Key Highlights
- Two bird fossils, dated at roughly 149 million years, were recovered from Fujian Province, China.
- One specimen, Baminornis zhenghensis, possesses a short pygostyle, making it the earliest known short‑tailed bird by almost 20 million years.
- The find challenges the long‑standing view that Archaeopteryx was the sole definitive Jurassic bird.
- A second fragmentary fossil, a wishbone, may belong to the Cretaceous clade Ornithuromorpha.
- Results were published in the journal Nature and led by Prof. Wang Min of the IVPP, Chinese Academy of Sciences.
Detailed Insights
The research team, headed by Professor Wang Min at the Institute of Vertebrate Paleontology and Paleoanthropology, excavated two distinct avian remains from sedimentary layers in Fujian Province. Radiometric dating places these bones in the Late Jurassic, approximately 149 Ma. The more complete specimen, named Baminornis zhenghensis, combines a derived shoulder‑pelvic girdle typical of ornithothoracines with a hand morphology reminiscent of non‑avialan theropods. Its short tail culminates in a pygostyle, a trait previously thought to have emerged only ~129 Ma, thus extending the origin of this feature by nearly twenty million years.
Phylogenetic reconstruction positions Baminornis as a derived member closely allied to Archaeopteryx, yet its mosaic of primitive and advanced characters suggests a broader diversification of birds before the end of the Jurassic. Concurrently, a solitary furcula recovered from the same horizon exhibits shape metrics aligning with Ornithuromorpha, a lineage that later flourished in the Cretaceous. The fragmentary nature of this second fossil precludes formal naming, underscoring the need for additional material to clarify its taxonomic placement.
Collectively, these discoveries fill a conspicuous gap in the avian fossil record, prompting a reassessment of the tempo and pattern of early bird evolution and casting doubt on the exclusivity of Archaeopteryx as the archetypal Jurassic avian.
Key Concepts
- Pygostyle: A fused set of caudal vertebrae forming a short tail tip, characteristic of modern birds.
- Ornithothoracine: A clade of birds possessing advanced shoulder and pelvic structures that facilitate powered flight.
- Phylogenetic analysis: A methodological framework that uses morphological or molecular data to infer evolutionary relationships.
- Ornithuromorpha: A diverse group of early birds that gave rise to most modern avian lineages during the Cretaceous.
- Mosaic evolution: The occurrence of both ancestral and derived traits within a single organism, reflecting incremental evolutionary change.