Principle #1: Genetic Variation- Turtles have different characteristics that play a role in their survival. Some turtles are born with strong flippers that allow them to get to the water quickly, out of the reach of certain predators. Others, however, have weaker flippers that do not allow them to go very quickly, making them an easy target.
Principle #2: Overproduction and Struggle for Survival- A female turtle can lay over a hundred eggs, but not all will survive. Some turtles can move faster than others to get to safety, and there are many predators that are after the turtles, like birds and even some fish.
Principle #3: Differential Survival and Reproduction- The turtles with stronger flippers can move faster and escape the clutches of a predator. Turtles with strong flippers will make it to the ocean faster and swim faster to avoid predators in the sea. Turtles with stronger flippers will survive to reproduce.
Principle #4: Change in the Gene Pool- Since most of the turtles surviving and reproducing are those with stronger flippers, there would be an increase in this trait. Since the turtles reproducing have this trait, then there will be an increase in strong flippers in the population. There will be a decrease in the population turtles with weaker flippers.