Chickens have been given unusual attention this week, let’s talk about dinosaurs. Today’s birds, of course, are descendants of the only branch of the dino tree that made it through the end-Cretaceous mass extinction. In the Helsion days of dinosaurs, early birds were a little different, although they retain teeth and foreclaves amid some subtle anatomical differences with their modern lineage. The new fossil discovery reveals the unpredictable bird of the time – with a big-big, touch-like beak.
Fossilized, named Falkatkeli Forster, Comes from the Cretaceous rocks at the end of Madagascar. Many of the fossils of early birds we have found so far have come from the Early-Cretaceous rocks in China, a further question mark over that period and on the end-Cretaceous extinction. The new fossil is a nicely preserved head of a crow-sized bird with a sharp, long, tall and narrow beak.
Early Chinese birds did not show much variation in the shape of the fossil beak. This is a big contrast with modern birds, which have wild different beak shapes to suit a variety of ecological structures. Pelicans, woodpeckers, and parrots have very different diets that require job-friendly beaks. It was assumed that an extended beak would not be possible until some anatomy had migrated to parts of the skull, meaning that early birds were only limited. But new discoveries show that were not entirely true. The species could have inhabited an ecological structure that was empty after extinction – until a more modern bird later entered it.
The researchers used 3D imaging to accurately determine the parameters of each anatomical component. It showed some differences compared to both non-bird theropod dinosaurs or more modern birds. The fossil critic may end up with an overall beak shape like some modern birds, but despite the fact that the underlying structure is different.
Near the top of the beak are a few posterior teeth resembling those of its relatives. And the height of its upper beak is achieved by a much larger maxillary bone (brown in the image above), where other fossil species of this time have a thinner, more V-shaped bone. Modern birds, on the other hand, have smaller maxillary bones and beaks, supported by larger premaxillary bones (green near the top of the beak in the image above).
If there is one odd ball l Cretaceous Bird, there may be others, which adds variety to the Cretaceous collection. This also raises interesting questions about the formation of the skull above the skull and the evolution of the beak shape, although modern anatomy clearly did not require a large beak of that shape. It takes a simple story and complicates it somewhat, seeing that the same form has evolved at different times and in different ways.
And that’s good. Surprising relics are even more pleasurable than surprise ones, enriching the picture of our past.
Nature, 2020. DOI: 10.1038 / s41586-020-2945-x (about DOI).
