Dave Shutton, an investigative reporter, approaches Bart and Lisa as they're fishing and talks to them. In the middle of their conversation, Bart catches a genetically-mutated fish with three eyes, earning him a spot on the front page of the newspaper.
Sophie discusses how plants and animals need to compete in order to survive and the role that adaptations play in their ability to survive. She explains how several animals and bugs have adapted to become better suited to surviving in city environments.
Jean Grey addresses the United States Senate on the topic of mutants. Senator Kelly is opposed to them and convinces the audience that they are dangerous. He advocates for having mutants register themselves so that the government knows who they are and what they are capable of doing.
Gaia shows the Planeteers a news broadcast stating that the oceans have increasing levels of mercury, cadmium and PCBs and how it can be dangerous. Gaia also explains biological amplification, a process in which small quantities of toxins become larger quantities and can reach lethal doses.
The Planeteers go to a laboratory and spot animals being exposed to radiation. Dr. Rottenberry thinks he is helping the animals to be better adapted to life without the protection of the ozone layer. Linka suggests that humans should replace the things we do that cause ozone depletion, but Dr. Rottenberry says that would require the cooperation of nations all over the world.