Epidemiologists study outbreaks of diseases, the causes, locations, and how various communities are affected, utilizing relative information to aid in the prevention of future outbreaks. Epidemiologists help to keep the public informed of methods to maintain and improve public health.
Based on these criteria, the smallest known extant shark species appears to be Etmopterus perryi, males of which mature at 16 to 17.5 cm TL and gravid females have been found at 19 to 20 cm TL (Springer & Burgess 1985).
With over 500 species of sharks, there are many different shark sizes and shapes. The largest shark (and also largest fish) is the gentle whale shark (Rhincodon typus), which can reach lengths of 39 feet (12 meters). The smallest is the dwarf lantern shark (Etmopterus perryi) clocking in at only 8 inches long.