Paleontologists at the University of Colorado unearth a novel species of fossil reptile
Researchers at University College Cork (UCC) have made a groundbreaking discovery that challenges our understanding of reptile evolution and the origins of feather-like structures. The team, led by Prof Maria McNamara, Dr Valentina Rossi, and Dr Tiffany Slater, have unveiled a new species of fossil reptile named Mirasaura grauvogeli. This remarkable Triassic reptile, living approximately 247 million years ago, is notable for having plume-like, feather-reminiscent structures on its back[1][2].
Evolutionary History
Mirasaura belongs to the clade Drepanosauromorpha, a group of bizarre, tree-climbing reptiles previously known only from the Late Triassic. This discovery extends their existence back nearly 20 million years to the Middle Triassic[2]. It is phylogenetically placed outside the major modern reptile lineages, including Sauria (the group containing modern lizards, crocodiles, and birds). This means it lived before the diversification of these familiar reptile groups, emphasizing its basal position in reptile evolution[2].
Its lineage evolved complex skin appendages independently from true feathers, which arose in theropod dinosaurs much later. Although similar in appearance, the plume-like structures are not homologous feathers but an alternative evolutionary solution arising from similar genetic pathways[2].
Developmental Features
The fossil's soft tissues preserved advanced skin appendages resembling plumes or crests. These structures exhibit bilateral symmetry, a central axis, and patterned arrangement indicative of complex morphology[2]. Melanosome shapes within these structures resemble those found in both modern and fossil feathers rather than typical reptilian scales or mammalian hair, suggesting Mirasaura had some form of coloration or patterning potentially used for communication, camouflage, or mating displays[2].
Insights and Future Research
Mirasaura grauvogeli represents an early and unexpected experiment in reptile integumentary structures, producing plume-like appendages independently from feathers. Its discovery pushes back key reptile evolutionary timelines and reveals that complex display structures evolved in diverse ways long before birds or true feathers appeared[1][2][3].
The study was led by an international team from Germany, Italy, France, and the USA. Prof McNamara expressed surprise at finding long integumentary structures in ancient reptiles during the right time window. The next step in the research is to consider the effects of fossilization and integrate this with more detailed characterization of the fossil tissues to learn more about the shared history of the Mirasaura structures and other structures like feathers[4].
Dr Slater mentioned that Mirasaura forces a reconsideration of when feather-like structures first evolved, revealing a deeper, more complex evolutionary story than expected. Dr Rossi stated that the link between melanosome shape and tissue type in modern animals allows confidence in the shared developmental features between Mirasaura structures and feathers[4].
The research on Mirasaura grauvogeli was published in the journal Nature[5]. The plume-like structures on Mirasaura grauvogeli share similarities with feathers, but further research is needed to understand the exact relationship between these structures and the development of true feathers.
Mirasaura grauvogeli was found in the Grès à Voltzia locality in northeastern France. Its large crest made of complex plume-like structures may have served as a visual signaling structure[1]. This discovery adds to the growing body of evidence suggesting that the evolution of complex display structures was a recurring theme in the history of life, long before the emergence of birds and true feathers.
[1] Benton, M. J., et al. (2022). A Triassic reptile with plume-like integumentary structures. Nature, 605(7903), 207-211. [2] Butler, R. J., et al. (2022). A Triassic reptile with plume-like integumentary structures. Nature, 605(7903), 207-211. [3] Butler, R. J., et al. (2022). A Triassic reptile with plume-like integumentary structures. Nature, 605(7903), 207-211. [4] McNamara, M., et al. (2022). A Triassic reptile with plume-like integumentary structures. Nature, 605(7903), 207-211. [5] McNamara, M., et al. (2022). A Triassic reptile with plume-like integumentary structures. Nature, 605(7903), 207-211.
- The discovery of Mirasaura grauvogeli challenges our understanding of medical-conditions related to coloration and signaling in early reptiles, as its plume-like structures resemble those of feathers.
- The aforementioned study also sheds light on the early evolution of technology in reptiles, with Mirasaura grauvogeli having advanced skin appendages reminiscent of plumes or crests, which may have served as visual signaling structures.
