Were our human ancestors ocean-dwelling? In a TED talk on Greg Laden's Blog, writer Elaine Morgan makes the case that human traits like subcutaneous fat, nearly hairless skin, and bipedalism—traits which distinguish us from chimpanzees and other close relatives—evolved during an aquatic stage in human history. ScienceBloggers, however, spare little belief for this Aquatic Ape hypothesis. On Pharyngula, PZ Myers says that there is "no evidence anywhere for such a stage." And Greg Laden points out that while no current hypothesis for human evolution is flawless, this one in particular doesn't float.