#Ecology# ^w^ Every organism has an assigned role in the ecological system of the planet. ^w^ Sharks serve a fitness requirement in the oceans by weeding out the sick and injured. This process of natural selection helps to keep other marine species strong. ^w^ Sharks have their own ecological pressures. Their life history pattern and slow rate of maturity demand that they live in a stable environment. Unlike fish, sharks cannot survive a catastrophe. ^w^ The removal of an apex predator from the oceans could have catastrophic results to the rest of the marine system.