Images of collected samples (IMAGE) Toho University Caption (A) Reduced mud (marked by red dashed lines) is a black sediment with high viscosity scattered over a large area of the tidal flat. (B) A mound of fecal pellets of Marphysa sp. E excreted on the surface of the tidal flat. Credit Dr. Atsuko Nishigaki Usage Restrictions None License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.