Sea urchin
Sea urchins or urchins () are typically spiny, globular animals, echinoderms in the class Echinoidea. About 950 species live on the seabed, inhabiting all oceans and depth zones from the intertidal to . Their tests (hard shells) are round and spiny, typically from across. Sea urchins move slowly, crawling with their tube feet, and sometimes pushing themselves with their spines. They feed primarily on algae but also eat slow-moving or sessile animals. Their predators include sea otters, starfish, wolf eels, and triggerfish.
Peter Pritchard
Pritchard's most important and innovative work has been along the Atlantic coast of Guyana, the South American country that is home to four of the world's seven known sea turtle species: the leatherback, green, hawksbill and the olive ridley. By the 1960s, overhunting by local Arawak Indians — themselves an endangered group — had ravaged the turtle population.