What are you doing in my swamp? Long legs suggest bird-like dino was a wader

Embargoed until: Publicly released: 2023-09-07 01:00

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Fujianvenator prodigiosus. Credit: Mr. Chuang Zhao / Springer Nature

Chinese scientists have unearthed the fossilised remains of a long-legged early bird-like dinosaur that strutted its stuff around 150 million years ago, which they've named Fujianvenator prodigiosus. It's thought to be the youngest member of a group of dinosaurs called Jurassic avialans, which later evolved into bird-like dinosaurs and modern birds. The team says the critter was the size of a pheasant with a lower leg twice as long as its thigh, which has never been seen in dinosaurs before. Its long legs suggest it was either a high-speed runner or a wader in watery environments, unlike most other known avialans which are thought to have called trees and the sky home, they say. Other fossils found alongside F. prodigiosus included turtles and fish, the researchers add, so the leggy dino may well have been a wader in swamps.

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From: Springer Nature

Leggy 'bird' hints at a swampy past

An early bird-like dinosaur with long legs from the late Jurassic period of China is described in this week’s Nature. The unusual theropod fossil sheds new light on the evolution of birds and the terrestrial ecosystem of the time.

Birds diverged from bipedal dinosaurs during the Jurassic period, but our knowledge of their early evolutionary history is hampered by the paucity of fossils from this time. A new fossil found in China’s Fujian province and estimated to be 148 to 150 million years old may offer new insights. Min Wang and colleagues describe what may be the youngest known member of the Jurassic avialans — the clade that contains modern birds and bird-like dinosaurs. Fujianvenator prodigiosus was a pheasant-sized avialan with a lower leg (tibia) that is twice as long as the thigh (femur), a previously unknown condition for non-avian dinosaurs, suggesting that it was either a high-speed runner or a long-legged wader. This finding contrasts with other early avialans, which are thought to have been more arboreal and aerial in nature.

Fujianvenator was found among a diverse collection of vertebrate fossils dominated by aquatic and semiaquatic species, including turtles and ray-finned fish, which are indicative of a swampy ecosystem. The authors dub this collection the Zhenghe Fauna. This environment, with its diverse array of inhabitants, suggests that the Zhenghe was a site of emerging Jurassic vertebrate fauna around the time when Fujianvenator was present. As such, it fills an important gap in our understanding of Late Jurassic Northeast Asian ecosystems.