Did NASA really spend millions creating a pen that would write in space? Is chocolate poisonous to dogs? Does stress cause gray hair? These questions are just a sample of the urban lore investigated in this eBook, Fact or Fiction: Science Tackles 58 Popular Myths. Drawing from Scientific American’s “Fact or Fiction” and “Strange But True” columns, we’ve selected 58 of the most surprising, fascinating, useful and just plain wacky topics confronted by our writers over the years. Each brief article uncovers the truth behind everyday mythology, starting with Section One, “In the Animal Kingdom,” where we examine some of the more outlandish claims about our fellow earthly inhabitants, such as whether elephants really remember everything and whether a cockroach can live without its head. Other sections cover reproduction, the environment, technology and personal and mental health. While the answers to some questions, such as whether toilets really do flush in the opposite direction south of the Equator, may only serve to raise your Trivial Pursuit knowledge, others, such as whether to pee on a jellyfish sting or wake a sleepwalker, may come in handy. Although this eBook represents a fraction of circulating folk wisdom and urban mythology, we hope that it’s an enjoyable fraction and that it encourages you to do some debunking yourself.