Meet the Sinosaurus: Chinese Rockclimbers Discover 'Chicken Paw Prints'
In March 2019, a group of rock climbers discovered a string of large 'chicken paw prints' at the Sharen Bomb Shelter in Chongqing, China. Chongqing Municipal Planning and Natural Resources organized a group of paleontologists who identified the footprints of a theropod dinosaur, the sinosaurus.
A study recently published by the combined efforts of Xing Lida, Associate Professor of the China University of Geosciences in Beijing, Dai Hui, Senior Engineer at the Geological Heritage Protection Research Institute, Chongqing Bureau of Geology and Minerals Exploration, and Wei Guangbiao, Research Fellow of Chongqing Institute of Geology and Mineral Resources dated the footprints to be from 190 million years ago.
The newly reported Kayentapus footprints are from the Lower Jurassic Geleshan site is one of the best-preserved examples of this ichnogenus in the region where other theropod species had dominated during the Early Jurassic period. All Kayentapus generally have large footprints, often called a 'bigfoot' species.
Other Kayentapus species with tridactyl tracks ('chicken paw prints') including the T-rex. Based on the length of the stride and footprint sizes, the scientists predicted that the creatures were large and medium-sized theropods, specifically the Kayentapus hopii.
Dai Hui said that 'Although the footprints of Kayentapus are widely distributed globally, they had not been found in Asia,' until this recent discovery. He also shared that 'China provides some of the best-preserved examples of this ichnogenus in Asia and shows that it can be consistently distinguished from robust Eubrontes. The assemblage is further evidence that the dinosaur track sites of the Lower Jurassic were theropod-dominated in Asia and globally with a consistent diversity of track morphotypes.'
There were 46 total footprints ranging from six to fourteen inches in length. Previously, Kayentapus fossils were found in Yunnan, Sichuan, and Shaanxi provinces.
The dinosaur is believed to be a sinosaurus, meaning lizard in Chinese, and was named by Chung Chien Young who is known as the 'Father of Chinese Vertebrate Paleontology' in 1948. As one of the fiercest and largest carnivores of its time, the dinosaur remained at the top of the food chain, weighing about half a ton and growing to 18 feet long.
It also had two crests at the top of its head but were not used for combat. It is believed that the crests would hold open the abdominal cavity of its prey while feeding.
Dong, studying the dinosaur's feet, concluded that it resembled vultures. As carnivores, they probably adapted to feed on large prey such as prosauropods or long-necks.
Another observation was evidence of dental damage. Remodeling the creature's jaw 'contributes to mounting evidence suggesting theropods were highly resilient to a broad spectrum of traumas and diseases,' concluded paleontologists. This is also the first-ever documented dental pathology found on a dinosaur.
Paleontologist Lida Xing is also hoping that the national park would consider closing the area from rock climbers so that the fossil trackway may be preserved. The team shared that 'We very rarely find tracks like this in China, so it will aid in research and public education.'