See, humans have always tried to categorize animals because, well, we like categorizing. But one man took it to a whole new level: Carl Linnaeus. The Swedish botanist and zoologist had a real penchant for naming things, and single-handedly invented the binomial classification system that we have today. He's why the official name of a platypus isn't 'platypus, but rather "Ornithorhynchus anatinus." Linnaeus and his disciples divided the entire living world into kingdoms, classes, orders, genera, and species. And for a long time, that was great, because mostly wealthy white guys were doing biology and they loved using nomenclature as a gatekeeping tool. To be a well-respected biologist, you had to memorize thousands of Latin names and understand the complicated family trees of every known animal, and the only people who had time to do that were—you guessed it—other rich dudes.