Genetic diversity variation among age groups
SRS predicts low and possibly variable genetic diversity in juveniles but at the same time high and uniform genetic diversity in adults, because of summation of multiple recruitment events. The null hypothesis would have no difference in genetic diversity between any pop:age groups. What we observed did not conform to either of these hypotheses: in our case, we detected small (on the order of 2% of the global mean of 0.005) but significant variation in genetic diversity between all pop:age groups (Fig. 1F). Compared to adults from the same site, juveniles were significantly less diverse at Goofnuw Channel (GC) and especially at Nimpal (NMP), as SRS would predict; however, they were more diverse at the South Tip (ST) and the West Outer Reef (WOR). Moreover, adults also appeared to vary in genetic diversity across sites (Fig. 1F). To check if all this variation was somehow an artifact of our workflow, we have randomized the content of pop:age groups before computing per-group genetic diversity; none of the randomized comparisons were significant.