Between 2005 and 2017, the researchers probed and dated "practically all known very large and potentially old" African baobabs - more than 60 individuals in all.
According to a paper published in the Nature Plants journal, the researchers had investigated and dated "practically all known very large and potentially old" baobabs between 2005 and 2017, only to then unexpectedly note that nearly all of the very oldest and largest trees had died during that period.
The oldest tree which suffered the collapse of all its stems was the Panke tree in Zimbabwe‚ estimated to have existed for 2 500 years. And it's no fluke, he adds. In 2011, the oldest known specimen that sprouted about 2450 years ago-died and toppled over. But in 2016, its stems began to crack and collapse, one by one.
Pretty much every baobab tree in Southern Africa is covered in the healed scars of past elephant attacks, which speaks to the trees unbelievable fix ability, said David Baum, a University of Wisconsin botanist who is familiar with the new study and contributed to a recent Biodiversity International publication cataloguing the trees attributes, in an email.
Thats a tragic loss, considering the history and culture attached to these trees - which are also a key food source for people.More news: Eid-El-Fitr: FG declares public holidays
The scientists did not study why the trees died, though they said climate change in the region was a possible cause. Nadia Drake at National Geographic reports that Patrut began studying baobabs in 2000, mainly focusing on Adansonia digitata, a very large species of baobab found primarily in southern Africa.
The scientists said the spate of deaths, described in the journal Nature Plants, might be the result of a changing climate but that research needs to be done to determine that.
Adrian Patrut, a co-author of the study and an academic at the Babes-Bolyai University in Romania, said: "It is definitely shocking and dramatic to experience during our lifetime the demise of so many trees with millennial ages".
The others saw the death of one or several parts.
Baobab trees commonly form multiple stems, and though the walls of these stems, or trunks, can hold large amounts of water, numerous stems are hollow. But on a baobab, new wood grows both on the outside and into the hollows, meaning that a straight line from the center of the tree can pass both forward and backward in time - or even skip decades altogether if they rotted out or were eaten.More news: Trump says North Korea no longer a nuclear threat
"These trees are under pressure by temperature increases and drought", he says.
Patrut said the dead trunks were only 40% water‚ instead of the 75-80% they should have been.
The baobab tree, sometimes called the Tree of Life, has an unforgettable appearance.
Whatever the cause, these mysterious deaths will have a big impact on the southern African landscape.
"The decline and death of so many large baobabs in recent years is so tragic", Baum says.More news: USA extradites former Panama president