Sea Urchins

Strongylocentrotus  purpuratus

On the field trip I got the chance to touch a sea urchin.  Sea urchins live on rocky shores and the bottom of the ocean floors.  The domain is Eukarya, the kingdom is Animalia, the phylum is Echinodermata, the class is Echinoidea, the order is Camarodonta, the family is Echenique,  the genus is Strongylocentrotus, and the species is Purpuratus.  Sea urchins are heterotrophs endothermic, and have radial symmetry.  Sea urchins have long spikes, hard chalky plates, and tiny tubed feet. 

There are over 700 different species of sea urchins.  A structural adaptation is that sea urchins have long spikes to scare off predators. Some species are poisonous to also scare off predators, and sea urchins have tiny tube feet in order to move around.  A sea urchin's diet is kelp, algae, dead fish, sponges, mussels, and barnacles.  Sea urchins are eaten by crabs, sunflower stars, people, birds, fish, sea otters, and snails.  Sea urchins are also found in sushi dishes!