Mitochondrial DNA evidence for late Pleistocene population expansion of the white catfish, Ameiurus catus

作者：Padhi Abinash^*

来源：Biochemical Systematics and Ecology, 2012, 42: 94-98.

DOI：10.1016/j.bse.2012.02.011

• White catfish
• mtDNA
• Genetic diversity
• Bayesian skyline
• Quaternary period
• Demographic history

Employing distance-based, maximum likelihood-based, and Bayesian coalescent methodologies and utilizing mitochondrial control region sequence data, the present study reports the importance of Pleistocene glacial epochs on the demographic expansion of the white catfish, Ameiurus catus. White catfish are endemic to the southeastern region of the United States, the region that had never glaciated during the Pleistocene epoch; however, compared to the present day meandering river patterns, the region did exhibit braided river patterns during the late Quaternary. The present study revealed the existence of two distinct matrilineal lineages of white catfish, southeast Gulf coast (SEGC) and southeast Atlantic coastal plains (SEACP), which are estimated to have diverged from their common ancestor approximately 0.71 (0.37-1.1) million years ago. Consistent with the results of the mismatch distribution and site frequency spectrum based summary statistics such as Fu's F, the Bayesian skyline plot (BSP) has also showed evidence for population expansion. The BSP showed two phase growth: a static phase until 0.2 million years, followed by a sudden population expansion thereafter, which is the time that coincides with the late Quaternary epoch. The changing patterns in drainage systems in response to the Quaternary climate change might have had a significant impact on the demographic expansion of white catfish.

• 出版日期2012-6