Geoscientist and author Marcia Bjornerud talks about her new book "Turning to Stone," which reveals how rocks shape our lives and sustain the planet. From aquifers that purify drinking water to basalt that regulates climate, she shows how rocks are the hidden infrastructure of Earth. Then, biologist and author Karen Lloyd shares a firsthand account of the hunt for life beneath Earth’s surface in her newest book, "Intraterrestrials: Discovering the Strangest Life on Earth."