ArticleProceedings. Biological sciences2000
Oestrogen regulates male aggression in the non-breeding season.
Article in Proceedings. Biological sciences, 2000. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 43 papers.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
43 citing papers in PubMed, 210 citations in OpenAlex.
- Timed melatonin administration increases territorial but not non-territorial aggression in female Siberian hamsters.Hormones and behavior · 2026Article
- Dehydroepiandrosterone (DHEA) as a tool for conservation.Environmental monitoring and assessment · 2026Review
- Estrogen profiling in blood and brain: Effects of season and an aggressive interaction in a songbird.PloS one · 2025Article
- Sex, season, age and status influence urinary steroid hormone profiles in an extremely polygynous neotropical bat.Hormones and behavior · 2024Article
- An Aggressive Interaction Rapidly Increases Brain Androgens in a Male Songbird during the Non-breeding Season.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2024Article
- Neuroendocrine mechanisms contributing to the coevolution of sociality and communication.Frontiers in neuroendocrinology · 2023Review
- Brain and circulating steroids in an electric fish: Relevance for non-breeding aggression.PloS one · 2023Article
- Dehydroepiandrosterone (DHEA) increases undirected singing behavior and alters dopaminergic regulation of undirected song in non-breeding male European starlings (Frontiers in endocrinology · 2023Article
- Bidirectional relationships between testosterone and aggression: a critical analysis of four predictions.Integrative and comparative biology · 2022Article
- Electrocommunication signals and aggressive behavior vary among male morphs in an apteronotid fish, Compsaraia samueli.The Journal of experimental biology · 2022Article
- Neuroendocrine patterns underlying seasonal song and year-round territoriality in male black redstarts.Frontiers in zoology · 2021Article
- Neuroendocrine Mechanisms Underlying Non-breeding Aggression: Common Strategies Between Birds and Fish.Frontiers in neural circuits · 2021Review
- Inside the supergene of the bird with four sexes.Hormones and behavior · 2020Review
- Seasonal regulation of behaviour: what role do hormone receptors play?Proceedings. Biological sciences · 2020Article
- A Teleost Fish Model to Understand Hormonal Mechanisms of Non-breeding Territorial Behavior.Frontiers in endocrinology · 2020Review
- Rapid effects of 17β-estradiol on aggressive behavior in songbirds: Environmental and genetic influences.Hormones and behavior · 2018Review
- Rapid effects of estradiol on aggression depend on genotype in a species with an estrogen receptor polymorphism.Hormones and behavior · 2018Article
- UV-filter benzophenone-3 inhibits agonistic behavior in male Siamese fighting fish (Betta splendens).Ecotoxicology (London, England) · 2016Article
- Sex, estradiol, and spatial memory in a food-caching corvid.Hormones and behavior · 2015Article
- Rapid Effects of Estradiol on Aggression in Birds and Mice: The Fast and the Furious.Integrative and comparative biology · 2015Review
Corrections and comments
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Authors and funding
3 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Extensive research has focused on territorial aggression during the breeding season and the roles of circulating testosterone (T) and its conversion to 17beta-oestradiol (E2) in the brain. However, many species also defend territories in the non-breeding season, when circulating T-levels are low. The endocrine control of non-breeding territoriality is poorly understood. The male song sparrow of Washington State is highly territorial year-round, but plasma T is basal in the non-breeding season (autumn and winter). Castration has no effect on aggression in autumn, suggesting that autumnal territoriality is independent of gonadal hormones. However, non-gonadal sex steroids may regulate winter territoriality (e.g. oestrogen synthesis by brain aromatase). In this field experiment, we treated wild non-breeding male song sparrows with a specific aromatase inhibitor (fadrozole, FAD) using micro-osmotic pumps. FAD greatly reduced several aggressive behaviours. The effects of FAD were reversed by E2 replacement. Treatment did not affect body condition or plasma corticosterone, suggesting that all subjects were healthy These data indicate that E2 regulates male aggression in the non-breeding season and challenge the common belief that aggression in the non-breeding season is independent of sex steroids. More generally, these results raise fundamental questions about how sexual and/or aggressive behaviours are maintained in a variety of model vertebrate species despite low circulating levels of sex steroids or despite castration. Such non-classical endocrine mechanisms may be common among vertebrates and play an important role in the regulation of behaviour.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.