Study of morphological variations between Pacific herring Clupea pallasii and Atlantic herring Clupea harengus

Abstract:

Twenty-three morphological parameters were analyzed using ANOVA, cluster analysis and discriminant analysis to study the morphological variations between Clupea pallasii and Clupea harengus. ANOVA results showed that there were extremely significant differences (P<0.001) in the means of 14 morphological parameters, greater variance between populations than within populations. Cluster analysis suggested that all of the 82 samples were divided into two clusters. Discriminant analysis based on 23 parameters showed that there were extremely significant differences between the two species (P<0.001); discriminant analysis with 11 selected parameters gave a discriminant formula with accuracy of 100%. However, the coefficients of difference of 23 parameters suggested that the differentiations between the two species were still under the level of different geographic populations within species according to Mayr’s 75% Rule. We postulated that the small scale divergence in morphology between the two species might be caused by a recent separation and similar ecology environment.