Off the coast of the Caribbean islands lived three sharks. They were all different colors: Olly was navy, Ellie was a light blue, and the final shark, Dany, was a light grey. The three lived very happily together and got along nicely.
One day, the sharks noticed that there were a lot of sharks in their bay. They were constantly bumping into each other and competing for stray fish from the reefs. At one point, they were fighting with each other for a single, small fish which was extremely unlike them considering they were so compatible with each other.
As the sharks got older, they realized that they were able to find and hunt food the best in various areas of the ocean. Olly hunted best in the deeper ocean, Dany could hunt best in the shallower water, and Ellie could hunt in either area. This was due to their different skin tints.
As time went by, Dany, Olly, and Ellie had children, and their children had children. Those who failed to hunt enough food died, and the rest lived to reproduce. It was not surprising that Ellie's descendants were the majority of the remaining survivors because her skin color enabled her to hunt in shallow and deep water.