An aggregation of vestimentiferan tubeworms (Lamellibrachia sp.). Such aggregations provide habitat for many smaller animals such as the small white anemones covering the tubeworm tubes and the shrimps Alvinocaris muricola. The tiny white spots all around the tubeworms are copepods, tiny swimming crustaceans. These tiny, mobile animals could be an important link between primary productivity in the sediment and the sessile (unable to leave their location, permanently attached) anemones on the tubes. Image courtesy of the NOAA Okeanos Explorer Program.