There are three main subclasses of gastropods; the Prosobranchia (ocean snails), Opisthobranchia (sea slugs, sea butterflies and sea hares), and Pulmonata (land and freshwater snails and slugs). Each of the subclasses has evolved in their own way and members differ in their reproduction and life cycles within the subclasses. The gastropod folks are so large it really is impossible to spell out living cycle of each one individual species, but a majority of general rules do apply. The more evolved the species, the more complex their reproductive cycle in addition to their biology. Here we will look at the life span cycle of a gastropod through various examples and how they differ with regards to the type. Traditional adult rheumatology training includes four years of medical school, one year of medical internship, two years of medical inpattern and two years of rheumatism association. The American board of Internal Medicine offers a sub-specialty committee for rheumatology certification that can provide board approval to approved rheumatologists.