World's Largest Organism 'Pando' Is Made up of 40,000 Trees, Experts Say It May Be Growing Nonstop

Researchers are stunned by the revelation that the beloved Pando could be older than their previous assumption. The latest discoveries regarding Pando indicate that the organism could be between 16,000 and 80,000 years old, Live Science reported. If true, this finding will make Pando the oldest known living organism on Earth. The research detailing this new postulation has been published in the preprint website bioRxiv. It is yet to be peer-reviewed.

Pando is the name given to a massive quaking aspen covering around 100 acres (40 hectares) in Utah, Live Science reported. To this date, Pando has had the honor of being the largest known living organism in the world. The study intends to associate another distinction with its name. 

Researchers in the study collected hundreds of samples from the vast network of quaking aspen (Populus tremuloides), and after analysis concluded that the structure could have started as a solitary seedling long before the end of the last ice age, around 34,000 years ago, Science Alert reported. The study has attracted a lot of attention from the scientific community because its findings confine Pando's age to a certain number when past speculations ranged anywhere from several thousand to millions of years.

The DNA sequence of the samples helped researchers identify the various changes that happened in Pando for 34,000 years, Nature reported. Their efforts provided them with 4,000 genetic variations across samples.

This data was put into a theoretical model to estimate the organism’s evolutionary lineage. The results showcased that Pando's age could have been anywhere around 16,000 and 80,000 years.  "It makes the Roman Empire seem like just a young, recent thing," said study co-author William Ratcliff, an evolutionary biologist at the Georgia Institute of Technology in Atlanta.

Another unique observation made by researchers in the study was regarding the mutation pattern of the organism. They found that the trees that were closer to each other did not share similar genetic patterns, which is not what happens typically.

"You would expect that the trees that are spatially close are also closer genetically," said co-author Rozenn Pineau, a plant evolutionary geneticist at the University of Chicago in Illinois. "But this is not exactly what we find. We found a spatial signal, but that is much weaker than what we expected."

The study also speculates reasons regarding Pando's resilience for so many years, Nature reported. Researchers believe that the organism's triploid nature has led to it having "bigger cells, bigger organisms, better fitness."

Triploidy happens when an organism's cell contains three copies of each chromosome, rather than two. In such cases, reproduction happens through cloning, and not through other means. According to experts, these clones have more durability compared to mixed offspring and hence could have managed to survive for so many ages.

Philippe Reymond, who researches interactions between plants and herbivores at the University of Lausanne in Switzerland looked through the findings and observed that there could be a built-in mechanism within the organism to protect the genome, Nature reported. This mechanism was likely not allowing Pando to accumulate harmful genetic mutations, a suggestion that is "quite interesting for many scientists." Reymond believes that this mechanism should be studied on a cellular level by experts. 

Ratcliff wants more people to focus on Pando's genetic history and analyze its evolution throughout various ages, Nature reported. "I would love to make a call for people to work on these kinds of organisms," he said.