Fig. 9. Variation, as a function of year, of the mean and standard error of head width (KB) of males found dead at the Jagersveld CMR site. Numbers indicate the size of the samples, and letters and colors indicate samples not significantly differing in size from each other at the P = 0.05 threshold, by using the non-parametric Kruskal-Wallis test for multiple comparisons. Samples of years 1924 and 2021 were excluded from the K-W analysis.