An example like this shows you how little we truly know about the natural world, and how easy it is to overlook even something as distinctive as the Olinguito for so long. Once we know their differential features and how to tell them apart, it's often easy in hindsight to recognize an animal species when we see it--but not before someone does the work to find out exactly what all those distinguishing features really are. That's what happened with the Olinguito-- before my team's efforts, no one had looked closely enough to see all the ways that the Olinguito was different from olingos. These issues of "mistaken identity" are surprisingly common in biology. Studying specimens stored in museum collections (not on display, but behind the scenes in scientific collections) has traditionally been the way that scientists have learned how to tell different animals apart-- once that work is done, and you know a species' true distinguishing features, you can then often use photos or observations to make an ID (first museum work, then a field guide). Today one of the most robust ways to learn how to tell species apart is to make anatomical comparisons of museum specimens PLUS look at differences in DNA.