University of Georgia researchers develop shark age estimation tool

Researchers at the University of Georgia have developed a new method to estimate the age of sharks by analyzing DNA methylation, a process known as an epigenetic clock. Published in the journal ‘Molecular Ecology’, the study marks the first successful application of this technology in sharks.

Traditionally, determining a shark's age required analyzing growth bands in vertebrae, a method that is often invasive and requires the animal to be killed. The new approach uses blood samples to identify chemical changes in the DNA that occur predictably as an organism ages. In tests conducted on zebra sharks (Stegostoma tigrinum) at facilities including the Georgia Aquarium, researchers were able to estimate chronological age with a median error of only one to two years using just 10 specific DNA markers.

This non-invasive tool is expected to assist conservation biologists in understanding the age structure of wild shark populations and the life cycles of other marine creatures, providing critical data for marine population management.