Maria Grazia Filippucci

Phylogeny of the genus Apodemus with a special emphasis on the subgenus Sylvaemus using the nuclear IRBP gene and two mitochondrial markers: cytochrome b and 12S rRNA.

Phylogenetic relationships among 17 extant species of Murinae, with special reference to the genus Apodemus, were investigated using sequence data from the nuclear protein-coding gene IRBP (15 species) and the two mitochondrial genes cytochrome b and 12S rRNA (17 species). The analysis of the three genes does not resolve the relationships between Mus, Apodemus, and Rattus but separates Micromys from these three genera. The analysis of the two mitochondrial regions supported an association between Apodemus and Tokudaia and indicated that these two genera are more closely related to Mus than to Rattus or Micromys. Within Apodemus, the mitochondrial data sets indicated that 8 of the 9 species analyzed can be sorted into two main groups: an Apodemus group, with A. agrarius, semotus, and peninsulae, and a Sylvaemus group, with uralensis, flavicollis, alpicola, sylvaticus, and hermonensis. The position of Apodemus mystacinus is ambiguous and might be either included in Sylvaemus or considered a distinct subgenus, Karstomys, more closely related to Sylvaemus than to Apodemus. Estimation of the divergence time for these taxa suggests a separation between 7 and 8 My ago for the three groups (mystacinus and the two subgenera Apodemus and Sylvaemus). Within each subgenus, divergence times are between 5.4 and 6 My for Apodemus and between 2.2 and 3.5 My for Sylvaemus and mystacinus.

So close and so different: comparative phylogeography of two small mammal species, the Yellow-necked fieldmouse (Apodemus flavicollis) and the Woodmouse (Apodemus sylvaticus) in the Western Palearctic region

In Europe, concordant geographical distribution among genetic lineages within different species is rare, which suggests distinct reactions to Quaternary ice ages. This study aims to determine whether such a discrepancy also affects a pair of sympatric species, which are morphologically and taxonomically closely related but which have slight differences in their ecological habits. The phylogeographic structures of two European rodents, the Yellow-necked fieldmouse (A. flavicollis) and the woodmouse (Apodemus sylvaticus) were, therefore, compared on the basis of mitochondrial DNA cytochrome b (mtDNA cyt b) sequences (965 base pairs) from 196 specimens collected from 59 European localities spread throughout the species distributions. The results indicate that the two species survived in different ways through the Quaternary glaciations. A. sylvaticus survived in the Iberian Peninsula from where it recolonized almost all Europe at the end of the last glaciation. Conversely, the refuge from which A. flavicollis recolonized Europe, including northern Spain, during the Holocene corresponds to the Italo-Balkan area, where A. sylvaticus suffered a serious genetic bottleneck. This study confirms that even closely related species may have highly different phylogeographic histories and shows the importance of ecological plasticity of the species for their survival through climate change. Finally, it suggests that phylogeographic distinctiveness may be a general feature of European species.

Karyotype and genetic evolution in speciation of subterranean mole rats of the genus Spalax in Turkey

Karyotype (2n) and allozyme diversity at 37 gene loci were determined in 69 subterranean mole rats in Turkey belonging to the two superspecies: the ancestor Spalax leucodon (n = 55; 20 populations) and the descendant S. ehrenbergi (n = 14: four populations. We identified remarkable variation of diploid chromosome numbers in the S. leucodon superspecies: 2n = 38, 40, 50, 54, 60 and 62; and in the S. ehrenbergi superspecies: 2n = 52, 56 and 58. Genetic diversity indices were low on average in both S. leucodon and S. ehrenbergi superspecies: Allele diversity, A = 1.081 and 1.074; polymorphism, P-50 0 = 0.077 and 0.068; heterozygosity, H = 0.038 and 0.027; and gene diversity, H = 0.038 and 0.034, respectively. H ranged from 0 in mesic or semimesic regions to 0.088 in arid Anatolia. We consider the populations with different diploid chromosome numbers, 2n, as good biological species. Karyotypic diversity may mark extensive ecological speciation. Nees genetic distances, D average 0.174, range 0.002 0.422) and ecogeographical criteria suggest that almost each population may represent a different biological species, but critical future testing is necessary to support this claim. Karyotypes and allozymes are nonrandomly distributed across Turkey, displaying remarkable correlations with climatic and biotic factors. Both 2n and H are significantly correlated with aridity stress (2n/rainfall. r = −0.74; P < 0.001), and in our region also with climatic unpredictability. These results support the niche-width genetic variation hypothesis in space and time. Climatic selection in Turkey appears to be a major architect of karyotype and genetic (allozyme) diversity and divergence in mole rat evolution, in both speciation and adaptation.

Evolutionary biology of the genus Apodemus Kaup, 1829 in Israel. Allozymic and biometric analyses with description of a new species: Apodemus hermonensis (Rodentia, muridae)

Abstract Allozymic and biometric analyses were conducted on 195 speci mens belonging to the genus Apodemus from Israel. Genetic varia tion and differentiation were investigated by means of electro‐phoretic analysis of 36 gene loci. The electrophoretic results, com bined with biometric analysis, indicated the existence of a new Apodemus species, A. hermonensis, for which a formal description is given. The most common species in Israel, after A. mystacinus, is A. flavicollis and not A. sylvaticus, as commonly believed. So far we have found no A. sylvaticus in Israel. A. hermonensis was found on Mount Hermon, at about 2000 m. The body and skull sizes are intermediate between those of A. microps and A. sylvaticus. Geneti cally, it is very close to A. flavicollis, from which it can be distin guished by one locus (Np) fixed for an allele never found in Israeli populations of A. flavicollis, and another locus which is partially discriminant (Ada). In both A. mystacinus and A. flavicollis, the Israeli populations...

Biogeography and taxonomy of Apodemus sylvaticus (the woodmouse) in the Tyrrhenian region: Enzymatic variations and mitochondrial DNA restriction pattern analysis

In the western Mediterranean area, the taxonomic status of the various forms of Apodemus sylvaticus is quite unclear. Moreover, though anthropogenic, the origins of the island populations remain unknown in geographical terms. In order to examine the level of genetic relatedness of insular and continental woodmice, 258 animals were caught in 24 localities distributed in Belgium, France, mainland Italy, Sardinia, Corsica and Elba. Electrophoresis of 33 allozymes and mtDNA restriction fragments were performed and a upgma dendrogram built from the indices of genetic divergence. The dendrogram based on restriction patterns shows two main groups: ‘Tyrrhenian’, comprising all the Italian and Corsican animals and ‘North-western’, corresponding to all the other mice trapped from the Pyrenees to Belgium. Since all the Tyrrhenian mice are similar and well isolated from their relatives living on the western edge of the Alpine chain, they must share a common origin. The insular populations are consequently derived from peninsular Italian ones. From a taxonomic point of view and taking the priority rules into account, we have to invalidate A. s. clanceyi Harrison, 1948 and to consider the Tyrrhenian woodmice as belonging to A. s. milleri de Beaux, 1926, whereas the North-western ones must be referred to as the nominal subspecies. As far as the Elban woodmouse is concerned, at the moment we prefer to keep its present subspecific status because we only studied one animal.

Evolutionary genetics and systematics of the garden dormouse, Eliomys Wagner, 1840 (Gliridae, Mammalia): 3. Further karyological data

Abstract The karyotypes of 12 specimens of dormice of the genus Eliomys, from the Alpine region of Switzerland and France, and from Israel (Negev Desert) were analyzed. In the Jura Mountain region, both in France (Besancon) and Switzerland (Canton of Vaud), the specimens were characterized by a diploid number: 2n = 50. In the dormice from the Canton of Valais, the karyotype was 2n = 54. These data contribute to complete the distributional map of the karyotypes in European populations of Eliomys quercinus. G‐banding analysis of the Israeli dormice, with 2n = 48, revealed for the first subtelocentric pair the same pattern as described in the European and African populations of Eliomjs. Therefore, this G‐pattern differs from that reported for animals collected in another locality of the Negev Desert (Israel).

Evolutionary genetics and systematics of the garden dormouse, Eliomys Wagner, 1840. 4 ‐ Karyotype and allozyme analyses of E. quercinus dalmaticus from Yugoslavia

Abstract The results of karyological and electrophoretic analyses of the garden dormouse, Eliomys quercinus dalmaticus, collected at two localities in Yugoslavia are reported. The karyotype consists of 48 chromosomes (FNa = 86). The chromosome morphology, as revealed by differential staining, is the same as in Eliomys quercinus pallidus from central Italy, but differs in two pairs of chromosomes from E. quercinus lusitanicus from Spain. Comparison between E. g. dalmaticus and other chromosomal races of the garden dormouse, by electrophoretic analysis of 41 gene loci, suggests a different origin for central European and Alpine populations

Allozyme variation and divergence in the phyllotine rodent Calomys hummelincki (Husson, 1960).

The aim of the present study was to assess the degree of genetic variation and divergence among six populations of Calomys hummelincki, a phyllotine rodent distributed in northern South America. With this information we will try to evaluate the two hypotheses of possible colonization and differentiation of this group of rodents postulated by Baskin and Reig. We studied 34 loci by electrophoretic analysis: 21 were monomorphic for all populations and 13 were polymorphic in at least one population, being P1% = 21.6% the mean value for all populations. The mean value of heterozygosity per locus was H = 0.075. Low values of genetic distance were observed among populations of the Llanos region (0.001 < D < 0.006). There was a larger genetic distance (D = 0.024) between the population from Isiro, in the northwestern semiarid region, and those from the Llanos region. The insular population of Aruba displayed the lowest value of genetic distance with the population from Isiro (D = 0.014). The specimens from Sipao, on the right side of the Orinoco river, displayed the highest values of genetic distances in comparison with other populations of C. hummelincki (0.070 < D < 0.095). The relatively high differentiation was due to the fixation of new alleles, not found in other populations of C. hummelincki, at loci Idh-1 and Est-2. F-statistics and Nm values indicated reduced gene flow among the populations sampled. Despite the limited data, the results seem to support Reigs hypothesis about south to north colonization of genus Calomys in South America.