The job of the pivot table is to summarize your source data table based on the criteria you specify in the filter fields (Report Filter, Column Labels, and Row Labels). You can think of it as a very advanced way to arrange and filter your data.
The Limulidae are the only recent family of the order Xiphosura, and contain all four living species of horseshoe crabs: 1  Carcinoscorpius rotundicauda, the mangrove horseshoe crab, found in Southeast Asia. 2  Limulus polyphemus, the Atlantic horseshoe crab, found along the American Atlantic coast and in the Gulf of Mexico.
Horseshoe crabs have a wide range of food resources. As said before, horseshoe crabs are secondary consumers. They mainly consume a wide variety of mollusks. They feed upon many species of bivalves and lots of different clams.Clams include the surf clam, macoma clam, blue mussel, wedge clam, razor clam, fragile razor clam, and soft-shelled clams.They also eat different kinds of worms. Not only do they consume animals, vascular plant material has often been found in sampled horseshoe crabs.lams include the surf clam, macoma clam, blue mussel, wedge clam, razor clam, fragile razor clam, and soft-shelled clams. They also eat different kinds of worms. Not only do they consume animals, vascular plant material has often been found in sampled horseshoe crabs.