rapid evolution; coevolutionary dynamics; eco-evolutionary dynamics; genomics of adaptation
Retel Cas, Kowallik Vienna, Huang Weini, Werner Benjamin, Künzel Sven, Becks Lutz, Feulner Philine G. D. (2019), The feedback between selection and demography shapes genomic diversity during coevolution, in
Science Advances, 5(10), eaax0530-eaax0530.
Retel Cas, Märkle Hanna, Becks Lutz, Feulner Philine (2019), Ecological and Evolutionary Processes Shaping Viral Genetic Diversity, in
Viruses, 11(3), 220-220.
Frickel Jens, Feulner Philine G. D., Karakoc Emre, Becks Lutz (2018), Population size changes and selection drive patterns of parallel evolution in a host–virus system, in
Nature Communications, 9(1), 1706-1706.
| Author |
Frickel, J; Feulner, PGD; Karakoc, E; Becks, L |
| Publication date |
18.06.2018 |
| Persistent Identifier (PID) |
https://doi.org/10.5061/dryad.4gf1qb7 |
| Repository |
Dryad
|
| Abstract |
Predicting the repeatability of evolution remains elusive. Theory and empirical studies suggest that strong selection and large population sizes increase the probability for parallel evolution at the phenotypic and genotypic levels. However, selection and population sizes are not constant, but rather change continuously and directly affect each other even on short time scales. Here, we examine the degree of parallel evolution shaped through eco-evolutionary dynamics in an algal host population coevolving with a virus. We find high degrees of parallelism at the level of population size changes (ecology) and at the phenotypic level between replicated populations. At the genomic level, we find evidence for parallelism, as the same large genomic region was duplicated in all replicated populations, but also substantial novel sequence divergence between replicates. These patterns of genome evolution can be explained by considering population size changes as an important driver of rapid evolution.
NCBI PRJNA450514
| Author |
Frickel, Jens |
| Publication date |
17.04.2018 |
| Persistent Identifier (PID) |
PRJNA450514 |
| Repository |
NCBI SRA
|
|
NCBI PRJNA548271
| Author |
Retel, Cas |
| Publication date |
11.06.2019 |
| Persistent Identifier (PID) |
PRJNA548271 |
| Repository |
NCBI SRA
|
|
There is a continuing interest to identify beneficial mutations in the genome. This interest is fuelled by the question regarding the genetic basis of adaptive traits and the need to understand the temporal dynamics of adaptive evolution, i.e., how frequent adaptive changes are and what influences the rate of change. In the project proposed here, we aim to (1) identify rapid adaptive genomic changes in coevolving host-virus populations and (2) comprehend how the dynamics of adaptive change vary with changing demographic setting. Previous experiments with chemostat systems showed that host and virus rapidly evolved resistance and counter adaptation. Later in the experiments, the dynamics shifted from arms race dynamics to fluctuating selection, after a generalist host resistant to all virus populations had evolved. The virus population however did not go extinct due to a trade-off between resistance and growth rates. A key observation is that the evolutionary dynamics in this system are coupled to demographic changes: during the initial arms race dynamics, host and virus population sizes cycle, with dramatic population size reductions, while population size are more steady when the evolutionary dynamics are characterized by fluctuating selection. The entanglement of the coevolutionary and population size dynamics (eco-evolutionary dynamics) makes this an excellent system for the proposed work. Following the described dynamics with whole genome sequencing of both (host and virus) populations across different time points will allow us to identify candidate mutations under selection. The experiments are replicated and fitness of the populations and individual clones at different time can be assessed. In addition, mutations can be traced over time estimating the probability and time to fixation of adaptive changes, providing a picture of the dynamics of adaptive change, in both interacting populations. In a second step, we will vary the experimental setup manipulating selection and demography in a full factorial design and evaluating how this alters the dynamics of adaptive change. Hence, we will improve our understanding on the relative role of two important processes selection and demography within eco-evolutionary dynamics. Furthermore, this project will aid to the knowledge on how to reveal the underlying processes from the observed genomic diversity patterns. An issue of major concern in population genomics, which aims to infer genomic regions, influenced by local adaptation from genome-wide polymorphism data. Hence, our results will also inform method development, which is essential as none of the statistical methods so far is robust under non-equilibrium situations, i.e. fluctuations in population sizes. Therefore, results from this experimental work will in the future aid population genomic inferences in other systems with longer generation times.