This suggests unidirectional migration in the latter case. Multiple runs showed consistent results, and the 95% CIs suggested that the data contained sufficient information for reliable migration rate estimates. In total, 180 Cytb sequences (1,120 bp) were analyzed, including short- and long-beaked common dolphins from the Atlantic and Pacific Oceans. Twenty-five haplotypes were identified amongst the 40 New Zealand common dolphin sequences analysed. No shared haplotypes between New Zealand common dolphins

and either short- or long-beaked common dolphins from other regions were found. The Tamura-Nei nucleotide substitution model was the best-fitting model identified by Modeltest for this data set. The Bayesian phylogenetic Trametinib order tree obtained showed several clades strongly supported by high posterior probability values (Fig. 5). However, these clades fail to show any geographical

or taxonomic association, with New Zealand common dolphin haplotypes dispersed throughout the tree. Most New Zealand haplotypes clustered with short-beaked common dolphins from the Pacific and Atlantic Oceans, although some clustered with long-beaked common dolphins from eastern North Pacific and from eastern South Atlantic (Fig. 5). Both long-beaked common dolphin populations do not form monophyletic lineages. Our results showed high genetic variability among the New Zealand common dolphins at both mitochondrial and find more nuclear markers, comparable to values reported for other common dolphin populations (Natoli et al. 1987,

Viricel et al. 2008, Mirimin et al. 2009, Amaral et al. 2012). Both gene and nucleotide diversities based on the mtDNA control region, and HO and HE based on the microsatellites were high for the three click here putative populations considered. Furthermore, throughout their geographic range, Delphinus exhibit relatively low genetic differentiation compared to other closely related taxa with similar geographical distribution (e.g., Tursiops truncatus; see Natoli et al. 2004). This can be expected if we consider that common dolphins are a panmictic species and show high levels of mobility across their habitat (Evans 1971). However, populations residing at the peripheral species’ range are generally characterized by lower genetic diversity and higher genetic differentiation (Eckert et al. 2008), and the pattern observed for the New Zealand common dolphins is more typical of a central population. Mitochondrial DNA data also provide evidence to suggest that the New Zealand population has undergone expansion, as shown by the neutrality test and the mismatch distribution results. Typically, populations characterized by high levels of haplotypic diversity are large and widely distributed. The high number of unsampled/extinct haplotypes detected by the Network analysis (Fig. 2) may indicate that our sampling failed to sample all the variability present in the population.

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