Figure 3.

Habitat and rhythms of S. roscoffensis. A-B: Shallow coastal areas in Roscoff (France) during high and low tide periods, either covering or exposing the natural habitat of S. roscoffensis. C: During normal tide fluctuations over 24-hour periods (blue line), S. roscoffensis migrate to the surface of the sand or stay burrowed during low and high tides, respectively (red line). This process is dependent on the presence of sunlight (yellow line). D: In summer months, when long days overlap two low tide periods, S. roscoffensis migrate twice a day to expose themselves to sunlight. (C, D: after ⁸⁸).