Fossils of egg thief hatching 70 million years ago found in my country are consistent with modern birds' hatching posture

  Xinhua News Agency, Kunming, January 3 (Reporter Yue Ranran) After studying a group of dinosaur fossils unearthed in Ganzhou, Jiangxi Province, Chinese paleontologists discovered that this is a rare egg thief in the world that simultaneously preserves adults, embryos and egg nests. fossil.

  This group of fossils was discovered in the stratum about 70 million years ago.

The adult individual egg-stealing dragon is about 2 meters long, with its front limbs splayed backwards and covering the egg nest, and its hind limbs are folded under the body. The whole body is located in the center of the egg nest, which is consistent with the hatching attitude of modern birds.

There are 24 eggs in the nest, arranged in three upper and lower rings.

  Bi Shundong, the first author of the paper and a professor at the Institute of Paleontology of Yunnan University, said: "In addition to the incubation posture of the egg-thief dragon lying on the egg nest, the fossil also contains the embryo that is incubating. This provides the latest evidence for the understanding of egg-stealing dragons’ hatching behavior and hatching methods."

  Egg thirsty is a theropod dinosaur, living between 125 million and 66 million years ago.

In the past, researchers have discovered egg thief individuals lying on egg nests in Mongolia and the Gobi region of Inner Mongolia. However, the lack of embryo fossils in the nest has made the hypothesis of egg thief hatching behaviors controversial for a long time.

  "The egg thief dragon already has'asynchronous hatching', which is a more advanced hatching method among living birds. It can be said that the reproductive method of dinosaurs is far more complicated than previously known." Corresponding author of the paper, Vertebrate Paleontology of the Chinese Academy of Sciences Said with Xu Xing, a researcher at the Institute of Paleoanthropology.

  The results have been published online recently in the international journal "Science Bulletin", jointly completed by Yunnan University, the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences and other units.