Any time we do something, we build a likelihood in our mind, consciously or sub-consciously, of whether success will be attained based on our abilities, past experiences, etc. Everyone knows that the dinosaurs have long been extinct. Annie Duke wrote in her book, Thinking in Bets, speaking on coelacanths, a fish:
A mass-extinction event (such as a large meteor striking the Earth, a series of volcanic eruptions, or a permanent climate shift) ended the Cretaceous period. That was the end of the dinosaurs, coelacanths, and a lot of other species. In the late 1930’s and independently in the mid-1950’s, however, coelacanths were found alive and well. As species becoming “unextinct” is pretty common.