Sea urchin science
Science activities are progressing well. The sea urchin species pictured below is a Sterechinus neumayeri and is an endemic Antarctic species, occurring mainly in shallow water around the whole Antarctic coast. This specimen was one of six found on the tide gauge by Doug, Ryan and Sam. On the underside of the specimen retractable tube feet and spines can be seen - a characteristic of most echinoderms. In the centre are five teeth that are used to scour hard substrates of micro algae. Sterechinus neumayeri is the species that will be used this season to study the effects of temperature changes and ocean acidification. When all soft tissues and spines are removed we have what the skeleton or "test" of a sea urchin Sterechinus neumayeri looks like. For some species, it is necessary to examine the surface to determine the sea urchin to species level. Here the tubercles, or small elevated bumps that carry the spines, can be seen in very ordered rows, and small pores that the tube feet emerge from, in ten separate columns. The five pores towards the centre are called gonopores, and are the only way to distinguish the sexes.