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Rapid evolution leads to differential population dynamics and top-down control in resurrected Daphnia populations.

ABSTRACT: There is growing evidence of rapid genetic adaptation of natural populations to environmental change, opening the perspective that evolutionary trait change may subsequently impact ecological processes such as population dynamics, community composition, and ecosystem functioning. To study such eco-evolutionary feedbacks in natural populations, however, requires samples across time. Here, we capitalize on a resurrection ecology study that documented rapid and adaptive evolution in a natural population of the water flea Daphnia magna in response to strong changes in predation pressure by fish, and carry out a follow-up mesocosm experiment to test whether the observed genetic changes influence population dynamics and top-down control of phytoplankton. We inoculated populations of the water flea D. magna derived from three time periods of the same natural population known to have genetically adapted to changes in predation pressure in replicate mesocosms and monitored both Daphnia population densities and phytoplankton biomass in the presence and absence of fish. Our results revealed differences in population dynamics and top-down control of algae between mesocosms harboring populations from the time period before, during, and after a peak in fish predation pressure caused by human fish stocking. The differences, however, deviated from our a priori expectations. An S-map approach on time series revealed that the interactions between adults and juveniles strongly impacted the dynamics of populations and their top-down control on algae in the mesocosms, and that the strength of these interactions was modulated by rapid evolution as it occurred in nature. Our study provides an example of an evolutionary response that fundamentally alters the processes structuring population dynamics and impacts ecosystem features.

SUBMITTER: Goitom E

PROVIDER: S-EPMC5748522 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Rapid evolution leads to differential population dynamics and top-down control in resurrected <i>Daphnia</i> populations.

Goitom Eyerusalem E Kilsdonk Laurens J LJ Brans Kristien K Jansen Mieke M Lemmens Pieter P De Meester Luc L

Evolutionary applications 20171115 1

There is growing evidence of rapid genetic adaptation of natural populations to environmental change, opening the perspective that evolutionary trait change may subsequently impact ecological processes such as population dynamics, community composition, and ecosystem functioning. To study such eco-evolutionary feedbacks in natural populations, however, requires samples across time. Here, we capitalize on a resurrection ecology study that documented rapid and adaptive evolution in a natural popul ...[more]

PMID: 29302275

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Dataset Information

Rapid evolution leads to differential population dynamics and top-down control in resurrected Daphnia populations.

Publications

Rapid evolution leads to differential population dynamics and top-down control in resurrected <i>Daphnia</i> populations.

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