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Aggression is a key determinant of fitness in many species, mediating access to mates, food and breeding sites. Variation in intrasexual aggression across species is likely to be driven by variation in resource availability and distribution. While males primarily compete over access to mates, females are likely to compete over resources to maximize offspring quantity and/or quality, such as food or breeding sites. To date, however, most studies have focused on male aggression, and we know little about drivers of female aggression across species. To investigate potential reproductive drivers of female aggression, we tested the relationship between three reproductive traits and aggression in eightDrosophilaspecies. Using machine learning classifiers developed forDrosophila melanogaster, we quantified aggressive behaviours displayed in the presence of yeast for mated and unmated females. We found that female aggression was correlated with ovariole number across species, suggesting that females who lay more eggs are more aggressive. A need for resources for egg production or oviposition sites may therefore be drivers of female aggression, though other potential hypotheses are discussed.
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Target species affects the duration of competitive interactions in the Neotropical dragonfly, Micrathyria atra (Odonata: Libellulidae)
Dragonflies often engage in aggressive interactions over access to mates, food, or other resources. We should expect species to have behavioral adaptations for minimizing such interactions with other species because they are not competing with them for mates and often require different resources. We conducted observational trials in natural water pools that provide new evidence for one such adaptation in the Neotropical dragonfly, Micrathyria atra: males in this species have shorter interactions with individuals of other species than with conspecifics.
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- Award ID(s):
- 1938843
- PAR ID:
- 10143317
- Date Published:
- Journal Name:
- Notulae odonatologicae
- Volume:
- 9
- Issue:
- 5
- ISSN:
- 0166-6584
- Page Range / eLocation ID:
- 173-177
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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