DINOSAURS. Yes, some dinosaurs had feathers. The question becomes less straightforward when we focus on pterosaurs, that large family of flying reptiles that dominated the skies until the arrival of a meteorite 66 million years ago that caused their extinction.
Indeed, the presence of feathers (more precisely, more primitive proto-feathers) in these winged animals is controversial among paleontologists. Some argue that these pterosaurs had hair. Conversely, a new study published April 20 in the journal Nature presents many feathers and goes even further.
Led by British researchers, he supports the theory that pterosaur feathers were tools for thermoregulation as well as display. With varied and colorful pigmentation, they would have allowed these prehistoric reptiles to walk and communicate like some modern birds.
Feathers or no feathers?
It is almost established that pterosaurs had a fluffy coat made up of hair-like filaments called pycnofibres. The question then becomes whether these structures are true feathers.
In this study, researchers Maria McNamara, Aude Chincotta and colleagues analyzed a partial skull Tupandactyl Emperor, a pterosaur from the Lower Cretaceous of Brazil (approximately 113 million years ago). Then they found two traces of protofeathers, indicating that these animals had them.
In particular, two types of feathers have been observed on its imposing cranial crest; very small, unbranched monofilaments (red in the picture below) and larger branching structures that more closely resemble the feathers of modern birds (in blue in the image below).
The researchers then analyzed the soft tissues of the pterosaur’s cranial crest. To do this, they took twenty-two samples. shown in the photo below.
Because the soft tissues are well preserved, the team was able to study the smallest details of their structure, in particular the organelles that produce color pigments called melanosomes. They then found different types of melanosomes in both feathers and skin.
This is a first since this feature was previously known only to theropod dinosaurs (specifically the family that includes tyrannosaurs) and extant birds.
Taken together, the finds suggest that while these feathers may not have been used for flight, they may have served as a form of visual communication. In this case, their behavior would be close to some current birds.
Indeed, some modern winged animals use their sometimes bright plumage and their impressive appendages to communicate with their relatives, find a partner, etc. This is the case, for example, with the bird of paradise, as shown in this video:
Old history of feathers
Through these discoveries, the potential origin of the appearance of these melanosomes that allowed this pterosaur to have this coloration can be assessed. Thus, the researchers suggest that this genetic feature, which allows these animals to be so colorful, apparently dates back to the ancestors of avemetatarsals, this group is common to dinosaurs, modern birds and pterosaurs.
According to the researchers, its origin probably dates back to the Middle Triassic and Upper Triassic, namely from 247 to 201 million years ago. Thus, the ability to have a bright “plumage” is much older than one might think.
See also HuffPost: This flying reptile is the largest ever discovered in the Jurassic.