premise: fins are a part of aquatic animals used for moving through water sent2: the more water an animal's fin pushes against, the faster that animal will move through water sent3: if an organism 's prey moves quickly then that organism may need to move quickly to catch its prey sent4: eating prey requires catching prey sent5: a something becomes larger it is able to act upon more of something else sent6: fins move animals through water by pushing against water sent7: a predator is a kind of organism.
hypothesis: large fins can be used to move quickly through water in order to catch prey