So famous that artists have gone so far as to record its sounds! Although it is not the tallest tree in the world, it is nevertheless the tallest “grand” : in fact, Pando extends over some 43 hectares in the Fishlake National Forest, in Utah, a western American state. How can a tree “to spread out” in this way, despite the rigidity of its wood?
In fact, this “body” consists of approximately 47,000 trunks connected to the same root system, and whose genetic material is identical… except for a few mutations. So-called mutations “somatic” which, moreover, allowed a team of scientists to estimate its age from DNA samples collected from leaves, roots and bark.
If the results obtained – currently being validated by peers – are confirmed, “Pando” would be at least 16,000 years old. And possibly 80,000 years, taking the high end! He would thus have experienced the last ice age, which took place between 115,000 years and 11,700 years before the present day.
“Initially, when Pando germinated from a seed, its cells contained essentially identical DNA. But each time a new cell is produced [par division cellulaire, NDLR] and genetic information is replicated, errors can occur, introducing mutations.”Rozenn Pineau, first author of the pre-publication study (bioRxiv), explained to New Scientist.
Records in the plant kingdom
Is “Pando” then the oldest tree? Age calculated by Georgia Institute of Technology (GeorgiaTech) researcher and her team “is corroborated by the almost continuous presence of pollen of aspen in lake sediments collected from Fish Lake, near Pando”underline the authors.
However, a royal holly from Tasmania, also made up of clones, perhaps dethrones it with an estimated age of 43,000 years, notes Sciences et Avenir. The prize for the oldest living organism would, however, go to a Posidonia: more than 200,000 years on the clock. It is also among the seagrasses that we find the largest plant in the world, covering more than 20,000 hectares.
Climate change, drought, pest infestations and ungulate browsing are listed by the National Park Service as threats to aspen across the continental United States, although the species is not considered threatened on the “red list” of the International Union for Conservation of Nature (IUCN).
