Trees are known for being long-lived, but have you ever wondered about the oldest tree on the planet? The world’s oldest tree is also the largest. It is a quaking aspen grove in Fishlake National Forest in Utah, United States. Pando, meaning “I spread,” consists of around 47,000 genetically identical quaking aspen trees connected via a root system.
This forest, identified as a single living organism, holds genetic secrets that have intrigued scientists worldwide for many years. Each stem is a clone of another and originates from a single seed. While it has long been considered one of the oldest living species on the planet, there were many doubts about its age.
That is why a group of researchers from the Georgia Institute of Technology gathered to discover the age of this tree through a detailed genetic study – to surprising results. According to the lead author and biologist Rozenn Pineau, though Pando’s cells contained identical DNA upon germination, errors occurred over time with the creation of new cells and replication of genetic information, introducing mutations into the DNA. The researchers could reconstruct Pando’s evolutionary history by observing these mutations.
From this study, researchers made three estimates of the tree’s age. If the scientists had correctly identified every mutation in the genome they sequenced, Pando would be about 34,000 years old. If the research team considers possible undetected somatic mutations, the second estimate places the age at 81,000 years. However, if only 6 percent of the mutations observed are considered “true positives,” the tree would be 16,000 years old. The most conservative estimate indicates that Pando would have been alive when humans hunted mammoths. The earliest suggests it germinated before humanity left Africa.
Regardless of which estimate is accurate, this study proves Pando to be one of the oldest living organisms on Earth.