Evolutionarily Significant Units of Gray-Sided Vole (Myodes rufocanus) in Hokkaido, Japan


Anna Pauline O. de Guia1 and Takashi Saitoh2

1Animal Biology Division, Institute of Biological Sciences, College of Arts and Sciences, University of the Philippines Los Baños, Laguna 4031, Philippines
2Field Science Center, Hokkaido University, Kita 11 Nishi 10,
Sapporo 060-0811, Hokkaido, Japan

corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.



The gray-sided vole, Myodes rufocanus (= Clethrionomys rufocanus) is a widespread species in Hokkaido, Japan. We applied an integrative approach to determine adaptive and neutral genetic variation in the gray-sided vole populations to identify full or partial Evolutionarily Significant Units. We surveyed 38 mainland populations and six island populations. The mitochondrial DNA control region was analyzed for neutral genetic variation and cranial measurements were taken as a proxy for adaptive variation. Data on neutral genetic variation indicate that most island populations are differentiated from the mainland populations. The islands of Teuri and Yagishiri, Rishiri and, Kunashiri can be regarded as partial ESUs based on their unique haplotypes. Partial ESUs based on morphological features can be identified in the eastern part of mainland with populations from Akkeshi and Shibecha. A full ESU designation can be given to Daikoku Island based on its unique haplotype and unique morphological feature.



Variability in any trait is expected to be spatially structured even in widespread species of animals due to several physical and ecological barriers that isolate populations. Variation in these populations can be recognized based on neutral genetic variation (Moritz 1994a) and adaptive . . . . . . . . .





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