A GIANT GALAPAGOS SURPRISE

The Galapagos Islands are famous for their giant tortoises, with at least 11 of the islands each formerly having its very own subspecies – which some authors elevate to species in their own right. Tragically, however, some of them are now extinct after having been killed for their tasty meat in earlier ages or dying out when their habitat was destroyed by introduced species. Consequently, it came as a great surprise recently when scientists revealed that a hitherto unknown subspecies of Galapagos giant tortoise had been hiding in plain sight. It has long been known that the Galapagos island of Santa Cruz has giant tortoises living on its eastern side in a locality called Cerro Fatal, and on its western side in a region known as La Reserva. Yet although the two groups display minor morphological differences from one another, they have traditionally been categorised as one and the same subspecies, Chelonoidis ( nigra) porteri. Following DNA analyses and comparisons of samples taken from eastern and western specimens, however, a scientific team led by Yale University evolutionary research biologist Dr Adalgisa Caccone has now announced that the eastern specimens are sufficiently distinct genetically from their western brethren to require classification as a subspecies in their own right. Indeed, they are actually genetically closer to the giant tortoises on other Galapagos islands than they are to the western Santa Cruz giant tortoises. Consequently, the eastern Santa Cruz giant tortoise has now been formally separated from the latter taxonomically, and has been dubbed C. (n.) donfaustoi in honour of Fausto Llerena Sanchez’s 43 years of work in Galapagos giant tortoise conservation. www.livescience.com/52545-new-speciesgalapagos-tortoise.html 21 Oct 2015.