A technician climbing a long pole above a forest
A technician climbs a tower to locate lightning strikes in the study area on Panama's Barro Colorado Island.
Getting struck by lightning might not sound like a very wise idea to us, but for one tropical tree species, an occasional zap is a good thing. The almendro trees found in Panama’s forests can get a boost from this electrical jolt and have perhaps even evolved to act like lightning rods, according to a new study published last week in the journal New Phytologist.
Evan Gora, a forest ecologist at the Cary Institute of Ecosystem Studies, became interested in the impact of lightning on the trees after noticing they seemed to survive being hit—and sustained little damage. “Seeing that there are trees that get struck by lightning and they’re fine was just mind-blowing,” Gora recalls in a statement.
So, Gora and his colleagues tracked 93 trees that were struck by lightning at the Smithsonian Tropical Research Institute on Barro Colorado Island in Panama. They used a system of lightning strike-locating instruments to pinpoint which trees had likely been hit by bolts. Between 2014 and 2019, the researchers would check in on the trees to assess their condition, two to six years after the strike. Nine of the trees were from the almendro species (Dipteryx oleifera)—and they all seemed to be doing much better than their lightning-struck peers.
YouTube Logo
Within two years of being hit, 64 percent of the other trees died. Meanwhile, the almendro trees thrived. They gained space as the electricity traveled through their branches, their leaves or the air into nearby trees, killing them. In fact, the study found that trees living near a large almendro tree are 48 percent more likely to be killed by lightning than those living near another species. “Any tree that gets close essentially gets electrocuted,” says Gora to Erik Stokstad at Science.
Lightning strikes also reduced the number of parasitic vines, called lianas, on the almendros by 78 percent. These vines would ordinarily grow on top of the tree and steal light from its leaves, but they died back after lightning. Without these benefits, Gora says to Gennaro Tomma at Scientific American, the almendro trees “would not live as long.”
All of this, the researchers suggest, points to the trees having adapted to attract lightning. The trees’ unusual height—they can grow roughly 165 feet tall—and wide crown make them up to 68 percent more likely to be struck by lightning relative to other similar trees, according to the paper.
A view of a forest canopy from above
The almendro tree's fruits and the almond-flavored seeds within them are a crucial food source for animals.
Almendro trees are considered a keystone species in Central America’s tropical forests. Their fruit supports more than 100 animal species during the area’s dry season. Some of the trees’ electrical resistance might come from moisture in their wood.
The new study challenges our idea of lightning as simply a force of destruction. “It’s a really creative piece of work that changes our perspective of how we think about lightning as an agent of disturbance,” Tommaso Jucker, a forest ecologist at the University of Bristol in England who was not involved with the research, says to Science.
“The findings of the study are quite novel and make a significant contribution to our knowledge of plant evolution,” says Allan Carroll, an ecologist at the University of British Columbia in Canada who was not involved in the research, to Scientific American.