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Something sinister is throwing off the silent timekeepers in trunks.

BY DARREN ORF PUBLISHED: APR 09, 2024 7:30 AM EST

• Trees use unseen circadian rhthyms, or genetic oscillations, to keep track of sequestering carbon or when to go dormant.

• A new study by the National Scientific and Technical Research Council says that a warming world can disrupt this biological clock, which can be a big problem for species that are not tolerant to warmer weather.

• Future temperature increases could drastically change the compositions of forests around the worl

Go on a globe-trotting flight and you’ll quickly get acquainted with your circadian rhythm. That grogginess you feel the next morning post-flight? That’s your internal clock completely out of whack. Humans and animals aren’t the only beings that rely on this unseen timekeeping, trees also can track time independent of inputs from their surrounding ecosystem, but a warming world could be confusing this system that trees rely on to sequester carbon — or even survive.

A new study by National Scientific and Technical Research Council (CONICET) in Argentina studied lenga beech saplings of the species Nothofagus pumilio, a deciduous tree native to the Andes. Although capable of surviving in temperatures down to -22 degrees Fahrenheit, the tree isn’t a fan of warmer weather like its close cousin, Nothofagus obliqua. The scientists discovered that at higher temperatures, the oscillations of 24 genes that regulate the lenga beech’s internal clock were altered. The study was published on the preprint server Biorxiv.

Plant survival in a warmer world requires the timely adjustment of biological processes to cyclical changes in the new environment. Circadian oscillators have been proposed to contribute to thermal adaptation and plasticity in plants,” the paper reads. “We revealed that the upper thermal limits for accurate clock function are linked to the species’ thermal niches and contribute to seedling plasticity in natural environments.”

According to New Scientist, when the circadian rhythms were reset, the tree showed continued patterns of “genetic oscillation.” These changes in oscillations and warmer temperatures made the saplings of the cold-loving Andean beech smaller than the warm-loving N. obliqua. While data about the effects of these circadian oscillations is scarce, misaligned temperatures cues have caused other species of trees to go into out-of-season dormancy, the period when a tree prepares for freezing temperatures.

This is particularly bad news for trees like N. pumilio, whose warm-weather aversion could be an issue as global temperatures continue to climb.

“In this context, the investigation of genes responsible for thermal stability of the circadian clock may contribute to the selection of plant genotypes/populations with increased resistance to warming,” the paper reads. “The effect of increasing temperatures on oscillator function may be one factor which constrains the regeneration of the dominant species N. pumilio, potentially jeopardizing the integrity of the ecosystem of the Andean-Patagonian forests.”

It’s obvious that climate change will change our world, but the unseen temporal worlds of the plant kingdom also won’t escape unscathed.