Africa's oldest baobab trees are dying at an unprecedented rate, and climate change may be to blame

Doyle Rice | USA TODAY

Baobab trees — an icon of the African continent and the heart of many traditional African remedies and folklore — are dying across the continent, and scientists are trying to understand why.

A study published Monday found eight of the 13 oldest trees in Africa have died over the past decade, and the authors suggest climate change may affect the ability of the baobab to survive.

"The deaths of the majority of the oldest and largest African baobabs over the past 12 years is an event of an unprecedented magnitude," the study authors said. "These deaths were not caused by an epidemic, and there has also been a rapid increase in the apparently natural deaths of many other mature baobabs."

Baobabs — also known as "dead-rat" trees after the shape of their fruit — are among the most distinctive plants in the world, featuring stout, massive, branchless trunks that can look like pillars.

The study's lead author, Adrian Patrut, a chemist at Romania's Babeș-Bolyai University, told NPR that "such a disastrous decline is very unexpected. It's a strange feeling, because these are trees which may live for 2,000 years or more, and we see that they're dying one after another during our lifetime. It's statistically very unlikely."

Using radiocarbon dating, the researchers analyzed more than 60 of the largest and potentially oldest baobab trees in Africa from 2005 to 2017. They were surprised that most of the oldest and biggest died within those 12 years.

Overall, five of the six largest baobabs either died or their oldest parts significantly deteriorated.

Man-made climate change is a likely suspect, scientists said. Increased temperature and drought are the primary threats, Patrut told BBC News. Researchers said further research is necessary to support or refute that idea.

Thomas Lovejoy, an environmental scientist at George Mason University, who was not involved in the study, told The Washington Post that "something obviously is going on in almost selectively affecting the largest and oldest. I do think climate is a likely culprit, but they don’t actually present any evidence of how climate is changing where these ancient trees occur.”

Whatever the cause, these mysterious deaths will have a big impact on the southern African landscape. In addition to shade, the tree’s bark, roots, seeds and fruit are food sources for many animals, according to Science magazine.

The study was published in the peer-reviewed British journal Nature Plants.