Dinosaur eggshells can reveal the age of other fossils

Determining the age of dinosaur fossils has long been a challenging endeavor for paleontologists. While sedimentary rock layers offer a glimpse into the geological past, accurately dating the fossils encased within them has proven to be a complex task. Previous methods such as dating fossilized bones and teeth have yielded inconsistent results due to the alterations caused by the fossilization process and the transformation of sediment into rock. However, a groundbreaking study led by paleontologist Ryan Tucker from Stellenbosch University suggests that dinosaur eggshells may provide a solution to this age-old problem. The research team has developed a novel technique for dating these eggshells, which can indicate the time period when they were originally buried under layers of sand, mud, or other sediments. This innovation holds the potential to date not only the eggshells themselves but also the surrounding fossils found within the same geological strata. "If validated, this approach could significantly broaden the types of continental sedimentary successions that can be accurately dated using radioisotopic methods," Tucker explained in a recent publication in Nature Communications Earth & Environment. Fossil eggshells, which have been laid by vertebrates for hundreds of millions of years, possess a unique microstructure that makes them particularly useful for age determination. The crystalline arrangement of calcium carbonate within these shells captures a history of diagenetic changes—physical and chemical alterations that occur during fossilization. These changes can manifest as water damage or fissures caused by the pressure of overlying sediments, which can be identified to ascertain the age of the fossils embedded nearby. This pioneering research could pave the way for more reliable dating techniques in paleontology, greatly enhancing our understanding of the timeline of life on Earth.