Figure 2 in The common bottlenose dolphin (Tursiops truncatus) ecotypes of the western North Atlantic revisited: an integrative taxonomic investigation supports the presence of distinct species

Figure 2. Traditional morphometric analyses of bottlenose dolphins of the western North Atlantic. A, scatter plot of the principal component 1 (PC1) and 2 (PC2) scores from the analysis of 25 cranial variables and 147 samples. Ellipses correspond to the 95% confidence interval. The shape of the data points represents the ecotype (coastal or offshore) as defined based on random forest (RF) results. The colour of the data points represents the clustering classifications according to density clustering (DC) results: black, samples follow the same classification (coastal or offshore) as RF and the a priori stratification; orange, 'cluster-3' identified only by DC (see main text). B, violin plot of the total external body length (TL) differentiated per sex (F, female; M, male) and ecotype.