다음 글의 내용과 일치하는 것은? Charles Darwin was about as keen an observer of nature as ever walked the earth, but even he missed the pink iguana of the Galapagos. The rare land iguanas were first seen, in fact, only in 1986, when one was spotted by park rangers on Volcan Wolf on the island of Isabela. Since then, they have been found only on that volcano, which would explain why Darwin missed them, since he didn't explore it. An analysis by the researchers shows that there is significant genetic isolation between the pink iguana and a yellow iguana that also lives on Volcan Wolf. And besides the obvious difference in color, there are differences in morphology between the two reptiles, the researchers say. Their genetic analysis suggests that the pink iguana diverged from the other land iguana lineages about 5.7 million years ago. Since Volcan Wolf formed much more recently, the current distribution of the pink iguanas only on that volcano represents something of a riddle, the researchers report.