SFI External Professor Andreas Wagner (University of Zurich) was recently awarded the European Research Council’s Advanced Grant to study fitness landscapes in evolutionary biology. The ERC Advanced Grant is extremely competitive and has only become more so in recent years as funding opportunities shrink. Wagner’s award — EUR 2.5 million over five years — will help support the SEASCAPES project, which will explore a paradox in evolutionary biology theory.
Imagine every possible version of a gene laid out next to its close relatives, such that genes one mutation away from each other are neighbors. This is what evolutionary biologists call a fitness landscape, and it's historically been an important area of study at SFI. On this landscape, every location corresponds to a different genetic variant. Higher and lower elevations represent the “fitness” of organisms with these different genes.
Recent experiments reveal that fitness landscapes are often rugged, characterized by many peaks of varied heights that, crucially, are separated by valleys that natural selection cannot traverse: Natural selection is like a hiker who can only go uphill. This suggests organisms would get stuck at local maxima, incapable of evolving toward the highest peaks. But Darwinian evolution nonetheless produces highly adapted organisms. How can this be?
One possibility Wagner proposes is that environmental change creates dynamically changing landscapes — a seascape. In a seascape, genetic variants become more and less fit when the environment shifts, making them go up and down like waves rising and falling. Another possibility is that weakly selected or neutral mutations act like stepping stones and allow organisms to ascend to higher peaks nearby.
The researchers will use genome editing, growth-rate measurements in E.coli, and AI to map up to 100 trillion genotypes and analyze study systems like proteins and regulatory DNA. Wagner believes this research could have strong implications in fields like medicine and protein engineering.