Sexual size and heterochronic dimorphism indexes. The sexual size dimorphism index (SSD I PC1 = female PC1 - male PC1) and the heterochronic size dimorphism index (HSD I PC1 = metamorph PC1 - paedomorph PC1). Values are means ± SE, derived from the distribution of 1000 bootstrap estimates. Full bars: the alpine newt Mesotriton alpestris; open bars: the palmate newt Lissotriton helveticus; grey bars: the smooth newt L. vulgaris, met = metamorphs, paed = paedomorphs, and J. = Jezero (lake). See Table 2 for the results of the statistical tests.