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Measurement of Lifespan in Drosophila melanogaster
Published on: January 7, 2013
Social facilitation of selective mortality.
Mark I McCormick1, Mark G Meekan
1School of Marine and Tropical Biology, James Cook University, Townsville, Queensland 4811, Australia. mark.mccormick@jcu.edu.au
Ecology
|July 3, 2007
Summary
Male damselfish territoriality protects juvenile fish from predators. This defense alters predator access, leading to size-dependent survival shifts for young damselfish within territories.
Area of Science:
- Marine Ecology
- Behavioral Ecology
- Population Dynamics
Background:
- Territoriality in breeding fish can influence resource availability and species distribution.
- Predator-prey interactions are key drivers of juvenile survival and population structure.
Purpose of the Study:
- To investigate how male damselfish territorial defense impacts conspecific juvenile survival.
- To determine if territoriality alters predation selectivity on newly settled juveniles.
- To understand the indirect effects of territorial behavior on predator access and prey selection.
Main Methods:
- Monitoring survival of tagged juvenile damselfish (Pomacentrus amboinensis) placed inside and outside male territories.
- Behavioral observations of predator species (moonwrasse, dottyback) within territories.
- Experimental removal of a key predator (dottyback) to assess its impact on juvenile survival.
Main Results:
- Juvenile damselfish survival was indirectly facilitated by male territorial defense.
- Predation selectivity shifted: larger juveniles had lower survival within territories, unlike outside.
- Male damselfish aggression altered predator access, favoring dottybacks over moonwrasses within territories.
Conclusions:
- Male territoriality creates spatial patchiness in predation selective pressures.
- Interactions between resident breeders and intruders shape predator communities and their impact.
- This patchiness in predator pressure influences juvenile distribution and phenotypic traits.
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