Tag Archives: flowering

How Duplicated Genomes Aided Flowering Plants in Surviving the End-Cretaceous Mass Extinction

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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

New genetic research on flowering plants changes the tree of life at a large scale

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The pink lapacho tree is one of approximately 300,000 species of flowering plants

Roberto Okamura Tetsuo/Shutterstock

Botanists have used genome data from more than 9,500 species to map evolutionary relationships among flowering plants. The newly compiled Tree of Life will help scientists piece together the origins of flowering plants and inform future conservation efforts.

Approximately 90 percent of plants that live on land are flowering and fruiting plants called angiosperms. These flowering plants are essential to maintaining Earth's ecosystems, including storing carbon and producing oxygen, and they make up a large portion of our diet.

“Our very existence depends on them,” he says. william baker At the Royal Botanic Gardens in Kew, England. “That's why we need to really understand them.”

For the past eight years, Baker and his colleagues have been working to complete the Tree of Life, which describes the evolutionary relationships between all genera of plants and fungi.

Starting with flowering plants, the researchers designed molecular probes to search for 353 specific genes found in the nucleus of all angiosperms. “The nuclear genome is huge,” Baker says. “So we needed to focus on a specific set of genes.”

Researchers have so far sequenced the genes of 9,506 species of flowering plants, primarily using specimens from collections and public databases around the world. This represents nearly all known angiosperm families and approximately 8,000 of the 13,400 recorded genera.Some of the specimens collected in the analysis are more than 200 years old; Arenaria globifloraand many Guadalupe Island olives (Espererea Palmeri).

By comparing the similarities in the gene sequences of different flowering plants, researchers were able to figure out where they fit on the tree of life.

Baker says this is the most comprehensive survey of angiosperms to date. “We often liken it to the periodic table of elements,” he says. “It's the basic framework for life.”

angiosperm tree of life

Royal Botanic Gardens, Kew

Angiosperms emerged about 140 million years ago and have rapidly flourished, overtaking flowerless gymnosperms to become the world's dominant plant species. The sudden appearance of the diversity of flowering plants in the fossil record has baffled scientists for the past few centuries, and Charles Darwin called it “a hideous mystery.”

Now, the Tree of Life confirms that about 80 percent of the major flowering plant lineages that still exist today were part of this early boom in angiosperm diversity. “We can't say we've solved this 'damn mystery,' but at least we can say it really does exist,” Baker said.

The tree of life also highlights a further surge in diversity that occurred around 40 million years ago, possibly caused by a drop in global temperatures at the time.

In the future, he says, the Tree of Life could also help in the search for plants with pharmaceutical properties for new drugs. Ilia Leech, another member of Cue's team. It also helps scientists identify new species and assess which species are most vulnerable to climate change.

“This is the latest and greatest evolutionary framework for conducting new research that approaches the mechanisms that have allowed flowering plants to take over the world,” he says. ryan falk at Mississippi State University.

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Source: www.newscientist.com