The iguanas, which can stretch up to 18.5 inches (47 centimeters) in length, were first discovered by national park rangers in 1986.However, scientists took decades to recognize the pink iguana as a separate species from others on the island."Knowing all the aspects that make their existence vulnerable will allow us to take timely actions, mainly against invasive species and thus avoid interrupting the natural cycles of these fragile ecosystems," Rueda said.The Galapagos Islands, with its unique wildlife, was a key force behind British scientist Charles Darwin's theory of evolution.It is home to a number of species not found anywhere else including giant tortoises, flightless cormorants and several species of iguanas, including the pink iguana."