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Tashima S.,Hokkaido University | Kaneko Y.,Tokyo University of Agriculture and Technology | Baba M.,Kitakyushu Museum of Natural History and Human History | Yachimori S.,Shikoku Institute of Natural History | And 3 more authors.
Mammal Study | Year: 2011

The short interspersed nucleotide elements (SINEs) are specific to the taxa and thought to be one of powerful phylogenetic gene markers. Especially, the SINE sequences, which exist uniquely in genome of order Carnivora, are named CAN-SINEs. Among the Eurasian badgers (genus Meles), a member of the family Mustelidae in order Carnivora, the Japanese badger (M. anakuma) was previously reported to have an insertion of CAN-SINE in the final intron of the zinc finger protein gene on Y chromosome (ZFY). In the present study, we examined occurrence of the CAN-SINE of the ZFY final intron in the Eurasian badgers, and three continental and four Japanese haplotypes were identified from a total of 40 male badgers. Among the Eurasian badger CAN-SINEs, a 12-bp deletion specific to the Japanese haplotypes was found, whereas the 12-bp region (non-deletion) in the continental haplotypes consisted of one 6-bp direct repeat and 6-bp microsatellite-like sequences. Moreover, the continental haplotypes were phylogenetically divided into three lineages: eastern Eurasia, Caucasus and western Eurasia. These genetic differentiations supported the classification recently proposing that genus Meles are grouped into the European badger (M. meles), the Southwest Asian badger (M. canescens), the Northwest & Central Asian badger (M. leucurus) and the Japanese badger (M. anakuna). In addition, the number of adenines in the poly A/T rich tails was polymorphic among all lineages of Eurasian badgers, and geographically variable within the Japanese badgers. © the Mammalogical Society of Japan. Source

Inoue T.,Hokkaido University | Kaneko Y.,Tokyo University of Agriculture and Technology | Anezaki T.,Gunma Museum of Natural History | Yachimori S.,Shikoku Institute of Natural History | And 6 more authors.
Conservation Genetics | Year: 2012

The masked palm civet Paguma larvata (Carnivora: Viverridae) in Japan has been phylogeographically considered an introduced species from Taiwan. To reveal the population structures and relationships among the P. larvata populations in Japan, seven compound microsatellite loci were isolated from the genome and genotyped for 287 individuals collected from the field. STRUCTURE analysis and factorial correspondence analysis of genotyping data revealed that animals from Japan were divided into four genetic clusters. Geographic distribution of the genetic clusters partly referred to sampling areas, indicating multiple introductions into distinct areas of Japan or independent founding events leading to the generation of different genetic clusters within introduced populations in Japan. The large genetic differentiation of populations in the Shikoku District from those in other areas within Japan suggests that there were at least two introduction routes into Japan, and a possibility that some founders from areas other than Taiwan were also involved in the introduction into Japan. The genetic variation within Japanese populations were not markedly reduced compared with that of Taiwan. The results indicated that the Japanese populations of P. larvata could have retained moderate genetic diversity during founding events, because of multiple introductions, or a large number or high genetic diversity of founders. Although some individuals in Japan showed a sign of admixture between different clusters, there is no evidence that such an admixture markedly increased the genetic diversity within Japanese populations. © 2012 Springer Science+Business Media B.V. Source

Masuda R.,Hokkaido University | Lin L.-K.,Tunghai University | Pei K.J.-C.,National Pingtung University of Science and Technology | Chen Y.-J.,CSIC - National Museum of Natural Sciences | And 5 more authors.
Zoological Science | Year: 2010

The source areas of the Japanese populations of the masked palm civet Paguma larvata (Viverridae, Carnivora), an alien species in Japan, have not been identified. In the present study, to reveal their origins and genetic features, we determined the full mitochondrial DNA cytochrome b sequences (1,140 base-pairs) of a total of 206 individuals of P. larvata from the Honshu and Shikoku islands of Japan (186 animals) and Taiwan (20 animals), and investigated their molecular phylogeography and the genetic relationships between populations in these countries. We found that each animal from Japan exhibited one of four haplotypes (JA1, JA2, JA4, and JA5), and that JA1 and JA4 were more frequent in eastern Honshu and Shikokucentral Honshu, respectively. By contrast, six haplotypes consisting of four new types (TW1, TW2, TW3, and TW4) and the previously reported two types (JA1 and JA4) were identified from 20 animals from native populations in Taiwan. Within Taiwan, one haplotype set (JA1, TW1, and TW2) was distributed in the western region, while a second (JA4, TW3, and TW4) was found in the eastern region; these regions are separated by high mountain ranges. Our comparison of haplotype distributions strongly demonstrated that the eastern Japanese populations originated from animals of western Taiwan, and that the western Japanese populations originated from those of eastern Taiwan. In addition, the lower genetic variability and particular distribution patterns of haplotypes in Japan showed founder effects, which may have resulted from multiple introductions of P. larvata to Japan from Taiwan. © 2010 Zoological Society of Japan. Source

Tashima S.,Hokkaido University | Kaneko Y.,Tokyo University of Agriculture and Technology | Anezaki T.,Gunma Museum Natural History | Baba M.,Kitakyushu Museum of Natural History and Human History | And 2 more authors.
Mammal Study | Year: 2010

To further understand the population structures of the Japanese badgers (Meles anakuma) on the Japanese islands, we analyzed their bi-parentally inherited microsatellites. Based on genotypes of nine microsatellite loci, the badgers were divided into five discrete clusters: three clusters from the Honshu Island, one from Kyushu and one from Shikoku. We propose that this genetic differentiation among badgers from the Honshu, Shikoku and Kyushu Islands is as a consequence of geographical isolation caused by the Seto Inland Sea. Furthermore, the cluster containing individuals from Shikoku was more differentiated from the other clusters, plausibly attributable to the earlier geological separation of the Shikoku Island from the Honshu and Kyushu Islands. The three clusters in Honshu, however, did not correspond precisely with geographical locations. As indicated in previous studies, based on mitochondrial DNA analysis, the genetic relationships within the Japanese badgers might reflect recent population expansion, occurring over a relatively short evolutionary time-scale. The findings preliminarily indicate that the Japanese badgers do not possess the high levels of philopatry seen in the European badger (Meles meles), a closely related species, although further analyses using balanced sample sizes from a wider range is required. © 2010 the Mammalogical Society of Japan. Source

Hoshino K.,Oita Marine Palace Aquarium UMITAMAGO | Hibino Y.,Mie University | Kimura S.,Mie University | Machida Y.,Kochi University | Machida Y.,Shikoku Institute of Natural History
Ichthyological Research | Year: 2011

The worm eels, Muraenichthys okamurai Machida and Ohta 1996 and M. borealis Machida and Shiogaki 1990, both from Japanese waters, have been distinguished by the difference in dentition on the upper jaw and palatal area, and regarded as valid species of Scolecenchelys. A detailed examination of the dentition of the type specimens and recently caught specimens revealed that the difference in the dentition described in the original descriptions is actually intraspecific variation. Apparently M. okamurai represents the juvenile of M. borealis, and the former is its junior subjective synonym. © 2011 The Ichthyological Society of Japan. Source

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