Are they, aren’t they?: What it takes to declare a species extinct

It can take years of work, heated debate and anxious enquiry to confirm an extinction. And even then one can run into the potentially deadly Romeo Error.

It’s hard to tell when something isn’t there. And so, extinction lists around the world are places of heated debate, rebuttal, and anxious enquiry. There’s even a pitfall with an endearing name: the Romeo Error.

Let’s get to that one first. The Romeo Error occurs when a species thought to be dead (like Romeo at the end of the Shakespearean play) turns out to be alive (as in the play) and the error of thinking him dead ends up having