An extensive analysis of 470 species of flowering plants reveals that whole-genome duplications have surged during Earth’s turbulent environmental crises. This finding suggests that nature’s contingency plans are more evident than previously thought.
Chen et al. revealed that their study of 470 flowering plant genomes uncovered 132 ancient whole-genome duplication (WGD) events clustered around critical environmental changes. Image credit: Chen et al., doi: 10.1016/j.cell.2026.04.008.
Typically, organisms possess two sets of chromosomes, one inherited from each parent. However, many flowering plants exhibit additional sets due to random whole-genome duplications.
For instance, cultivated bananas often contain three sets of chromosomes, while wheat can display up to six sets, a phenomenon known as polyploidy.
Whole-genome duplications occur frequently in the plant kingdom, though they can impose significant costs.
Enlarged genomes demand greater nutrient resources, thereby heightening the risk of harmful mutations and potentially impacting fertility.
Consequently, only a limited fraction of the duplicated genome is retained and transmitted across generations in natural settings.
Conversely, genome duplication promotes genetic variation and may facilitate the evolution of new gene functions.
These genetic alterations can enhance an organism’s resilience against stresses like heat and drought.
“Whole genome duplication is typically viewed as an evolutionary dead end in stable environments,” notes Dr. Yves van de Peer, a researcher at Ghent University.
“However, in harsh conditions, it can yield unforeseen advantages.”
To discern why certain duplicate genomes endure, van de Peer and his team scrutinized the genomes of 470 flowering plant species, constructing one of the largest genomic datasets available.
They identified gene blocks that appear in nearly identical pairs, serving as markers for previous whole-genome duplication events.
Subsequently, they compared this data with findings from 44 plant fossils to estimate the timing of these duplications.
The analysis brought to light a notable pattern: genes that persist for extended durations predominantly originated from whole-genome duplications during significant periods of environmental upheaval.
These environmental events include a mass extinction caused by an asteroid 66 million years ago, various global cooling episodes that led to ecosystem collapses, and the Paleocene-Eocene Thermal Maximum (PETM) around 56 million years ago, characterized by rapid global warming.
This discovery sheds light on the enduring prevalence of polyploidy while underscoring the need for ongoing research into plant genomes throughout history.
In extreme conditions, polyploid plants may have acquired a competitive advantage.
Traits typically viewed as disadvantages, such as sustaining a larger and more intricate genome, might actually confer benefits in these contexts.
This study also offers insights into how plants may adapt to contemporary climate challenges.
During the PETM, global temperatures escalated by approximately 5 to 9 degrees Celsius over about 100,000 years—a warming trend comparable to that of today.
“While our current climate is warming at a much faster rate, insights from the past indicate that polyploidy could aid plants in navigating these challenging conditions,” concluded Dr. van de Peer.
For further details, check the study published on May 8 in the journal Cell.
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Chen et al.. Increase in polyploid populations during environmental cataclysms. Cell published online on May 8, 2026. doi: 10.1016/j.cell.2026.04.008
Source: www.sci.news
