Sorting things into categories is one of the first scientific skills that children can learn. Categorizing, be it socks, rocks or plants, just seems to be an innate human urge. Categories help organize the world around us. Naming those categories allows us a simpler way to identify, compare and talk about them. Classification systems are essential to science; they act as the scaffolding that enables scientists to stand up close and get to know plants, rocks or anything else.
But any classification system, however useful, is ultimately simplistic. No such system perfectly describes reality and the wonderfully messy wonders of nature. And so classification systems get tweaked, revised, renovated or completely replaced to accommodate new discoveries. And, as we have reported before (“The name of the fungus,” SN: 5/3/14, p. 22), and will again (Susan Milius is now at work on a story about the latest thinking on biological classification), scientists spend a good deal of time and energy arguing about such changes.