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Published on: June 11, 2020
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EVOLUTION OF STARVATION RESISTANCE IN DROSOPHILA MELANOGASTER: ASPECTS OF METABOLISM AND COUNTER-IMPACT SELECTION
Lawrence G Harshman1, Jeana L Schmid1
1School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, 68588.
Summary
Artificial selection increased starvation resistance in fruit flies (Drosophila melanogaster). Selected females resisted starvation
Area of Science:
- Evolutionary Biology
- Animal Physiology
Background:
- Artificial selection experiments are used to study adaptation.
- Starvation resistance is a key survival trait influenced by metabolic rate and enzyme activity.
Purpose of the Study:
- To investigate the genetic basis of starvation resistance in Drosophila melanogaster.
- To test the hypothesis that reduced metabolic rate underlies increased stress resistance.
- To examine changes in intermediary metabolism enzyme activity during starvation.
Main Methods:
- Artificial selection for starvation resistance in fruit flies over 15 generations.
- Measurement of respiration rates in selected and control lines.
- Assay of intermediary metabolism enzyme activities in response to starvation.
Main Results:
- Females showed rapid response to selection for starvation resistance, while males responded later.
- No correlation was found between starvation resistance and respiration rate.
- Selected females exhibited resistance to the decrease in enzyme activity typically induced by starvation.
Conclusions:
- Reduced metabolic rate is not the mechanism for increased starvation resistance in this study.
- Selected females may have evolved to counteract the phenotypic effects of starvation stress.
- The findings support the concept of counter-impact selection in evolutionary studies.
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