Figure 2 . Overview of the data and summary of hypothesis 1 on differences in species richness across beach levels. A . Overview of a Monocelididae, as a representation of a typical proseriate flatworm. The main internal and external structures that considered in the analyses are marked. B. Distribution of the sampled beaches in the Western Mediterranean, with latitude and longitude reported as WGS84 reference coordinates. The size of the circle is proportional to the total number of species found in each beach (see box). C.Box plot showing the distribution of the number of species in each sample, divided by beach level. Each value is jittered vertically (and to a minimum extent also horizontally) to allow a visualization of sample size. The non-independence of the data is accounted for in the model, and the plot with the identity of the beach for each dot is shown in Supplementary Figure S1.