Periodic Reporting for period 2 - CLIMEVOLVE (Evolution and mechanisms of thermal performance – answers through artificial selection in zebrafish)
Période du rapport: 2023-03-01 au 2023-12-31
The ERC CLIMEVOLVE project aims at understanding evolution of thermal performance. It is investigating how rapidly and by which mechanisms fish adapt to warming water temperatures.
Climate change is one of the most severe global threats of our time. The task now facing biologists is to predict how life on earth will be affected. Ectothermic animals, whose body temperature is controlled by the environment, are particularly sensitive to warming because the rate of their biological processes is largely under environmental control. For many decades, scientists have studied how fish and other ectothermic animals adjust their physiology to better function at new temperatures. This is a reversible process within individuals called thermal acclimation, and the rates and mechanisms of thermal acclimation are partly understood. However, the process of evolutionary adaptation across generations has not been well studied in vertebrates, partly due to the difficulty of maintaining experiments across many generations. This project aims at uncovering the potential for evolutionary rescue to climate change impacts, by using three sets of evolution experiments. Two are multi-generational artificial selection experiments on zebrafish. The third is a natural evolution experiment that has taken polace on Iceland over the last thousands of years as sticklebacks have adapted to warm water in several geothermally heated lakes.
The main objectives are:
1. Understand the physiology behind warming tolerance
2. Measure how fast climate change evolution can be
3. Compare laboratory evolution experiments on zebrafish with the natural stickleback experiments
4. Discover the genetics behind climate change evolution
By answering these important questions, this project will substantially move the field of thermal biology forward. We will gain knowledge needed to understand and predict climate change impacts on fish, insights that will help focusing conservation efforts.
Climate change is one of the most severe global threats of our time. The task now facing biologists is to predict how life on earth will be affected. Ectothermic animals, whose body temperature is controlled by the environment, are particularly sensitive to warming because the rate of their biological processes is largely under environmental control. For many decades, scientists have studied how fish and other ectothermic animals adjust their physiology to better function at new temperatures. This is a reversible process within individuals called thermal acclimation, and the rates and mechanisms of thermal acclimation are partly understood. However, the process of evolutionary adaptation across generations has not been well studied in vertebrates, partly due to the difficulty of maintaining experiments across many generations. This project aims at uncovering the potential for evolutionary rescue to climate change impacts, by using three sets of evolution experiments. Two are multi-generational artificial selection experiments on zebrafish. The third is a natural evolution experiment that has taken polace on Iceland over the last thousands of years as sticklebacks have adapted to warm water in several geothermally heated lakes.
The main objectives are:
1. Understand the physiology behind warming tolerance
2. Measure how fast climate change evolution can be
3. Compare laboratory evolution experiments on zebrafish with the natural stickleback experiments
4. Discover the genetics behind climate change evolution
By answering these important questions, this project will substantially move the field of thermal biology forward. We will gain knowledge needed to understand and predict climate change impacts on fish, insights that will help focusing conservation efforts.
The project was off to a slow start due to the covid pandemic, but is now progressing nicely. We have finished examining the effect of evolution towards higher acute thermal tolerance in zebrafish. These unique fish lines were developed through artificial selection in a previous project, and have now been examined physiologically.
The main selection experiment is testing if it is possible to shift the thermal performance curves for zebrafish populations towards colder and warmer temperatures. It uses artificial selection over many generations of zebrafish, and by selecting and reproducing the individuals with the desired traits within each population the traits evolve. As the experiment is half way through, it is already allowing us to measure the progress of the evolutionary process.
The second fish species used in the project, three-spined sticklebacks, are found in geothermally heated lakes on Iceland. This part of the CLIMEVOLVE project will examine how warming over millennia have altered the warm adapted populations, and will commence during 2024.
The final part of the project is the investigation into the genetic underpinnings of the thermal evolution observed in the various zebrafish populations. This is currently ongoing.
The main selection experiment is testing if it is possible to shift the thermal performance curves for zebrafish populations towards colder and warmer temperatures. It uses artificial selection over many generations of zebrafish, and by selecting and reproducing the individuals with the desired traits within each population the traits evolve. As the experiment is half way through, it is already allowing us to measure the progress of the evolutionary process.
The second fish species used in the project, three-spined sticklebacks, are found in geothermally heated lakes on Iceland. This part of the CLIMEVOLVE project will examine how warming over millennia have altered the warm adapted populations, and will commence during 2024.
The final part of the project is the investigation into the genetic underpinnings of the thermal evolution observed in the various zebrafish populations. This is currently ongoing.