So what happens to the world when the human population begins to outgrow the planet? What will happen to the rest of the species on earth? How long before the resources run out? These questions and more are addressed in the new book, "Countdown: Our Last, Best Hope for a Future on Earth?"
Bestselling author Alan Weisman visited the University of Arizona to talk about his long-awaited follow up to the popular "The World Without Us."
Listen to Robert Alcaraz's interview with Alan Weisman below and some additional material from Weisman's experiences when he traveled to 21 countries while researching for Countdown.
Alan Weisman recounts a story about a man from Thailand in his new book, “Countdown: Our Last, Best Hope For A Future On Earth?” Weisman talks about how the Thai man was able to inform his country about contraception.