The extinction crisis: why words matter

A prevalent commonplace in conservation rhetoric is extinction, a word whose meaning is at once intuitive and slippery, the latter because it often is modified as if it were something other than an absolute. The International Union for Conservation of Nature (IUCN) defines extinction clearly enough: It applies only to those species for which there is “no reasonable doubt that the last individual has died.” A child knows that the great dinosaurs are extinct and uses the term in its proper, IUCN sense. How, then, has the word become so freighted with sly and subtle shading in much of the conservation biology literature? Why has this absolute been modified so often – “locally extinct” or “regionally extinct” or “truly extinct,” to name but a few real-life examples – as to become the “very unique” or “more perfect” of the biological sciences?