Pando, the tree of more than 40 hectares considered one of the oldest and heaviest living beings on Earth

To the unsuspecting visitor, Pando is nothing more than a beautiful forest of a species of aspen called aspen.

But for thousands of years its roots have kept a genetic secret that makes it even more interesting.

Located in an area of ​​43 hectares near Fish Lake, in Utah, United States, some scientists consider it “the largest and heaviest living organism in the world.”

Because?

It turns out that the 47,000 trees that make it up are connected by a root system and are genetically identical.

“All these trees are actually one tree,” the geographer told BBC Mundo Paul Rogers in 2018.

The phenomenon has attracted scientists for decades. And one of the big doubts that existed regarding Pando had to do with its age.

Although it has long been considered one of the oldest living beings on Earth, experts did not know its age with certainty.

Now, that doubt has been dispelled after a team of biologists managed to date it for the first time.

Your conclusion?

The largest tree in the world It is at least 16,000 years old.

How did they manage to discover it?

To study the evolutionary history of Pando, the biologist Rozenn Pineaufrom the Georgia Institute of Technology in Atlanta, and colleagues collected and sequenced more than 500 tree samplesas well as various types of tissues, including leaves, roots and bark.

The goal was to extract genetic data, looking in particular for the somatic mutationswhich are alterations in DNA that occur in an organism’s cells after conception.

According to statements by Pineau collected by the specialized magazine New Scientist, “In the beginning, when Pando germinated from a seed, “all of their cells contained essentially identical DNA.”

“But every time a new cell is created and genetic information is replicated, errors can occur that introduce mutations in DNAhe explained.

According to the study, by observing the genetic signal of these mutations present in different parts of the tree, the researchers were able reconstruct the evolutionary history of Pando and estimate your age.

It is worth remembering that poplar forests can reproduce in two ways: one is when mature trees drop seeds that then germinate and the other is when they release shoots from their roots, from which New trees are born, which are called clones.

Pando is not the only clone forest, but it is the largest. Since experts consider it to be the same organism, they add the weight of all its trees, resulting in a living being that weighs an estimated 13 million tons.

Between 16,000 and 81,000 years

The researchers made three different estimates of the age of this tree, as they were not sure if they had missed some mutations or if some of the mutations they identified were false positives.

Assuming the scientists correctly identified each mutation in the part of the genome they sequenced, the first estimate says that Pando has about 34,000 years old.

If the experts include possible undetected somatic mutations, the second estimate – and the least conservative – suggests that the tree would have one 81,000 years.

And if you consider that only 6% of the mutations the biologists observed are “true positives,” Pando would then have 16,000 years.

Considering all these uncertainties, Rozenn Pineau and her team They calculated that the age of the tree is probably between 16,000 and 81,000 years.

“Although these scenarios give us quite different numbers, they all point to one notable conclusion: Pando is old,” Pineau told New Scientist.

“Even at his youngest estimated age (16,000), This poplar clone has been growing since the last ice age.”he added.

Through his X (Twitter) account, Will Ratcliff, another of the biologists who participated in the research, indicated that “to put Pando’s age in perspective, even according to our most conservative estimate, was alive when humans hunted mammoths.”

“By our earliest estimate, it germinated before our species left Africa,” he added.

The study, meanwhile, indicates that “regardless of the scenario, these estimates highlight Pando’s notable longevity (…), making it one of the oldest living organisms on Earth.”