This small squid is a new and important biomedical research model whose use has been limited by the inability to culture the animal through the life cycle. Unlike the eggs of most other animals, the eggs of urchins are haploid when spawned. As a consequence, they are easily fertilized and since there is no concern with the timing of meiosis, large numbers of synchronously developing embryos and larvae may be produced regularly. They are as popular a laboratory animal for toxicologic studies as they are for research in cell development. Strict attention to water quality parameters, in particular temperature and salinity, is an absolute necessity with captive urchins.
Urchins are extremely sensitive to sulfide.
Regular tank cleaning must address the issue of H2S build-up. Urchins should be protected from acute sulfide exposure encountered during line changeovers. The ease with which the sea urchin can be maintained and manipulated, coupled with their disease resistance, and an extensive literature generated from their past study make them an attractive alternative to mammalian systems in many aspects of biology. 96 Dogfish sharks have a long biomedical research history at the MBL and at other marine labs as well. Because of their highly evolved and extremely sensitive nervous systems, sharks provide excellent preparations for comparative neuroanatomical studies.