In the image to the left you see three human males. You can generate three pairings of these individuals. When comparing these pairs which would you presume are more closely related than the other pairs? Now let me give you some more information. The rightmost image is of the president of Tanzania. The middle image is of the president of Taiwan (Republic of China). And finally, the leftmost image is of the prime minister of Papua New Guinea. With this information you should now know with certainty that the prime minister of Papua New Guinea and the president of Taiwan are much more closely related than either are to the president of Tanzania. But some of you may not have guessed that initially. Why? I suspect that physical inspection may have misled you. One of the most salient visible human characteristics is of the complexion of our largest organ, the skin. Its prominence naturally leads many to mistakenly infer relationships where they do not exist.
This was certainly an issue when European explorers encountered the peoples of Melanesia. An older …