Hystrx It. J. Mamm . (n.s.) Supp. (2007) V European Congress of Mammalogy RODENTS AND LAGOMORPHS 51 Hystrx It. J. Mamm . (n.s.) Supp. (2007) V European Congress of Mammalogy 52 Hystrx It. J. Mamm . (n.s.) Supp. (2007) V European Congress of Mammalogy A COMPARATIVE GEOMETRIC MORPHOMETRIC ANALYSIS OF NON-GEOGRAPHIC VARIATION IN TWO SPECIES OF MURID RODENTS, AETHOMYS INEPTUS FROM SOUTH AFRICA AND ARVICANTHIS NILOTICUS FROM SUDAN EITIMAD H. ABDEL-RAHMAN 1, CHRISTIAN T. CHIMIMBA, PETER J. TAYLOR, GIANCARLO CONTRAFATTO, JENNIFER M. LAMB 1 Sudan Natural History Museum, Faculty of Science, University of Khartoum P. O. Box 321 Khartoum, Sudan Non-geographic morphometric variation particularly at the level of sexual dimorphism and age variation has been extensively documented in many organisms including rodents, and is useful for establishing whether to analyse sexes separately or together and for selecting adult specimens to consider for subsequent data recording and analysis. However, such studies have largely been based on linear measurement-based traditional morphometric analyses that mainly focus on the partitioning of overall size- rather than shape-related morphological variation. Nevertheless, recent advances in unit-free, landmark/outline-based geometric morphometric analyses offer a new tool to assess shape-related morphological variation. In the present study, we used geometric morphometric analysis to comparatively evaluate non-geographic variation in two geographically disparate murid rodent species, Aethmoys ineptus from South Africa and Arvicanthis niloticus from Sudan , the results of which are also compared with previously published results based on traditional morphometric data. Our results show that while the results of the traditional morphometric analyses of both species were congruent, they were not sensitive enough to detect some signals of non-geographic morphological variation. For example, while one series of analysis could detect the presence of sexual dimorphism, the other could not. These results highlight the importance of the need for a careful evaluation of size- and shape-related non- geographic mophological variation prior to subsequent analyses of geographic variation and the delineation of species. Erroneous analysis of non-geographic variation may also have implications in the interpretation of evolutionary and geographic processes that may be responsible for morphological differences at both the inter- and intra-specific levels. 53 Hystrx It. J. Mamm . (n.s.) Supp. (2007) V European Congress of Mammalogy PHYLOGENY AND HISTORICAL DEMOGRAPHY OF ECONOMICALLY-IMPORTANT RODENTS OF THE GENUS ARVICANTHIS (MURIDAE) FROM THE NILE VALLEY: OF MICE AND MEN E. H. ABDEL-RAHMAN AHMED 1, J-F. DUCROZ 2, A. MITCHELL 3, J. LAMB 4, G. CONTRAFATTO 4, C. DENYS 2, E. LECOMPTE 2 AND P. J. TAYLOR 5* 1 Sudan Natural History Museum, Faculty of Science, University of Khartoum P. O. Box 321 Khartoum, Sudan 2 Muséum National d'Histoire Naturelle, Department Systematics & Evolution, UMRCNRS 5202, Paris, France 3 Genetics Department, University of KwaZulu-Natal, Pietermaritzburg Compus, Private Bag X01, Scottsville, 3209, South Africa 4 School of Biological and Conservation Sciences, University of KwaZulu-Natal, P. O. Box 18091, Dalbridge, 4014, South Africa 5 Durban Natural Science Museum, P. O. Box 4085, Durban, 4000, South Africa *Corresponding author. e-mail: [email protected] Our investigation clarified the taxonomy, phylogeny and historical demography of semi- commensal Nile rats ( Arvicanthis ) from the Nile Valley in Sudan. Nile rats are important crop pests and zoonotic disease reservoirs; whilst not occupying human dwellings they are closely associated with agricultural settlements in the Nile Valley. Phylogenetic analysis of the complete cytochrome-b gene (1140 bp) of 23 individuals from six localities in Sudan (from two previously recognized species, A. niloticus and A. testicularis ), together with available Genbank sequences, supported the monophyly of the genus Arvicanthis and its sister-group relationship with Lemniscomys . The data supported the existence of only a single species, A. niloticus , from the Nile Valley. Historical demography and population genetics of the Sudanese Nile Valley population indicated a very recent exponential population expansion event ( ca 300 years ago), which corresponds with the most recent period of exponential human population expansion in the Nile Valley inferred from archaeological evidence. Two African Arvicanthis clades were supported (with 100% bootstrap support) by the broader phylogenetic analysis: 1) A. niloticus , A. abyssinicus and A. neumanni , and 2) A. rufinus and A. ansorgei from Western Africa. Within the first clade, divergence between lineages of A. niloticus s. s. from West and North-East Africa (8.9%) suggests specific recognition, but sampling of geographically intermediate localities is required. Based on hypothesized palaeodrainage and palaeoclimatic patterns, we propose a simple model for speciation of Arvicanthis in Africa. 54 Hystrx It. J. Mamm . (n.s.) Supp. (2007) V European Congress of Mammalogy APPLICABILITY OF DIFFERENT DNA-MARKERS TO THE RECOVERY OF PHYLOGENIES AT A DIFFERENT TAXONOMIC LEVEL: CASE STUDY OF SUBFAMILY ARVICOLINAE (CRICETIDAE, RODENTIA) NATALIYA ABRAMSON, ALEXEY KOSTYGOV Zoological Institute RAS. Universitetskaya nab.1, Sankt-Petersburg, Russia, 199034 e-mail: [email protected] Application of molecular markers became the most popular method in the studies of phylogeny and systematics of various organisms. However, the adequate choice of a molecular marker in correspondence with taxonomic level of the group under study rarely deserves a special attention. We compare the resolving power and limitations of mtDNA (cyt b) and nuclear (LCAT, GHR, p53, Fbgb) markers for the recovery of phylogeny at different taxonomic levels within subfamily Arvicolinae. A wide range of data sets (morphological, palaeontological, cytogenetic and others) was already applied to the study of phylogenetic relationships of the main phyla within the group. It makes this subfamily and ideal model for testing hypothesis on applicability of various DNA - markers to the recovery of phylogeny due to the possibility of cross-validation. Despite the good support of some clades, the basal splits both as within the most speciose genus Microtus and within subfamily in a whole remain uncertain. Molecular studies with the application of cyt b as a marker both to the recovery of phylogenetic structure in Microtus and the subfamily did not clarify the situation and "hard" polytomies" in both cases were explained by several pulses of rapid radiation. We argue that these polytomies are evident result of mutational saturation, accelerated and uneven rate of cyt b evolution resulting in high degree of homoplsy. It is especially evident in the case of M. gregalis . We studied variation of this marker in this species within the different isolated parts of its range and our results demonstrate extremely high variation and high rate of it evolution. Comparison of the cyt b trees and trees obtained from the analysis of nuclear markers showed that the latter gave much better resolution than the cyt b. Moreover phylogenies obtained from nuclear markers are in better agreement with a number of other data sets and confirmed the earlier findings of cytogenetic, biochemical and paleontological research. The LCAT appeared to be most appropriate marker for the study of phylogenies at the supraspecies level and p53 - for the the close species and species groups. GHR gives good resolution for the order of divergence at generic level. According to our findings the cyt b is an appropriate marker for the study of intraspecies (phylogeography) and species level phylogenies in Arvicolinae. The work was financially supported by RFBR grant No 06-04-49294-a. 55 Hystrx It. J. Mamm . (n.s.) Supp. (2007) V European Congress of Mammalogy COMPARATIVE PHYLOGEOGRAPHY OF RED-BACKED VOLES IN RUSSIA WITH SPECIAL REFERENCE TO THE FORMATION OF SYMPATRIC ZONE IN BANK AND RUDDY VOLES (MYODES , CRICETIDAE, RODENTIA) NATALIA ABRAMSON, EKATERINA RODCHENKOVA Zoological Institute RAS. 199034, Universitetskaya nab.1, Sankt-Petersburg, Russia e-mail: [email protected] Bank ( Myodes glareolus ) and ruddy ( M. rutilus ) voles have wide overlapped ranges.. Despite the fact that these species split from a common ancestor not later than 2.5 Ма , they are very similar in morphology, behaviour and karyotypes. Sympatric zone of these species formed gradually with the bank vole dispersing to the north and east and ruddy vole westward. Up to now there are a lot of data concerning the history of distribution and genetic structure of bank vole in Europe but analogous data are lacking for the most part of the species range in Russia. We analyzed the variation of the cyt b (1000bp) in the bank vole from 32 sites (225 specimens) in central and northern parts of European Russia, Ural and Transural regions and in ruddy voles (51) from the same sites in sympatric zone. We found that part of the haplotypes of the bank vole cluster within the haplotypes of a ruddy vole, phenomenon of introgression that was known earlier. Further on we outlined in details the geographic zone of introgression and show its scale. We found populations of bank voles with both types of haplotypes and show that the zone of introgression do not completely coincide with sympatric zone of two species. All bank voles in Murmansk area and north Karelia have