Isabela Island is almost one hundred nautical miles long from north to south. It has five main shield volcanoes and all of them are considered to be very active—for my own experience, I have witnessed at least a dozen volcanic eruptions in almost every one of them. Something very remarkable about this island is that each active volcano has its own population of giant tortoises, each with a different carapace shape. Just another example of adaptive radiation in Galapagos.