Reproduction:

            Viviparus georgianus reproduces sexually via a direct life cycle, and it is viviparous, dioecious, and iteroparous (Thorp and Covich, 1820). Viviparous means that the embryo develops within the mother and without an egg (Browne, 1978). Dioecious refers to organisms that have two separate genders, a male and a female (Hickman et al., 2009). Iteroparous is a term used to describe organisms that undergo multiple reproductions. Viviparus georgianus’s life cycle is direct because the juvenile matures into the adult stage without undergoing metamorphosis (Hickman et. al, 2009).  The juvenile hatches from the parent and matures within a year or two to become a viable, reproducing adult (Hickman et. al, 2009). Such a direct life cycle is uncommon among the gastropods (Browne, 1978).
             
            Viviparus snails have different life cycles to partition out resources more effectively, but all of the cycles have certain similarities. First of all, adult snails combat seasonal challenges by moving closer to shore during the spring, summer, and early fall for better food sources. They move out to deeper water during late fall and winter to prevent freezing. During April and May, the ideal feeding months, males compete for the most females. All snails continue to grow throughout the year but with slower growth during the winter. All life cycles represented with this genus exhibit multiple reproductions and a nine-month gestation period. However some species, like Viviparus geogianus, live 2-3 years, whereas other snails, like Viviparus viviparus, live up to four years. Snails will either mature in one year or develop fully in two years. Another possibility is for snails to develop in three years and then begin to reproduce. (Browne, 1978; Thorp and Covich, 1820)
           
            In addition, the genus Viviparus has adapted different reproductive tactics to increase fecundity. Viviparus young have a 40% greater chance of survival than some other gastropods because their parents produce less offspring and provide greater parental care. Increased juvenile survivorship is vital because the snails endure different seasons that decrease food availability and temperatures, thus reducing population size. Another way Viviparus snails have decreased juvenile mortality is by lengthening the female snail’s life span.  Consequently, females get about 30% larger and can carry more offspring. (Browne, 1978; Thorp and Covich, 1820)