Title: Evolutionary history and phylogenetic relationship between Auxis thazard and Auxis rochei inferred from COI sequences of mtDNA
Authors: Girish Kumar; Swaraj Priyaranjan Kunal; S.K. Shyama
Addresses: Biological Oceanography Division (BOD), National Institute of Oceanography (NIO), Dona Paula, Goa 403004, India ' Biological Oceanography Division (BOD), National Institute of Oceanography (NIO), Dona Paula, Goa 403004, India ' Department of Zoology, Goa University, Taleigao Plateau, Goa 403206, India
Abstract: Tunas of the genus Auxis are cosmopolitan species and the smallest members of the tribe Thunnini, the true tunas. In the present study, COI sequences of mtDNA were employed to examine the evolutionary history and phylogenetic relationship between A. thazard and A. rochei. A total of 29 COI sequences were retrieved from NCBI. Historic demographic analyses of sequence data showed that A. thazard has undergone sudden population expansion in the past while population size of A. rochei has been remain constant for long period. Non-significant value of Tajimas's D (P = 0.22400) and Fu's FS (P = 0.21400) test fail to reject the null hypothesis of neutral evolution for A. rochei. Phylogenetic analyses of nucleotide sequences demonstrated separate clusters for both species and are strongly supported by 98% bootstrap value. The results of the present study suggest the recent founding of A. thazard in world ocean while A. rochei represents the ancestral species.
Keywords: tuna; phylogenetic relationship; evolutionary history; population expansion; COI sequences; mtDNA; diagnostic markers; Auxis thazard; Auxis rochei; nucleotide sequences; bioinformatics.
International Journal of Bioinformatics Research and Applications, 2013 Vol.9 No.6, pp.604 - 613
Received: 12 Dec 2011
Accepted: 30 Apr 2012
Published online: 10 Aug 2013 *