How is our understanding of the natural world deeply cultural? What is the impact of human activity and technology on this world? In the Ecology episode, artists Robert Adams, Mark Dion, Inigo Manglano-Ovalle and Ursula von Rydingsvard address the submission of wildernes by civilization, the foundations of scientific knowledge and mankind's relationship to the Earth. Art21: Art in the 21st Century is an award-winning series of 24 programmes in which 100 contemporary artists explain their creations, their creative processes, and their perceptions of art. Available for the first time on video in the UK, Art21 covers a wide range of artists and contemporary visual art.