An exceptionally preserved specimen of the ancient bird Archaeopteryx, reported on May 14 in Nature, provides unprecedented insights into the evolution of flight. As the 14th specimen ever discovered, its remarkable state of preservation allows researchers to examine details of the bird’s anatomy that were previously obscured, such as the structure of its skull, the arrangement of its feathers, and even the soft tissues on its feet and hands. This new find enhances our understanding of Archaeopteryx, which played a critical role in the transition from ground-dwelling dinosaurs to avian species.
Chicago’s Field Museum, which acquired the fossil in 2022, emphasizes its significance. According to vertebrate paleontologist Jingmai O’Connor, this specimen stands out as possibly the best yet discovered for one of the most critical fossil groups in evolutionary history. Fellow paleontologist Daniel Field from the University of Cambridge notes that the findings highlight the extensive evolutionary changes that occurred between Archaeopteryx during the Jurassic period and modern birds in the Cretaceous. This context helps flesh out our understanding of how flight developed in birds, a process still shrouded in mystery.
Dating back about 150 million years, Archaeopteryx has long been regarded as the earliest known bird, primarily due to its feathered skeleton, which suggests it possessed capabilities for flight. Despite the discovery of other feathered dinosaurs over the years, none have surpassed Archaeopteryx in terms of its recognized status. O’Connor mentions that the evolution of flight from feathered land-dwelling dinosaurs is complex, and Archaeopteryx represents a crucial node in this evolutionary tree. The fossil specimen provides context for how birds transitioned from terrestrial to aerial life forms.
The acquisition of the fossil was a significant gamble for the Field Museum, particularly because it was still encased in rock at the time of purchase. Museum President sought confirmation from O’Connor regarding the decision; her confidence lay in the visible wings, which she believed were the most important feature. Following 1,300 hours of intensive fossil preparation to reveal the complete creature, the researchers were astonished by the nearly flawless specimen, which retained much of its original soft tissues and structural integrity.
Among its critical features, Archaeopteryx’s newly revealed feathers are significant, especially the presence of specialized inner feathers known as tertials. O’Connor notes that while scientists had speculated on their existence, they had never been observed in Archaeopteryx until now. The absence of such feathers in non-avian feathered dinosaurs, including close relatives, supports the theory that flight might have evolved multiple times in birds, depending on shared common ancestors.
Further examinations of the fossil indicate that Archaeopteryx had versatile mobility beyond just flight. Its feet displayed scaled characteristics for the first time, suggesting it may have spent most of its time on the ground. This observation aligns with the understanding that while it could fly, it was not an efficient flyer by modern standards. Interestingly, mechanisms in its hand structure imply capability for climbing, reinforcing existing hypotheses about its potential behavior in its habitat. Overall, this exceptional specimen brings forward new avenues for investigating the origins of avian features and the evolutionary narrative leading to present-day birds.