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Vol. 46 No. 6, 2007
Population Structure and Historical Demography of the Spotted Mackerel (Scomber australasicus) off Taiwan Inferred from Mitochondrial Control Region Sequencing
Tzong-Der Tzeng
College of Liberal Education, Shu-Te University, 59 Hun Shan Rd., Hun-Shan Village, Yen-Chau, Kaohsiung County 824, Taiwan
Tzong-Der Tzeng (2007) The strong debate as to whether or not the spotted mackerel (Scomber australasicus)
off Taiwan is genetically structured continues. Sequence analyses of
the complete mitochondrial DNA control region (886 bp in length) were
conducted to elucidate the population structure and historical
demography of spotted mackerel off Taiwan. In total, 157 individuals
were separately collected from the East China Sea (ECS), waters off
Ilan (ILAN, northeastern Taiwan), Taitung (TT, southeastern Taiwan),
and Linyan (LY, southern Taiwan), and the South China Sea (SCS), and
132 haplotypes were obtained. The haplotype diversity (h) was high for all samples (99.6%), with values from 99.1% (ECS) to 99.8% (SCS). Nucleotide diversity (π)
was low for all samples (0.70%), with values from 0.61% (LY) to 0.75%
(ILAN). A median-joining network of 132 haplotypes revealed no
significant phylogeographic structure. Analysis of molecular variance
(AMOVA) and spatial analysis of molecular variance (SAMOVA) indicated
no significant heterogeneity. FST
values indicated no significant difference in each pairwise combination
of these 5 sampled areas except the one between the ECS and SCS
samples. These results suggest that spotted mackerel off Taiwan belong
to the single gene pool. Both mismatched distribution analysis and
neutrality tests suggested that spotted mackerel in these waters have
experienced population expansion since the late Pleistocene
(approximately between 46,399 and 8,980 yr ago).
Key words: Mitochondrial control region, Scomber australasicus, Population structure, Population expansion.
*Correspondence: Tel: 886-7-6158000 ext. 4211. Fax: 886-7-6158000 ext. 4299. E-mail:tdtzeng@mail.stu.edu.tw
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