Can past selection affect future adaptive potential?
Main funder
Funder's project number: 328953
Funds granted by main funder (€)
- 299 562,00
Funding program
Project timetable
Project start date: 01/09/2019
Project end date: 31/08/2022
Summary
The genetic basis of adaptive potential is a fundamental question in evolutionary biology and the question also has a great applied value. To manage natural resources and conserve species under growing human pressure, it is critically important to assess and understand how human activities affect species’ adaptive potential. Human-induced changes in the molecular components of adaptive potential in natural populations have remained poorly studied because 1) we lack information of the relative contribution of different molecular components to the adaptive potential, 2) changes in adaptive potential caused by human activities remain difficult to demonstrate in nature, where environment is constantly changing, and 3) molecular level changes are difficult to study in non-model organisms. Being unsure what we are looking for has hindered the development of an effective and practical genomic tool to identify human-induced changes in adaptive potential. I use size-selective fisheries as an example of pervasive anthropogenic activity that can erode population’s adaptive potential. I have experimentally harvested zebrafish populations for five generations and induced phenotypic and genetic changes in them. After that, the populations were allowed to recover (i.e., no harvesting) for 10 generations. I will use these unique, long-term selection lines and the latest next-generation sequencing techniques to test whether five generations of size-selective harvesting have affected the components of adaptive potential and whether these effects have eroded during the recovery period. I will focus on sequence-level (coding and non-coding) variation, epigenetic variation, gene networks and within-generation plasticity. I will finally expose the experimental populations to re-harvesting and to a combination of re-harvesting and climate change related disturbance. No study thus far has empirically investigated how the exploited populations respond to the re-start of fishing after recovery or how fisheries selection and climate change interact. Furthermore, studies focusing on the persistency of molecular changes induced by size-selective harvesting are rare, although they could give practical information about the recovery timelines and help validating eco-evolutionary models. My additional goal is to improve the communication between researchers and managers because the practical value of genomics for fisheries management and conservation could be greater than it currently is.
