Georg Baur (1859–1898) was a vertebrate paleontologist and Neo-Lamarckian who studied reptiles of the Galapagos Islands, particularly the Galápagos tortoises, in the 1890s. He is perhaps best known for his subsidence theory of the origin of the Galapagos Islands, where he postulated the islands were the remains of a former landmass, connected to South America via Cocos Island. Prior to his work on the Galapagos Islands, Baur was an assistant to Othniel Charles Marsh at Yale University. Baur undertook an expedition to the Galápagos Islands in 1891, leaving New York on May 1, 1891, arriving in the Galápagos on June 9th, and departing the islands on August 26th for Guayaquil, Panama, and the return to New York. Baur named several subspecies of Galápagos tortoise, including Chelonoidis nigra guentheri (Baur, 1889), and Chelonoidis nigra galapagoensis (Baur, 1889). Not all of Baur's tortoise taxa are still considered valid.