The early scientific history of Galapagos tortoises

Specimens of Galapagos tortoises (Testudo, now Chelonoidis) obtained by scientific institutions up to and including the voyage of the Beagle (1835) are reviewed, along with the scientific literature of that period. The idea that all giant tortoises (Galapagos and Indian Ocean) were a single species (Testudo indica) was challenged as early as 1817 by Amasa Delano and refuted scientifically by Harlan in 1826, although his publication was widely ignored; some authors continued to use T. indica for Galapagos tortoises at least until 1855. That Galapagos tortoises varied from island to island was reported first by David Porter in 1815, but such differences continued to be in the realm of hearsay until well after the publication of the second edition of Darwin's Journal of researches in 1845. Contrary to what has been written by modern authors, Darwin did not think that tortoises had been introduced to the Galapagos from elsewhere. Also contrary to popular mythology, tortoises did not play an important role in the development of Darwin's evolutionary theories.