Groundbreaking investigations spearheaded by paleontologists from the Field Museum of Natural History indicate that Archaeopteryx, recognized as the most ancient bird, possessed a feeding mechanism shaped by the nascent pressures of aerial locomotion. This suggests an intertwined evolutionary trajectory for its diet and aerodynamic capabilities during the formative stages of avian history. The findings are published this week in the journal The Innovation.
A life reconstruction of Archaeopteryx, featuring oral papillae on its palate, a specialized bill-tip organ at its beak’s extremity, and a tongue endowed with enhanced flexibility and sturdiness due to an accessory hyoid bone. Image credit: Ville Sinkkonen.
The act of flight demands considerable exertion. When contrasted with terrestrial or aquatic locomotion, airborne movement represents the most energetically intensive form of transportation, necessitating significant caloric intake.
Consequently, avian species have undergone evolutionary adaptations to excel in both the acquisition and metabolic processing of sustenance.
Approximately 150 million years ago during the Jurassic period, in what is now Germany, lived Archaeopteryx. This creature is identified as the earliest known dinosaur exhibiting avian characteristics.
Dr. Jingmai O’Connor, an associate curator of fossil reptiles at the Field Museum, commented, “For an extended duration, definitive features characterizing the evolutionary leap from terrestrial dinosaurs to flying avian dinosaurs have been notably scarce.”
“These distinctive oral structures observed in Archaeopteryx, also prevalent in extant bird species, furnish us with novel criteria for distinguishing avian fossils from those of non-avian dinosaurs.”
Within this study, Dr. O’Connor and her research collaborators scrutinized the Chicago specimen of Archaeopteryx, which represents the most recent addition to the scientific catalog of this genus.
A comparative analysis was conducted on the spatial arrangement and morphology of the preserved oral tissues in Archaeopteryx with those of oral papillae found in contemporary birds.
Their analysis led to the conclusion that the structures identified were indeed the inaugural instances of Archaeopteryx‘s oral papillae, marking the first such discovery within the fossil record.
Further examination uncovered several other cranial features within Archaeopteryx that had not been previously documented for this species.
A diminutive bone fragment was identified, which was subsequently determined to be a hyoid bone, integral to tongue structure.
While human tongues lack ossification, the majority of bird species possess a set of hyoid bones that constitute the fundamental framework of their tongues.
These skeletal components provide augmented sites for muscular attachment, thereby facilitating the development of highly flexible tongues that aid birds in reaching and manipulating food items.
“This minuscule bone, among the smallest in the body, strongly indicates that Archaeopteryx possessed a remarkably agile tongue, analogous to that of many modern avian species,” stated Dr. O’Connor.
Utilizing CT scanning technology, the research team also detected minute tubular structures within the distal portion of Archaeopteryx‘s beak, indicative of nerve pathways.
Numerous extant bird species exhibit a structure known as a bill-tip organ, an exquisitely sensitive area at the beak’s apex that assists in foraging by probing the substrate.
Collectively, the evidence of oral papillae, hyoid bones, and bill-tip organs in Archaeopteryx points towards the evolution of multifaceted strategies in early birds designed to enhance the efficiency of food acquisition and ingestion. These adaptations are intrinsically linked to their emerging capacity for flight.
“These findings illustrate a pronounced shift in dinosaurian feeding strategies concurrent with the development of flight and the necessity to satisfy the substantial energetic demands associated with aerial locomotion,” Dr. O’Connor elaborated.
“Birds exhibit a highly efficient digestive apparatus; their entire physiology is optimized for maximizing feeding efficacy and caloric extraction from ingested matter. This sophisticated system commences with the oral cavity.”
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Jingmai K. O’Connor et al. 2026. Avian features of Archaeopteryx feeding apparatus reflect elevated demands of flight. The Innovation 7 (2): 101086; doi: 10.1016/j.xinn.2025.101086
