Most of us have seen pictures and probably YouTube videos of "tame" animals on the Galapagos Islands, the biological paradise that was Charles Darwin's major source of inspiration.
Darwin observed nature and gradually developed his ideas about the importance of natural selection as a mechanism by which populations of organisms would change evolve genetically across generations, eventually becoming better and better suited to life in their current conditions.
A corollary of Darwin's revolutionary idea was that organisms would also evolve to lose structures, functions, and behaviors they no longer needed when environmental circumstances changed. He noted that island animals often acted tame, and presumed that they had evolved to be so after coming to inhabit islands that lacked most predators.
But more than 150 years later that almost casual observation remained to come under scientific scrutiny. Now, a team of researchers from the University of California, Riverside, Indiana University Purdue University Fort Wayne and George Washington University have published a study showing that island lizards are indeed "tame" as compared with their mainland relatives. The researchers were able to approach island lizards more closely than they could approach mainland lizards.