Fact-seals fear sharks. Seems common sense, right? Well as silly as it seems scientists have done entire and likely costly study to determine this to be true. The results … it is true. What was interesting to me about the study though is the way they measured the seals’ fear. In this three-year study, researchers tested the stress levels in seal colonies that have varied exposure to great white sharks hunting them. The cortisol stress hormone glucocorticoid released when they