Archaeologists in China have dated dinosaur eggs for the first time, revealing the age of the ancient fossils, according to a new study published in Frontiers in Earth Science.
Researchers Used an ‘Atomic Clock’
A research team, led by Bi Zhao of the Hubei Institute of Geosciences, uncovered the fossils at the Qinglongshan site in the Hubei Province. Utilizing an “unprecedented” technique known as in-situ carbonate uranium-lead (U-Pb), the research team determined the fossilized eggs, which belong to the Placoolithus tumiaolingensis species, to be 85.91 million years old. The U-pb technique, colloquially referred to as an “atomic clock,” works by shooting micro-lasers at small pieces of eggshell samples, which vaporizes the carbonate minerals into aerosols which scientists can then analyze using mass spectrometers to count uranium and lead atoms.
“We fired a micro-laser at eggshell samples, vaporizing carbonate minerals into aerosol. This is analyzed by a mass spectrometer to count uranium and lead atoms,” Zhao explained in the study. “Since uranium decays into lead at a fixed rate, we were able to calculate the age by measuring accumulated lead—it’s like an atomic clock for fossils.” The dating results were remarkably consistent, showing results within 1.74 million years.
Fossils Hold Secrets of Climate Change
Scientists believe the fossils will hold answers regarding climate change in the Late Cretaceous period, when the Earth’s climate cooled at such a significant rate that it led to the extinction of dinosaurs. “Our achievement holds significant implications for research on dinosaur evolution and extinction, as well as environmental changes on Earth during the Late Cretaceous,” Zhao said. “Such findings can transform fossils into compelling narratives about Earth’s history.”
