Photo: Crocodiles are often described as primitive creatures with the implication that they are somehow less evolved than other species. All species evolve and continue to evolve. Crocodiles are highly evolved, but so well adapted to their environment that there is evolutionary selection against genetic variation. Accordingly the species remains remarkably stable overt time. Maasai Mara, Kenya. June 2012. Photo by K. Lee Lerner. ©LMG. All rights reserved.