Stockholm, Sweden – June 2025 — In a groundbreaking study published in the journal Nature Ecology & Evolution, researchers from Stockholm University have uncovered how genetic diversity within a species influences its ability to adapt to a warming climate. The study, which used yeast as a model organism, sheds light on fundamental evolutionary dynamics with broad implications for biodiversity conservation in the face of global warming.
The research, led by Professors Marina Rafajlović and Henrik Hallin, utilized experimental evolution techniques to simulate warming environmental conditions in controlled yeast populations. By analyzing how genetically diverse versus genetically uniform populations responded to rising temperatures, the team was able to pinpoint the crucial role of standing genetic variation in facilitating rapid adaptation.
"Genetic diversity functions as a reservoir of adaptive potential," said Rafajlović. "Our results demonstrate that populations with greater initial genetic variation are significantly more likely to evolve increased heat tolerance over relatively short timescales."
The study also identified specific genetic mechanisms underlying this adaptation, including changes in gene regulation and protein function. These molecular insights suggest that even single-celled organisms like yeast harbor complex adaptive strategies that could inform our understanding of resilience in higher organisms, including plants and animals.
Importantly, the findings underscore the risks associated with reduced genetic variation in wild populations, whether due to habitat fragmentation, inbreeding, or human-induced environmental change. Conservation policies, the researchers argue, should prioritize maintaining and enhancing genetic diversity to bolster the long-term survival of species under climate stress.
The work was conducted in collaboration with scientists from Uppsala University and the University of Gothenburg, and received funding from the Swedish Research Council and the European Union’s Horizon program.
This study provides a timely reminder of evolution’s role in shaping how life on Earth will respond to our rapidly changing planet—and why preserving nature’s genetic richness is more critical than ever.