An international team of geologists and paleontologists is pioneering a groundbreaking methodology to reliably determine the age of fossil-bearing rocks \u2014 by directly dating fossilized dinosaur eggshells.<\/p>\n
The study \u2014 co-authored by Ryan Tucker from Stellenbosch University, Lindsay Zanno from the North Carolina Museum of Natural Sciences and North Carolina State University, and colleagues \u2014 was published in Communications Earth & Environment<\/em>.<\/p>\n Many fossil sites around the world are only coarsely dated. Without precise information on the geologic age of fossils, paleontologists struggle to understand how different species and ecosystems relate across time and space. Usually, researchers rely on dating minerals such as zircon or apatite found associated with fossils, but those minerals aren\u2019t always present. Attempts to date the fossils themselves, such as bones or teeth, have often produced uncertain results.<\/p>\n Tucker\u2019s team took a different approach. They used advanced uranium-lead (U-Pb) dating and elemental mapping to measure trace amounts of uranium and lead housed inside the calcite of fossilized dinosaur eggshells. These isotopes function like a natural clock, enabling scientists to determine when the eggs were buried.<\/p>\n Tests on dinosaur eggs from Utah (USA) and the Gobi Desert (Mongolia) showed that the eggshells record ages with an accuracy of about five percent relative to precise volcanic-ash dates. In Mongolia, the team determined the first-ever direct age \u2014 around 75 million years old \u2014 for a historic locality preserving dinosaur eggs and nests.<\/p>\n \u201cEggshell calcite is remarkably versatile,\u201d says Tucker. \u201cIt gives us a new way to date fossil sites where volcanic layers are missing, a challenge that has limited paleontology for decades.\u201d<\/p>\n By showing that dinosaur eggshells can reliably record the passage of geologic time, the study links biology and Earth science in a new way \u2014 offering researchers a powerful tool to date fossil sites around the globe.<\/p>\n \u201cDirect dating of fossils is a paleontologist\u2019s dream,\u201d says Zanno. \u201cArmed with this new technique, we can unravel mysteries about dinosaur evolution that used to be insurmountable.\u201d<\/p>\n","protected":false},"author":6,"featured_media":114937,"menu_order":0,"template":"","format":"standard","meta":{"_links_to":"","_links_to_target":""},"acf":[],"_links":{"self":[{"href":"https:\/\/naturalsciences.org\/calendar\/wp-json\/wp\/v2\/news\/114936"}],"collection":[{"href":"https:\/\/naturalsciences.org\/calendar\/wp-json\/wp\/v2\/news"}],"about":[{"href":"https:\/\/naturalsciences.org\/calendar\/wp-json\/wp\/v2\/types\/news"}],"author":[{"embeddable":true,"href":"https:\/\/naturalsciences.org\/calendar\/wp-json\/wp\/v2\/users\/6"}],"version-history":[{"count":4,"href":"https:\/\/naturalsciences.org\/calendar\/wp-json\/wp\/v2\/news\/114936\/revisions"}],"predecessor-version":[{"id":115665,"href":"https:\/\/naturalsciences.org\/calendar\/wp-json\/wp\/v2\/news\/114936\/revisions\/115665"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/naturalsciences.org\/calendar\/wp-json\/wp\/v2\/media\/114937"}],"wp:attachment":[{"href":"https:\/\/naturalsciences.org\/calendar\/wp-json\/wp\/v2\/media?parent=114936"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}