Author: Richard Cloutier, Professor of Evolutionary Biology, Université du Québec à Rimouski (UQAR)

What do the ginkgo (a tree), the nautilus (a mollusc) and the coelacanth (a fish) all have in common? They don’t look alike, and they aren’t biologically related, but part of their evolutionary history bears a striking resemblance: these organisms are referred to as “living fossils”. In other words, they appear to have escaped the transformations that normally come about over time, through evolution. For the past 85 years, the coelacanth has been dubbed a “living fossil” because it evokes a bygone era, the age of dinosaurs. These fish belong to the sarcopterygians, a group that also includes lungfish (fish…