Many organisms, including plants and some animals, have more than two sets of chromosomes. These organisms are known as polyploids. Whole-genome duplications have played an essential role in creating new species and driving evolution. There’s some evidence that polyploids might have advantages, especially when the environment is unstable. Many ancient polyploid events occurred during extreme climate shifts, and today’s polyploids often thrive in tougher environments than their ancestors. However, most new polyploids don’t survive very well.
To understand why some polyploids succeed while others fail, we look at three main questions: (1) what causes polyploidy, (2) what helps newly formed polyploids survive, and (3) how they stabilize their populations over time. This research project covers all these areas, examining the genetic and evolutionary factors involved.
We are taking a broad approach, studying both plants and animals. Our primary models are the plant Arabidopsis lyrata, found in the Northern Hemisphere, and the burrowing frogs Neobatrachus, found in Australia. Both models vary in ploidy and environmental occurrence. This study combines traditional genetics with modern genomic techniques and analyzes data from natural history collections around the world.
Specifically, we aim (1) to identify genetic and environmental factors that lead to polyploidy by examining variations in the formation of unreduced gametes, (2) to investigate how polyploids manage to stabilize their fertility through selection, and (3) to explore how polyploid populations recover after they face challenges, by looking at patterns of introgression or genetic mixing.
Understanding how polyploidy works across different species can lead to important breakthroughs in biology, agriculture, and medicine.