An ocean quahog clam born around 1499 is the oldest individual ever discovered, demonstrating the species' remarkable longevity.
Age Determination
In 2006, a giant ocean quahog (Arctica islandica) was hauled up from the seabed off the coast of Iceland. Similar to counting tree rings to determine the age of trees, the number of growth rings on a clam's shell can be counted to estimate its age. Using this method in 2007, scientists determined the clam to be over 405 years old, making it the longest-lived mollusk ever recorded, according to IFL Science.
Each year, ocean quahogs grow a new layer on their shells during the summer months when the water is warmer and food is more abundant. This means that when the clam's shell is cut open, scientists can count the number of rings to determine its age. However, subsequent radiocarbon dating results revealed the clam to be even older, at exactly 507 years. This suggests it was likely born around 1499 and was nicknamed "Ming" after the Ming Dynasty that ruled China during its early years.
Longevity Secrets
Quahog clams generally live well over 100 years of age, despite being a commercial fishery species. A. islandica's ability to live so long is attributed to its extremely low oxygen consumption. When animals have extremely slow metabolic rates, they tend to live very long lives, according to marine biologist Doris Abele.
Except for nucleic acid oxidation, the level of damage in A. islandica does not increase with age, indicating remarkable cell maintenance. The correlation between nucleic acid oxidation and age has been demonstrated in many other organisms. Unfortunately, the clam that had lived through the European Reformation and Enlightenment died in 2006 after being placed in a freezer by researchers from Bangor University, UK.
Summary
The ocean quahog clam is an extraordinary species that can live for centuries, demonstrating the incredible diversity and adaptability of marine life. Its extremely low metabolic rate and exceptional cell maintenance abilities contribute to its remarkable longevity. Further research on these ancient creatures could provide insights into aging and the potential for extended lifespans in other organisms.