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).
Confidence votes 30. It depends on the type of shark, most sharks like living in warm or tropical waters,such as Hawaii and Australia.Some sharks though can live in colder waters,such as the Greenland shark and the Great White shark.The Great White Shark has even been seen in the cold waters of Sanfransisco.