Most living things, including humans, have two sets of chromosomes—one from each parent. This condition is known as being diploid. But many plants aren’t so straightforward. For instance, strawberries boast eight sets of chromosomes. This unique trait, called polyploidy, occurs when a plant has more than two chromosome sets in its cells.
Polyploidy helps some plants survive extreme environmental changes, such as climate shifts. According to Yves Van de Peer, a plant biologist from Ghent University in Belgium, it allows species to adapt when conditions become harsh.
Interestingly, biologists had mixed feelings about polyploidy. They thought having double chromosomes might weaken a species. Yet, many plants carry this feature today, leading to what Van de Peer calls the “polyploidy paradox.” Why do so many plants have something that could threaten their survival?
In a recent study published in the journal Cell, Van de Peer and his team found answers. They looked at ancient genome duplication events across hundreds of plant species over 150 million years. Their findings revealed that these duplications occurred during significant disruptions in the Earth’s history, like extreme cooling or warming events. This suggests that polyploidy might be a survival strategy during upheaval times.
Van de Peer describes polyploidy as a major mutation event. Sometimes things might go awry in cell division, and a plant can end up with double the DNA. While this can lead to problems in cell division and mutations, it can also equip plants to thrive under stress.
The research determined that whole genome duplications aren’t random; they tend to cluster during specific times, especially during environmental crises. For instance, around 66 million years ago, an asteroid struck the Earth, leading to massive extinction events, including the disappearance of the dinosaurs. Surprisingly, many polyploid plants thrived despite such turmoil.
Van de Peer characterizes polyploid plants as “hopeful monsters,” able to excel under stress. They might even perform better in conditions like low light, as they can utilize more genes for photosynthesis. This gives them an edge over non-polyploid plants that didn’t survive these challenges.
Many may wonder about the practical implications of these findings. Pitta, a plant biotechnologist at Argentina’s National Scientific and Technical Research Council, emphasizes the relevance for modern plant breeding. If polyploid plants can resist various environmental stresses, this knowledge can aid in developing hardier crops.
The lessons from polyploids remind us that what seems like a disadvantage can turn into a strength. As climate change challenges our planet again, these resilient plants might just hold the key to adaptation.
For further reading on this topic, you can check out the original study in Cell here.
