Limits...
Changes in selection regime cause loss of phenotypic plasticity in planktonic freshwater copepods.

Sereda SV, Wilke T, Schultheiß R - PLoS ONE (2014)

Bottom Line: Here we use the planktonic freshwater copepod Acanthodiaptomus denticornis from two lakes as model system to study UV stress responses of two phenotypically different populations under laboratory conditions.Our study reveals heritable lake- and sex-specific differences of behaviour, physiological plasticity, and mortality.We discuss specific selective scenarios causing these differences and argue that phenotypic plasticity will be higher when selection pressure is moderate, but will decrease or even be lost under stronger pressure.

View Article: PubMed Central - PubMed

Affiliation: Department of Animal Ecology and Systematics, Justus Liebig University Giessen, Giessen, Germany.

ABSTRACT
Rapid phenotypic adaptation is critical for populations facing environmental changes and can be facilitated by phenotypic plasticity in the selected traits. Whereas recurrent environmental fluctuations can favour the maintenance or de novo evolution of plasticity, strong selection is hypothesized to decrease plasticity or even fix the trait (genetic assimilation). Despite advances in the theoretical understanding of the impact of plasticity on diversification processes, comparatively little empirical data of populations undergoing diversification mediated by plasticity are available. Here we use the planktonic freshwater copepod Acanthodiaptomus denticornis from two lakes as model system to study UV stress responses of two phenotypically different populations under laboratory conditions. Our study reveals heritable lake- and sex-specific differences of behaviour, physiological plasticity, and mortality. We discuss specific selective scenarios causing these differences and argue that phenotypic plasticity will be higher when selection pressure is moderate, but will decrease or even be lost under stronger pressure.

Show MeSH

Related in: MedlinePlus

Changes of carotenoid content in A. denticornis.Empty circles refer to negative controls; black circles refer to UV exposed animals. Numbers above each point correspond to the number of animals in the respective batch of ethanol extract. A rise in astaxanthin content was only observed in LP males. In both populations males had higher concentrations of astaxanthin than females.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3935978&req=5

pone-0090010-g002: Changes of carotenoid content in A. denticornis.Empty circles refer to negative controls; black circles refer to UV exposed animals. Numbers above each point correspond to the number of animals in the respective batch of ethanol extract. A rise in astaxanthin content was only observed in LP males. In both populations males had higher concentrations of astaxanthin than females.

Mentions: This clear taxonomic identification notwithstanding, we found a hitherto unreported sexual dimorphism in the LP population with brightly red coloured males but translucent females (Figs 1 and 2; see section ‘Physiological response to UV’ below). This observation was confirmed during our second visit to LP in May 2012. In contrast, both sexes in LM were translucent as previously reported in the literature.


Changes in selection regime cause loss of phenotypic plasticity in planktonic freshwater copepods.

Sereda SV, Wilke T, Schultheiß R - PLoS ONE (2014)

Changes of carotenoid content in A. denticornis.Empty circles refer to negative controls; black circles refer to UV exposed animals. Numbers above each point correspond to the number of animals in the respective batch of ethanol extract. A rise in astaxanthin content was only observed in LP males. In both populations males had higher concentrations of astaxanthin than females.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3935978&req=5

pone-0090010-g002: Changes of carotenoid content in A. denticornis.Empty circles refer to negative controls; black circles refer to UV exposed animals. Numbers above each point correspond to the number of animals in the respective batch of ethanol extract. A rise in astaxanthin content was only observed in LP males. In both populations males had higher concentrations of astaxanthin than females.
Mentions: This clear taxonomic identification notwithstanding, we found a hitherto unreported sexual dimorphism in the LP population with brightly red coloured males but translucent females (Figs 1 and 2; see section ‘Physiological response to UV’ below). This observation was confirmed during our second visit to LP in May 2012. In contrast, both sexes in LM were translucent as previously reported in the literature.

Bottom Line: Here we use the planktonic freshwater copepod Acanthodiaptomus denticornis from two lakes as model system to study UV stress responses of two phenotypically different populations under laboratory conditions.Our study reveals heritable lake- and sex-specific differences of behaviour, physiological plasticity, and mortality.We discuss specific selective scenarios causing these differences and argue that phenotypic plasticity will be higher when selection pressure is moderate, but will decrease or even be lost under stronger pressure.

View Article: PubMed Central - PubMed

Affiliation: Department of Animal Ecology and Systematics, Justus Liebig University Giessen, Giessen, Germany.

ABSTRACT
Rapid phenotypic adaptation is critical for populations facing environmental changes and can be facilitated by phenotypic plasticity in the selected traits. Whereas recurrent environmental fluctuations can favour the maintenance or de novo evolution of plasticity, strong selection is hypothesized to decrease plasticity or even fix the trait (genetic assimilation). Despite advances in the theoretical understanding of the impact of plasticity on diversification processes, comparatively little empirical data of populations undergoing diversification mediated by plasticity are available. Here we use the planktonic freshwater copepod Acanthodiaptomus denticornis from two lakes as model system to study UV stress responses of two phenotypically different populations under laboratory conditions. Our study reveals heritable lake- and sex-specific differences of behaviour, physiological plasticity, and mortality. We discuss specific selective scenarios causing these differences and argue that phenotypic plasticity will be higher when selection pressure is moderate, but will decrease or even be lost under stronger pressure.

Show MeSH
Related in: MedlinePlus