| Summary: | 碩士 === 東海大學 === 生物學系 === 91 === Abstract
Squirrels belonging to the genus Callosciurus are widely distributed in Southeast Asia are classified into 15 species. In Taiwan, the population of C. erythraeus is divided into three subspecies (C. e. thaiwanensis, C. e. centralis and C. e. roberti) based on ventral pelage color patterns. To resolve the subspecific status and phylogenetic relationships of C. erythraeus of Taiwan, the molecular and morphological methods were used. The mitochondrial DNA control region sequences (1,079-1,081 bases) of C. erythraeus were determined for 70 specimens from 29 locations in Taiwan. Phylogenetic relationships reconstructed by neighbor-joining method indicated that the Taiwan population is separated into three major lineages: East Taiwan and Hengchun Peninsula (Group 1), Southwest Taiwan (Group 2) and Northwest Taiwan (Group 3). The haplotype diversity and nucleotide diversity of three lineages were 0.945-0.964 and 0.71-1.32%, respectively. The mean genetic distance among three lineages was similar (0.0261-0.0272), and the nucleotide divergence among them was also similar (2.51-2.61%). The fixation index (Fst) and gene flow (Nm) values indicate some gene flow between Groups 1 and 2, but relatively few between Groups1 and 3 or Groups 2 and 3. The morphometric differences of skulls among three lineages were not significantly separated based on principal component analysis and canonical discriminant analysis. Two or three ventral pelage color patterns were found in each lineage. The Central Mountain Range, the Choshui River and the Lanyang River probably play important roles in the geographic isolation of the C. erythraeus populations in Taiwan. At least two major glacial refugia of C. erythraeus might have been formed in central and southeast Taiwan was discussed.
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