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Asexual reproduction changes predator population dynamics in a life predator-prey system
Thomas Scheuerl1, Claus-Peter Stelzer1
1Research Institute for Limnology, University of Innsbruck Mondsee Austria.
Population Ecology
|November 5, 2020
Summary
Organism population cycles can be influenced by reproductive strategies. Obligate parthenogens (OPs) exhibited increased population cycle amplitudes compared to cyclical parthenogens (CPs) under low nutrient conditions.
Area of Science:
- Ecology
- Population Dynamics
- Evolutionary Biology
Background:
- Organisms exhibit population size oscillations, often driven by predator-prey interactions.
- Rotifer-algae communities (Brachionus calyciflorus - Chlorella vulgaris) are model systems for studying population dynamics.
- Brachionus calyciflorus exhibits cyclical parthenogenesis (CP), with varying sexual propensity among clones.
Purpose of the Study:
- To investigate how different reproductive modes (cyclical vs. obligate parthenogenesis) affect population oscillations in Brachionus calyciflorus.
- To test the hypothesis that sexual propensity influences population dynamics and cycle amplitudes.
Main Methods:
- Studied the population dynamics of Brachionus calyciflorus clones with different reproductive strategies: cyclical parthenogens (CPs) and obligate parthenogens (OPs).
- Monitored population cycle amplitudes and other dynamic parameters under controlled conditions, specifically at low nutrient levels.
Main Results:
- Obligate parthenogens (OPs) showed increased amplitudes in population cycles compared to cyclical parthenogens (CPs) when nutrient levels were low.
- Most other population dynamic parameters were not significantly affected by the reproductive mode.
Conclusions:
- Reproductive mode, specifically the difference between cyclical and obligate parthenogenesis, can significantly impact population oscillation amplitudes.
- Sexual propensity and reproductive strategy should be considered as crucial variables in future ecological population dynamics research.
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