Some plants have a genetic superpower that may help them survive a cataclysm

"Most people are diploid. That is, we have two sets of chromosomes one set from each parent. But that's not always the case for other species, especially plants. "Strawberries, for example, have eight sets of chromosomes," says Yves Van de Peer, a plant biologist at Ghent University in Belgium. This phenomenon, called polyploidy, happens when an organism has more than two sets of chromosomes stuffed into every cell in other words, a whole genome duplication."

"And it appears to allow some plant species to survive episodes of extreme environmental stress, like changes in the climate. It wasn't obvious to biologists that polyploidy would necessarily be a good thing. In fact, having double the chromosomes can ultimately impact a species' survival, leading to its extinction. And yet, it's pretty common today, especially in plants. This forms what Van de Peer calls the polyploidy paradox."

"When they looked back at ancient genome duplication events in several hundred plant species, they found that they occurred during periods of turmoil over the last 150 million years times of dramatic cooling, warming, or widespread extinction. Polyploidy may help species survive such upheavals. Van de Peer believes he may have finally solved the paradox."

"You can think of polyploidy, says Van de Peer, as a large-scale mutational event. "Once in a while something goes wrong, and you end up basically with a new cell with twice the amount of DNA than a normal plant cell." The species may do okay for a while, but this wholesale duplication of the genome has its baggage. More chromosomes can bog down cell division, introducing more opportunity for errors and"

Most organisms are diploid, but some plants have more than two chromosome sets due to whole-genome duplication, called polyploidy. Polyploidy can help species persist through extreme environmental stress, including major climate changes and widespread extinction events. It can also harm survival because extra chromosomes can slow cell division and increase opportunities for errors, potentially leading to extinction. Polyploidy is common in plants, creating a paradox. By examining ancient genome duplication events across several hundred plant species, genome duplications were found to cluster during periods of turmoil over the last 150 million years, including dramatic cooling, warming, and mass extinctions. This timing suggests polyploidy may provide an advantage during upheavals.

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