Aggression, reproduction, and androgens in wild dwarf mongooses: a test of the challenge hypothesis
Article Abstract:
Testosterone (androgen), once considered a hormone controlling the changes in male reproductive physiology, seems to be associated more with the temporal pattern of aggressive and paternal behavior. At the beginning of the breeding season, the testosterone levels in all species rise from a nonbreeding baseline to a slightly higher breeding baseline. Though these levels of testosterone are sufficient for normal reproductive physiology and behavior, they are not sufficient to stimulate the male-male aggressive and mate guarding behavior. The data obtained from eight packs of dwarf mongooses shows that androgen levels are raised above the breeding baseline only during mating periods and aggression, as the mongooses show considerable paternal care of young with peaks of male-male aggression during mating periods.
Publication Name: The American Naturalist
Subject: Earth sciences
ISSN: 0003-0147
Year: 1993
User Contributions:
Comment about this article or add new information about this topic:
Hormones and life histories: an integrative approach
Article Abstract:
The role of hormones in animal behavior and ecology was investigated. Hormonal studies were presented as especially suited for studies to investigate the endocrine basis for life-history trade-offs, whether natural selection acts on organisms or particular traits and adaptive alterations in mating systems and social organization. Phenotypic engineering was demonstrated by altering the plasma testosterone of free-living dark-eyed juncos (Junco hyemalis) and observing for effects on physiology and behavior.
Publication Name: The American Naturalist
Subject: Earth sciences
ISSN: 0003-0147
Year: 1992
User Contributions:
Comment about this article or add new information about this topic:
Testosterone and avian life histories: effects of experimentally elevated testosterone on behavior and correlates of fitness in the dark-eyed junco (junco hyemalis)
Article Abstract:
Research shows that testosterone administration partially restricts paternal behavior and increases the frequency of song among adult male dark-eyed juncos. Nine fitness parameters were compared for treated experimental males and non-treated control males with no significant variations. The study showed that male parental behavior was active only in certain habitats and years. Many behavioral phenotypes were neutral and testosterone induced fitness parameters have not been measured in the experiment.
Publication Name: The American Naturalist
Subject: Earth sciences
ISSN: 0003-0147
Year: 1992
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: The effect of nutrients and enriched CO2 environments on production of carbon-based allelochemicals in Plantago: a test of the carbon/nutrient balance hypothesis
- Abstracts: Optimal resource allocation and the marginal value of organs. Physiology and phylogeny: the evolution of locomotor energetics in hylid frogs
- Abstracts: Evolution by sexual selection: what can population comparisons tell us? Sexual selection and imitation: females copy the mate choice of others
- Abstracts: A coevolutionary predator-prey model with quantitative characters. The logic and realism of the hypothesis of exploitation ecosystems