Please note: This is a companion version & not the original book. Sample Book Insights: #1 The first eukaryotic organism, a single-celled protist, began making sex cells, or gametes, around one to two billion years ago. These were haploid cells that only carried half of the genetic code of the original organism. They needed to combine with other haploid cells to create a fully functional set of chromosomes. #2 The first known example of sex as we know it is from about 385 million years ago, when fossilized remains of the armored fish Microbrachius dicki were found to show the earliest known example of internal fertilization and copulation. #3 The question of why we have sex is still unanswered. Sex creates genetic diversity, but it also risks the best genes being left in the dust while chromosomes that leave you vulnerable to disease and other pitfalls propagate. #4 The Red Queen hypothesis states that life on earth is so competitive that organisms need to keep their feet on the gas pedal of evolution just to have a shot. In other words, defaulting to asexual reproduction might mean your species misses out on a genetic opportunity that could otherwise keep it alive in the face of an unknowable future threat.