Slow steps towards giant discovery - 30th May 2022

Researchers comparing the genetic material of giant tortoises have identified a new species on San Cristobal in the Galapagos Islands. The animals living on San Cristobal, the fifth largest island of the Galapagos, had been misclassified from the bones and shells collected in 1906 from a cave in the island's highlands.

The 20th century explorers never ventured into the northeastern lowlands of the island where this particular group of tortoises lives today, and as a result, this species had been classified as the wrong species.

The researchers, based in the UK and US at the University of Newcastle and Yale University, found that the DNA samples from museums did not match the tortoises living on the island now.

Volcanic islands located in the Pacific Ocean about 1,000 kilometres due west of Ecuador, the Galapagos is a UNESCO World Heritage site, home to unique species of flora and fauna. The archipelago was made famous by British geologist and naturalist Charles Darwin and his observations on evolution. His studies inspired his theory of evolution, which has become a cornerstone of modern understandings of how life develops. The Galapagos is renowned for its giant tortoises, some of which are over 100 years old.

Ecuador's environment minister, Gustavo Manrique Miranda, has praised the efforts of the researchers. He said, "Good news! Genetic studies carried out by the University of Newcastle, Yale, the Galapagos Conservancy and other institutions revealed that San Cristobal Island in the Galapagos is home to a species of giant tortoise not yet described by science."

Seeking to identify whether San Cristobal's current tortoise population needs to be given a new name, researchers will attempt to retrieve further DNA samples from bones and shells in museums, in a bid to understand the relationship between the two species.