Female competitive behaviors during courtship can have substantial fitness consequences, yet we know little about the physiological and social mechanisms underlying these behaviors—particularly for females of polygynous lek mating species. We explored the hormonal and social drivers of female intersexual and intrasexual behavior during courtship by males in a captive population of Indian peafowl. We investigated whether (1) female non-stress induced circulating estradiol (E2) and corticosterone (CORT) levels or (2) female dominance status in a dyad predicts female solicitation behavior. We also tested whether female circulating E2 and CORT predict dominant females’ aggressive behaviors toward subordinate females in the courtship context. Our findings demonstrate that females with higher levels of circulating E2 as well as higher levels of circulating CORT solicit more courtships from males. Dominant females also solicit more courtships from males than subordinate females. Female intrasexual aggressive behaviors during courtship, however, were not associated with circulating levels of E2 or CORT. Overall, we conclude that circulating steroid hormones in conjunction with social dominance might play a role in mediating female behaviors associated with competition for mates. Experimental manipulation and measures of hormonal flexibility throughout the breeding season in relation to competitive and sexual behaviors will be necessary to further examine the link between hormonal mechanisms and female behavior in polygynous lekking systems.
Exposure to multiple environmental stressors is a common occurrence that can affect organisms in predictable or unpredictable ways. Hypoxia and turbidity in aquatic environments are 2 stressors that can affect reproductive behaviors by altering energy availability and the visual environment, respectively. Here we examine the relative effects of population and the rearing environment (oxygen concentration and turbidity) on reproductive behaviors. We reared cichlid fish (the Egyptian mouthbrooder, Pseudocrenilabrus multicolor) from 2 populations (a swamp and river) until sexual maturity, in a full factorial design (hypoxic/normoxic × clear/turbid) and then quantified male competitive and courtship behaviors and female preference under their respective rearing conditions. Overall, we found that the rearing environment was more important than population for determining behavior, indicating there were few heritable differences in reproductive behavior between the 2 populations. Unexpectedly, males in the hypoxic rearing treatment performed more competitive and courtship behaviors. Under turbid conditions, males performed fewer competitive and courtship behaviors. We predicted that females would prefer males from their own population. However, under the hypoxic and turbid combination females from both populations preferred males from the other population. Our results suggest that reproductive behaviors are affected by interactions among male traits, female preferences, and environmental conditions.
more » « less- NSF-PAR ID:
- 10524980
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Current Zoology
- ISSN:
- 1674-5507
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract How populations adapt, or not, to rapid evolution of sexual signals has important implications for population viability, but is difficult to assess due to the paucity of examples of sexual signals evolving in real time. In Hawaiian populations of the Pacific field cricket (
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Abstract Male mating strategies respond to female availability such that variation in resources that affect spatial distribution can also alter cost–benefit tradeoffs within a population. In arid‐adapted species, rainfall alters reproduction, behavior, morphology, and population density such that populations differing in resource availability may also differ in successful reproductive strategies. Here, we compare two populations of Cape ground squirrels (
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Abstract Environmental microbes have the potential to be involved in nearly all behavioural processes. For example, mating systems where males use intromittent organs to transfer sperm to females represent a means by which environmental microbes collected by males can breach entry into females' body cavities during mating. However, the degree to which the acquisition of environmental microbes onto important sex structures alters courtship behaviours remains unknown. Here, we collected bacteria from the copulatory organs of
Agelenopsis pennsylvanica funnel‐weaving spiders in situ to test whether exposure to bacteria on copulatory organs can alter hosts' courtship behaviour, reproductive success and survival. We used a standardized assay to repeatedly measure each spider's aggressiveness, a behavioural component of both male courtship and female sexual receptivity. Then, we experimentally altered the bacteria present on male and female spiders' copulatory organs with an application of either (a) a mixture of bacteria collected from conspecifics to increase bacterial presence, (b) an antibiotic to reduce bacterial presence or (c) a procedural control. Each spider was paired with a size‐matched spider of the opposite sex whose copulatory organs were unaltered, and we measured the latency until the onset and the duration of courtship. Spiders were then isolated, and we measured each individual's time until death and female fecundity over the next 40 days. We found that female exposure to bacteria had multiple effects on mating dynamics. Males took over four times longer to begin courting females that had been exposed to bacteria compared to unexposed and antibiotic‐treated females. Only when courting these bacteria‐exposed females, males began courtship sooner when females were more aggressive. Lastly, females whose mate had been exposed to bacteria experienced reduced survival. These data suggest that bacteria present on animals' copulatory organs can alter courtship behaviours, female survivorship, and may potentially play a role in mating dynamics. -
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