Question

What is the attached conical shell on the Eccentric Sand Dollar, as mentioned in the description?

a. Another Eccentric Sand Dollar.
b. A barnacle, likely California Barnacle.
c. A sea urchin of a different species.
d. Fossilized remains of a different marine organism.

Answer 1

The attached conical shell on the Eccentric Sand Dollar is a barnacle, likely California Barnacle, and not a part of the Echinodermata phylum to which sand dollars belong.

Step-by-step explanation:

The attached conical shell on the Eccentric Sand Dollar, as mentioned in descriptions, is b. A barnacle, likely California Barnacle. Barnacles are arthropods that live in various marine environments and often attach themselves to hard surfaces, which can include other marine animals like the Eccentric Sand Dollar. While they may resemble the cone-shaped shells of limpets, barnacles are more closely related to shrimps and thus, to crabs. This relationship is in contrast to the Echinodermata phylum, which includes the Eccentric Sand Dollar along with starfish, sea urchins, and other radially symmetrical marine animals.