Sex roles and sex ratios in animals.
demography
mate choice
parental care
physiology
sex ratios
sex roles
sexual selection
Journal
Biological reviews of the Cambridge Philosophical Society
ISSN: 1469-185X
Titre abrégé: Biol Rev Camb Philos Soc
Pays: England
ID NLM: 0414576
Informations de publication
Date de publication:
04 2023
04 2023
Historique:
revised:
12
10
2022
received:
29
12
2021
accepted:
14
10
2022
pubmed:
30
10
2022
medline:
15
3
2023
entrez:
29
10
2022
Statut:
ppublish
Résumé
In species with separate sexes, females and males often differ in their morphology, physiology and behaviour. Such sex-specific traits are functionally linked to variation in reproductive competition, mate choice and parental care, which have all been linked to sex roles. At the 150th anniversary of Darwin's theory on sexual selection, the question of why patterns of sex roles vary within and across species remains a key topic in behavioural and evolutionary ecology. New theoretical, experimental and comparative evidence suggests that variation in the adult sex ratio (ASR) is a key driver of variation in sex roles. Here, we first define and discuss the historical emergence of the sex role concept, including recent criticisms and rebuttals. Second, we review the various sex ratios with a focus on ASR, and explore its theoretical links to sex roles. Third, we explore the causes, and especially the consequences, of biased ASRs, focusing on the results of correlational and experimental studies of the effect of ASR variation on mate choice, sexual conflict, parental care and mating systems, social behaviour, hormone physiology and fitness. We present evidence that animals in diverse societies are sensitive to variation in local ASR, even on short timescales, and propose explanations for conflicting results. We conclude with an overview of open questions in this field integrating demography, life history and behaviour.
Types de publication
Review
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
462-480Informations de copyright
© 2022 The Authors. Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.
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