The ancient baobab trees first sprouted on the African savannah about 1,500 years ago, inspiring awe and becoming an icon on the continent. Recognizable for their swollen trunks, one grew so large that a pub was constructed inside, attracting tourists from around the globe. Then, two years ago, the tree began to split apart, and eventually, it completely fell to pieces.
Scientists are now finding that these trees are dying under mysterious circumstances and they are stumped as to why. Several of the oldest and largest African boababs have died over the last decade, according to findings published in the peer-reviewed Nature Plants on Monday.
The researchers say the deaths were not caused by an epidemic since none of the trees show any signs of infection. They do wonder if the deaths might be connected to climate change, but there is no concrete evidence of this.
“We suspect that the demise of monumental baobabs may be associated at least in part with significant modifications of climate conditions that affect southern Africa in particular,” Dr. Adrian Patrut of Babes-Bolyai University in Romania, who led the team, told BBC News. “However, further research is necessary to support or refute this supposition.”
Scientists have been monitoring the baobab trees across southern Africa since 2005. They found that eight of the 13 oldest and five of the six largest trees had either completely died or had their oldest parts collapse. Dry conditions and increasing temperatures might have something to do with the sudden deaths, but the scientists say that more research is needed to know for sure.
“It's shocking and very sad to see them dying,” Patrut said.
The southern African countries where the trees died are warming faster than the global average. Rainfall is expected to continue to decrease as temperatures increase over the next few decades, NPR reported.
It’s not just the baobabs, either. Tropical trees in the Costa Rican cloud forest also seem to be dying from rising temperatures. The rate at which trees are dying is alarming to scientists, who think that the deaths are coming far too rapidly for the trend to be natural.
“It is very likely that human actions, whether by changing the local landscape or altering global climate, have contributed to the death of so many large baobabs,” David Baum, an ecologist at the University of Wisconsin-Madison, told NPR.
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