In the 300,000 years that Homo sapiens has existed as a distinctive species, we have done very well. During this time we have outlived at least five other hominids, including Homo neanderthalensis, which became extinct a mere 40,000 years ago—depending on ancestry, we actually carry traces of Neanderthal genes as a result of interbreeding. We have also managed to populate the entire planet, an accomplishment that has puzzled those who have tried to explain our unprecedented success. Luck was obviously a factor. But an another is now emerging from the genomic analysis of a rare disorder known as Williams Syndrome. (see “The Last Human” by Kate Ravilious, NewScientist, 29 Nov. 2021.)