Early Cretaceous bird track fossil named 'Exquisite Zhucheng Bird Footprint'

The "Exquisite Zhucheng Bird Footprint". [Photo by Zhang Minmin for chinadaily.com.cn]

According to the Zhucheng dinosaur culture research center in Weifang, Shandong province, the fossilized bird footprints from the Early Cretaceous period, dating back over 100 million years, discovered locally, have been officially named "Exquisite Zhucheng Bird Footprints".

"The Cretaceous period was not only an important period for the spread and evolution of vertebrates such as dinosaurs, but also for birds. A large number of early Cretaceous bird footprints have been discovered both domestically and abroad, and these findings hold significant scientific importance in understanding the paleogeography, pale environment, and pale climate of the Cretaceous period," explained Zhang Yanxia, deputy researcher of the Zhucheng dinosaur culture research center.

In 2023, researchers from the Zhucheng dinosaur culture research center and the Shandong Institute of Geological Sciences conducted a detailed study on a set of well-preserved Early Cretaceous bird tracks found at the Zhangzhuhe Bay dinosaur track site in Zhucheng. They found that the footprint characteristics differed from previously discovered bird tracks.

A researcher measures the length of the "Exquisite Zhucheng Bird Footprint". [Photo by Zhang Minmin for chinadaily.com.cn]

The "Exquisite Zhucheng Bird Footprint" is a small, four-toed bird track, measuring 3.1 centimeters in length and 2.9 centimeters in width. The toe marks are slender and shaped like long cones, with a noticeably smaller imprint at the heel, and a lack of webbing marks. The claw marks and toe pad imprints are unclear, with toes II, III, and IV pointing forward, with II slightly longer than IV. The imprint of the hallux is small, reaching backwards, and forms a 180-degree angle with toe III. Research indicates that it was formed alone the shoreline of a shallow lake during a period of drought.

The "Exquisite Zhucheng Bird Track" is the first bird track to be discovered and named in Zhucheng. Its study and naming have resolved a number of identification and species conflicts. 

The footprint provides conclusive evidence of ancient birds in the Cretaceous period in Zhucheng and holds significant importance in the systematic study of paleobiogeography and pale environmental reconstruction. (Edited by Huang Junyao)