It has long been thought that pterosaurs – everyone’s favorite flying reptiles – had the skies to themselves until the late Cretaceous period when they died out and were replaced by birds. It seemed logical since pterosaur fossils were rarely found with early bird fossils. That’s no longer the case and paleontologists are redrawing their pictures of what the prehistoric skies looked like.
Researchers digging on Hornby Island in British Columbia, Canada, found a partial skeleton of a winged creature consisting of an arm bone (humerus), a fused vertebrae (notarium) and what look like pieces of other limbs. According to their report in the journal Royal Society Open Science, it was at first assumed to be a bird since bird fossils have been found on Hornby Island, but the notarium identified it as a small pterosaur with a wingspan of about 1.5 meters, making it a mini-me to its giant cousins with the 11-meter wingspans. The humerus showed signs of maturity so this was definitely a small adult pterosaur – possibly an azhdarchid - and not the baby of a larger one.
The discovery of the small pterosaur has both scientific and political implications. Its existence confirms that smaller pterosaurs out-survived the larger ones and co-existed with birds, rather than going extinct from competing with the more agile warm-blooded creatures. Their bones were so thin and fragile that they’re rarely found, leading to the previous theories on their demise.
The political implications are just as interesting. Paleontologists specializing in smaller dinosaurs feel prejudiced against by museums because their small fossils and fossil fragments are not as glamorous and complete as the larger dinosaur exhibits. This new small pterosaur discovery and others like it may open the museum doors to more small creature exhibits.
In fact, the Hornby Island azhdarchid may soon be joined by an "Allkauren koi" – another new species of pterosaur discovered recently in the Patagonia region of Argentina. As detailed in the study in PeerJ, the fossils included a well-preserved and uncrushed braincase which indicated that this was also a smaller pterosaur.
Whether it’s dinosaurs or humans, the discussion these days always seems to eventually turn to size and politics.