Life After People is a television documentary series where scientists, structural engineers and other experts speculate with the thought experiment about what the Earth might be like if humanity instantly disappeared, as well as the impact humanity's disappearance might have on the environment and the artificial aspects of civilization. The program premiered as a two-hour special on January 21, 2008 on the History Channel which served as a de facto pilot for the series that premiered April 21, 2009.The program does not speculate on how humanity may disappear, only that it has, and that it has done so suddenly, leaving everything behind including household pets and livestock that have to fend for themselves. The rest of the speculation is based upon documented results of the sudden removal of humans from a geographical area and the possible results that would occur if humanity discontinues its maintenance of buildings and urban infrastructure.