxia, in the western Tian Shan of Xinjiang, and in the Alay valley of south Kyrgyzstan.

Morphometrics as an insight into processes beyond tooth shape variation in a bank vole population.

Phenotype variation is a key feature in evolution, being produced by development and the target of the screening by selection. We focus here on a variable morphological feature: the third upper molar (UM3) of the bank vole, aiming at identifying the sources of this variation. Size and shape of the UM3 occlusal surface was quantified in successive samples of a bank vole population.

Modelling and spatial discrimination of small mammal assemblages: an example from western Sichuan (China).

We investigate the relationship between landscape heterogeneity and the spatial distribution of small mammals in two areas of Western Sichuan, China. Given a large diversity of species trapped within a large number of habitats, we first classified small mammal assemblages and then modelled the habitat of each in the space of quantitative environmental descriptors. Our original two step "classify then model" procedure is appropriate for the frequently encountered study scenario: trapping data collected in remote areas with sampling guided by expert field knowledge.

Developmental constraints revealed by co-variation within and among molar rows in two murine rodents.

Morphological integration corresponds to interdependency between characters that can arise from several causes. Proximal causes of integration include that different phenotypic features may share common genetic sets and/or interact during their development. Ultimate causes may be the prolonged effect of selection favoring integration of functionally interacting characters, achieved by the molding of these proximal causes.

A relict bank vole lineage highlights the biogeographic history of the Pyrenean region in Europe.

The Pyrenean region exhibits high levels of endemism suggesting a major contribution to the phylogeography of European species. But, to date, the role of the Pyrenees and surrounding areas as a glacial refugium for temperate species remains poorly explored. In the current study, we investigated the biogeographic role of the Pyrenean region through the analyses of genetic polymorphism and morphology of a typical forest-dwelling small mammal, the bank vole (Myodes glareolus).

New insight into the colonization processes of common voles: inferences from molecular and fossil evidence.

Elucidating the colonization processes associated with Quaternary climatic cycles is important in order to understand the distribution of biodiversity and the evolutionary potential of temperate plant and animal species. In Europe, general evolutionary scenarios have been defined from genetic evidence. Recently, these scenarios have been challenged with genetic as well as fossil data.

Transmission ecology of Echinococcus multilocularis: what are the ranges of parasite stability among various host communities in China?

A striking feature of the transmission ecology of Echinococcus multilocularis in China is the diversity of hosts that contribute to the parasite cycle. Considering the population dynamics of key reservoir intermediate hosts and the ratio of their preferred habitat in a landscape (ROMPA) is essential to understanding transmission, but the numerous communities in which the parasite cycles and the extent of those communities is currently far from being fully documented. On the Tibetan plateau grassland management influences intermediate host species populations and the sheer size of the area could be a major contributing factor to sustaining transmission in the region.

Is the prevalence of Taenia taeniaeformis in Microtus arvalis dependent on population density?

Populations of common voles Microtus arvalis were studied as hosts of the tapeworm Taenia taeniaeformis during a 14-yr survey. They were monitored in spring, summer, and autumn in a pastoral ecosystem in eastern France. A total of 7,574 voles were sampled during 2 multiannual population fluctuations.