sentences: alligators eat frogs / turtles / fish / mice / birds & frogs / turtles / fish / mice / birds are kinds of animals ->  alligators eat animals  alligators eat animals & a predator eats other animals for food ->  alligators are a kind of predator  alligators are a kind of predator & as the population of prey decreases , competition between predators will increase ->  as the population of prey decreases , competition between alligators will increase  an animal is a kind of organism & a species means a group of a certain kind of organism ->  a species means a group of a certain kind of animal  a species means a group of a certain kind of animal & an alligator is a kind of animal ->  an alligator is a kind of species of animal  an alligator is a kind of species of animal & competition may cause animals to act aggressively towards members of their own species ->  competition may cause alligators to act agressively towards members of their own species  as the population of prey decreases , competition between alligators will increase & competition may cause alligators to act agressively towards members of their own species -> as the population of prey decreases , agression between alligators will increase