The Digester

Dinosaur eggshells could give accurate burial ages for fossils

Feb 23rd 2026

Researchers led by Ryan Tucker at Stellenbosch University describe a method that uses the microstructure of fossil eggshells and uranium-lead dating to determine when those shells were buried, offering a way to date rocks and other fossils in the same sedimentary layer.

  • The team published the method in Nature Communications Earth & Environment led by paleontologist Ryan Tucker.
  • Eggshells preserve a unique calcium carbonate microstructure that records diagenetic changes from fossilization and burial.
  • Applying uranium-lead dating to eggshell material can reveal the time when sediments covering the eggshell were deposited.
  • If validated, the approach could broaden the types of continental sedimentary sequences that can be dated directly by radioisotopes.