New Galapagos Islands Tortoise Species Discovered

In the Galapagos Islands, researchers have discovered a new species of giant tortoise that is distinctly different from the other tortoises on the island. This particular species, called Chelonoidis donfaustoi, is found on an arid part of Santa Cruz island; about 250 of these tortoises are said to be located there. This discovery confirms a long-held suspicion among some researchers that an inland subset of tortoises located away from the main population is, in fact, a wholly different species.

The Chelonoidis donfaustoi tortoises are located about 20 kilometers away from the main population on the island. U.S. Geological Survey wildlife biologist Tom Fritts first suggested the two groups may be different species, citing the physical distance between the two as the main source of his suspicion.

This suspicion led to a team of researchers investigating the two tortoise collectives; they examined a dozen microsatellite loci regions of nuclear DNA, among other things, and ultimately found a total of 25 mutations between the two groups. Such a difference confirmed that they were two separate species, something that otherwise wasn't readily discernible by looking at the groups.

In an effort to learn about their origins, the team also used data from over the past two decades to assemble a family tree of sorts for the tortoises on the island. As it turns out, this newest species' closest relative lives on the island San Cristobal, not Santa Cruz.

SOURCE: Nature