 Before being elected to Congress, he taught an environmental studies class at West Georgia College, and while in office, he was known as one of the most environmentally conscious Republicans.Gingrich co-sponsored the reauthorization of the Endangered Species Act and supported the 1990 Clean Air Act and the Rhinoceros and Tiger Fund.In 2007, Gingrich released the book "A Contract with the Earth", co-written with Terry Maple.