A geometric morphometric analysis was carried out on the crania of 13 species of elephant-shrews (Macroscelidea), a group of African mammals whose phylogeny is still debated. The material examined consisted of 313 crania and included all the genera of Macroscelididae, the unique family recognized by taxonomists. The results obtained from the analysis of the cranium shape and size, either from dorsal or lateral view, were very similar. The Wrst one appeared more reliable because of the higher number of intersection points Wxed between the cranial sutures. All the cranial features that distinguished the genus Rhynchocyon were a consequence of the extreme enlargement of frontal bones. Instead, within the subfamily Macroscelidinae, the diVerences between genera were based on modiWcation involving other bones, mainly mastoids and nasals, as shown by the deformation grids. A cluster analysis conWrmed the traditional subdivision in two subfamilies (Rhynchocyoninae and Macroscelidinae) but suggested a diVerent relationship among the recognized genera belonging to Macroscelidinae. Our results are congruent with data obtained from previous biochemical research and support the traditional subdivision in two subfamilies, the monophily of the genus Elephantulus and its closeness with Petrodromus, relating to their similar cranium shapes. The latter presumably is a case of gigantism as adaptation to forest habitats. Further studies on all the species of Elephantulus could provide new evidence for assessing the relationships within this clade, including Macroscelides that by the present analysis appeared as a well-distinguished taxonomic entity.
Nest site preference of common dormouse was studied in two different habitat types of central Italy: a mesophilous deciduous forest dominated by Fagus sylvatica, and a thermophilous deciduous oak wood with Quercus cerris and Q. pubescens. In each site, 50 nest boxes were fixed to trees and monitored monthly for two years (May 1998-April 2000. Moreover, in both study sites, 19 habitat variables were measured within a 3-m radius circular plots centred on each nest box. We hypothesised that specific habitat features may induce common dormice to choose a particular site for nesting. Therefore, we compared habitat variables, recorded at the neighbourhood of either occupied or unoccupied nest boxes, in order to identify the importance of factors in nest site preference. In both beech and oak woodlands, the choice of nest site was affected by understorey vegetation structure rather than species diversity. In particular, the common dormouse prefers sites with high understorey density probably for the presence of route-ways through branches and visual protection from predators.
This is the first mitochondrial phylogeography of the common dormouse, Muscardinus avellanarius (Linnaeus, 1758), a hibernating rodent strictly protected in Europe (Habitat Directive, annex IV; Bern Convention, annex III). The 84 individuals of M. avellanarius, sampled throughout the distributional range of the species, have been sequenced at the mitochondrial DNA gene (cytochrome b, 704 base pairs). The results revealed two highly divergent lineages, with an ancient separation around 7.7 Mya and a genetic divergence of 7.7%. Lineage 1 occurs in Western Europe (France, Belgium, and Switzerland) and Italy, and lineage 2 occurs in Central–Northern Europe (Poland, Germany, Latvia, and Lithuania), on the Balkan Peninsula, and in Turkey. Furthermore, these two lineages are subdivided into five sublineages genetically isolated with a strong geographical association. Therefore, lineage 1 branches into two further sublineages (Western European and Italian), whereas lineage 2 contained three sublineages (Central–Northern European, Turkish, and Balkan). We observed low genetic diversity within the sublineages, in contrast to the significant level of genetic differentiation between them. The understanding of genetic population structure is essential for identifying units to be conserved. Therefore, these results may have important implications for M. avellanarius conservation. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 648–664.
The seasonal activity of the common dormouse Muscardinus avellanarius was studied in three different habitat types of central Italy: a deciduous beech wood dominated by Fagus sylvatica (Cimini Mountains), and a deciduous oak woodland with Quercus cerris and Q. pubescens and an evergreen wood dominated by holm oak Q. ilex, both along the central Tyrrhenic coast. In each site, 50 nest-boxes were fixed to trees and were monitored monthly for 2 years (May 1998-April 2000. In the beech wood site, the species showed an annual biological cycle similar to that described for populations of central and northern Europe: dormancy in winter, from the first 10 days of November to the end of December; end of hibernation in the first half of April; reproduction between May and July. On the contrary, in the two coastal sites, nest-boxes were occupied from October to June, and the breeding period was in autumn, showing that a winter dormancy phase is absent, probably owing to the mild winter. On the other hand, no dormice or new nests were observed in nest-boxes in summer suggesting that a dormancy phase occurred in summer, probably owing to dry climatic conditions. Two patterns of biological cycle therefore emerged from the results: a temperate pattern in beech forest with winter dormancy and spring reproduction, and a Mediterranean pattern in coastal habitats with autumnal reproduction, winter activity and summer dormancy.
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