A shark's size has a lot to do with its genetics and environment, experts say. Males typically grow in length faster than females, due to their larger muscles and other internal organs. In addition, their food sources (such as fish) tend to be bigger than those of female sharks, leading to greater growth. Meanwhile, Great White Sharks typically live in colder waters than other sharks, meaning they have to eat more in order to survive. All of these factors together lead to great whites growing sizeable specimens.