For the first time in nearly 150 years, giant tortoises are back on Galapagos' Floreana Island, guided home by NASA data.

The tortoises were bred in captivity and later released on the island.

Add Yahoo as a preferred source to see more of our stories on Google. Sending Galapagos tortoises, including Gramma, to zoos across the United States was part of early efforts to preserve the species ...