A1 Journal article (refereed)
Fine scale diversity in the lava: genetic and phenotypic diversity in small populations of Arctic charr Salvelinus alpinus (2024)
Leblanc, C. A., Räsänen, K., Morrissey, M., Skúlason, S., Ferguson, M., & Kristjánsson, B. K. (2024). Fine scale diversity in the lava: genetic and phenotypic diversity in small populations of Arctic charr Salvelinus alpinus. BMC Ecology and Evolution, 24, Article 45. https://doi.org/10.1186/s12862-024-02232-3
JYU authors or editors
Publication details
All authors or editors: Leblanc, Camille A.; Räsänen, Katja; Morrissey, Michael; Skúlason, Skúli; Ferguson, Moira; Kristjánsson, Bjarni K.
Journal or series: BMC Ecology and Evolution
eISSN: 2730-7182
Publication year: 2024
Publication date: 15/04/2024
Volume: 24
Article number: 45
Publisher: BioMed Central
Publication country: United Kingdom
Publication language: English
DOI: https://doi.org/10.1186/s12862-024-02232-3
Publication open access: Openly available
Publication channel open access: Open Access channel
Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/94335
Abstract
A major goal in evolutionary biology is to understand the processes underlying phenotypic variation in nature. Commonly, studies have focused on large interconnected populations or populations found along strong environmental gradients. However, studies on small fragmented populations can give strong insight into evolutionary processes in relation to discrete ecological factors. Evolution in small populations is believed to be dominated by stochastic processes, but recent work shows that small populations can also display adaptive phenotypic variation, through for example plasticity and rapid adaptive evolution. Such evolution takes place even though there are strong signs of historical bottlenecks and genetic drift. Here we studied 24 small populations of the freshwater fish Arctic charr (Salvelinus alpinus) found in groundwater filled lava caves. Those populations were found within a few km2-area with no apparent water connections between them. We studied the relative contribution of neutral versus non-neutral evolutionary processes in shaping phenotypic divergence, by contrasting patterns of phenotypic and neutral genetic divergence across populations in relation to environmental measurements. This allowed us to model the proportion of phenotypic variance explained by the environment, taking in to account the observed neutral genetic structure.
Results
These populations originated from the nearby Lake Mývatn, and showed small population sizes with low genetic diversity. Phenotypic variation was mostly correlated with neutral genetic diversity with only a small environmental effect.
Conclusions
Phenotypic diversity in these cave populations appears to be largely the product of neutral processes, fitting the classical evolutionary expectations. However, the fact that neutral processes did not explain fully the phenotypic patterns suggests that further studies can increase our understanding on how neutral evolutionary processes can interact with other forces of selection at early stages of divergence. The accessibility of these populations has provided the opportunity for long-term monitoring of individual fish, allowing tracking how the environment can influence phenotypic and genetic divergence for shaping and maintaining diversity in small populations. Such studies are important, especially in freshwater, as habitat alteration is commonly breaking populations into smaller units, which may or may not be viable.
Keywords: populations; population biology; population genetics; population ecology; arctic char; phenotype; morphology (biology)
Free keywords: small population size; neutral processes; drift; phenotypic variation; morphology; lava cave; fish movement
Contributing organizations
Ministry reporting: Yes
Reporting Year: 2024
Preliminary JUFO rating: 2
