March 5, 1938-Nov. 22 , 2011 American biologist and University of Massachusetts Amherst Professor best known for her theory on the origin of eukaryotic organelles, and her contributions to the Endosymbiotic theory, which is now generally accepted for how certain organelles were formed. Also associated with Gaia hypothesis- all organisms and their inorganic surroundings on Earth are closely integrated to form a single and self-regulating complex system, maintaining the conditions for life on the planet. http://en.wikipedia.org/wiki/File:Lynn_Margulis.jpg Campbell & Reese AP Biology