Barnacles are small aquatic creatures found in many parts of the world. They belong to a group of organisms known as crustaceans, and are related to crabs, shrimps and lobsters. Barnacles have several unique characteristics that make them interesting to study. Most barnacle species live attached to hard surfaces such as rocks or ships' hulls by means of a cement-like substance secreted from their bodies. The most common barnacle is the acorn barnacle, which can be found on rocks around the shoreline and even in deeper water habitats. Humans use these crustaceans for various purposes ranging from producing seafood dishes to researching ocean chemistry.

Biology of Barnacles

Barnacles are generally small, between 1-2 cm in size, and have an exoskeleton made of calcium carbonate. Depending on the species, they can be oval or conical in shape. The body is divided into two parts: a head region called the capitulum and a foot that serves as an attachment organ for adhering to hard surfaces such as rocks and boats. Barnacles also have two pairs of antennae used for sensing their environment and five pairs of thoracic appendages which act as gills to obtain oxygen from water.

Barnacles feed by filtering food particles out of seawater using their specialized feeding appendages called cirri; these bristle-like structures wave around searching for nutrients such as algae, diatoms or zooplankton. Once found, particles are drawn up through the barnacle’s mouth where digestion occurs before being expelled back into the water column. In addition to this filter-feeding method, some barnacle species supplement their diet by scavenging organic matter from other organisms or preying on smaller invertebrates like copepods or bivalves.