Whole genome duplications in flowering plants may have provided evolutionary flexibility during mass extinction events, according to research examining how plants survived environmental crises over millions of years.
Plants with doubled genomes possess extra copies of all their genes, creating biological redundancy. This duplication allows genes to diverge and develop new functions while maintaining essential original processes. Researchers studying the evolutionary history of flowering plants found that genome duplications clustered around periods of major extinction events, suggesting the duplications enabled rapid adaptation to catastrophic environmental change.
The mechanism works through genetic slack. When an organism carries duplicate genes, one copy can continue performing its original role while the other experiments with new functions. During times of extreme stress, such as asteroid impacts or volcanic upheaval that altered climate and ecosystems, this flexibility becomes advantageous. Plants with duplicated genomes could evolve novel traits for surviving altered conditions faster than plants without this genetic redundancy.
Flowering plants show evidence of multiple ancient whole genome duplications throughout their evolutionary history. Some species carry three or more complete sets of chromosomes. These duplications are not unique to plants, but flowering plants appear particularly prone to this phenomenon.
The research reveals a counterintuitive insight: genetic complexity generated by duplication may buffer organisms against extinction rather than making them fragile. Traditional evolutionary theory emphasizes streamlining genomes for efficiency. This work suggests redundancy itself can be adaptive under extreme conditions.
The findings have implications for understanding plant resilience and could inform conservation strategies for modern species facing rapid climate change. Plants with greater genetic diversity or duplicated genomes might have inherent advantages in adapting to shifting environmental conditions.
However, the research examines correlation between duplication timing and extinction events. Proving causal relationships requires additional experimental work. Not all plants with duplicated genomes necessarily survived specific extinction events better than diploid counterparts, and other factors shaped plant survival during these periods.