Irish scientists led a remarkable study that showed that some flying dinosaurs, called pterosaurs, could change and adapt the color of their feathers.
The discovery will effectively rewrite the understanding of pterosaurs — the light-bones flying dinosaurs believed to be the ancestors of modern birds.
UCC scientists Prof. dr. Mary McNamara and Dr. Aude Cincotta worked with Dr. Pascal Godefroit of the Royal Belgian Institute of Natural Sciences, together with other experts in Belgium and Brazil on the revolutionary study.
The two Irish paleontologists, whose research has been published in the prestigious journal Naturecame to their conclusions after exhaustive study of a 115-million-year-old fossilized pterosaur head crest, Tupandactylus imperator†
Named after Tupi, the Brazilian god of thunder, the ancient flying dinosaur lived during the early Cretaceous Period, and details about it emerged after four significant specimens were found in South America in recent years. Adult pterosaurs got a wingspan of more than four meters – and while it was a capable flier, it spent most of its time on the ground looking for food.
The fossil was unearthed in northeastern Brazil, where the pterosaur lived between 230 and 66 million years ago.
Experts had known for years that the particular species of pterosaur was known for its bizarre, oversized head crest.
However, the team found that along the lower edge of the main crest was a fuzzy line of feathers with short, wiry hair-like feathers and downy bifurcated feathers.
“We weren’t expecting this at all,” said Dr. Cincotta. “For decades, paleontologists have debated whether pterosaurs had feathers. The feathers in our specimen close that debate, because they are very distinctly branched along their entire length, just like birds today.”
The big breakthrough came when scientists decided to study the feathers more closely. Using powerful electron microscopes, they were shocked to discover the traces of preserved melanosomes – grains of the pigment melanin.
Unexpectedly, the study found that the melanosomes in different feather types had different shapes.
“In birds, feather color is strongly linked to melanosome shape,” explains Prof. McNamara.
“Since the pterosaur feathers had different melanosome shapes, these animals must have had the genetic machinery to control the colors of their feathers.
“This property is essential for color patterns and shows that coloration was a crucial feature of even the very first feathers.”
The discovery that these pterosaurs had the ability to control the color of their feathers further deepens their similarities to modern birds.
Such an ability to change color can have multiple uses, from breeding, through the ability to attract a mate through display, to other factors such as environment and hunting.
The discovery adds even more weight to the belief that dinosaurs didn’t become extinct, but that a branch of dinosaurs evolved into modern birds.
The remarkable specimen has since been repatriated to Brazil, where it is expected to be the centerpiece of a major paleontological exhibit covering a critical period of dinosaur evolution.
“It is so important that scientifically important fossils such as these are returned to their countries of origin and kept safe for posterity,” said Dr. Godfrey.
“These fossils could then be made available to scientists for further research and could inspire future generations of scientists through public exhibits that celebrate our natural heritage.”
Further research is now underway into the precise nature of the pterosaur’s head, amid claims by other researchers that it could have been an evolutionary development where the animal may have had the best parts of bats and modern birds.
Others have argued that the giant head crest was more for display than for flight or sensory purposes.