Rats can get depressed. Some pigs are extroverted and others are introverted. A conversation with two scientists who say animals have rich inner lives. Then, 100 ways to reverse global warming, ranked in order. Some are unconventional and others can be achieved in your backyard. Plus, Denver walks the line between a fearful immigrant community and federal immigration law. The debate over Denver as a sanctuary city. Also, a professional drone pilot who says racing makes him feel like superman.