Differences in community structure between samples separated by different geographic distances and seasons.

<p>Bray-Curtis dissimilarity = 1 indicates that communities are very different, whereas Bray-Curtis dissimilarity = 0 indicates that communities are very similar. Each marker was studied using three restriction enzymes; only one is depicted here (and its name is given in parentheses), but for each marker, the overall pattern was very similar using the other two restriction enzymes (data not shown). Different letters indicate significant groupings. Bet., between.