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Ursula Goodenough takes a closer look at biology and the study of life.
Sanjayan discusses the field of conservation science and considers the future of the biosphere.
Today's amazing biodiversity all began with a common single-celled ancestor billions of years ago.
Carbon's ability to form chemical bonds is very important to the history of life on Earth and continues to influence our own future.
Walter Alvarez shows how well-preserved limestone layers in the mountains of Italy offer a rare glimpse at Earth history and early forms of life.