This life reconstruction shows what the dinosaur embryo may have looked like in its egg.
One illustration shows a small animal in a tight tuck, legs and a tail are bent towards the tail. This is Baby Yingliang, a nickname created by an ancient dinosaur egg and tucked into a position that looks like that of the modern bird at the time of the hatch.
The baby Yingliang fossil dates to the late Cretaceous in 1876. Its cost between 72 and 66 million years old, and is the remains of a rahettorosaur, and is a very enduring fossil. The preservation of the embryo and the position of the egg make the fossil a significant find.
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The new paper, "that's similar to modern bird embryos," tells the University of Birmingham. Researchers from this institution and Beijing's China University of Geosciences conducted the study, which was published this week in the journal iScience.
The cranial embryo, created by fossilized theropod embryo, shows a dinosaur cleft in his tail before hatching.
Scientists estimate that the dinosaurs would grow around 10,6 inches long (27 centimeters). It is 6.7 inches long and will give you a sense of how much time that creature was folded over.
"The dinosaur embryo and chicken embryo are connected in a similar way," said the researcher. The tucking posture of the bird, which lets the modern bird survive, is a first-generation dread.
The study co-author Steve Brusatte of the University of Edinburgh described the discovery as "one of the most beautiful fossils I have ever seen," adding it is "a more significant remark of the first of the early stages of many dinosaur ancestors"