ArticleProceedings. Biological sciences2016
The Trivers-Willard hypothesis: sex ratio or investment?
Article in Proceedings. Biological sciences, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 20 papers.
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Who cites it
20 citing papers in PubMed.
- Trial
- The Relationship of Nest-Site Selection Parameters, Timing of Breeding, Brood Size, and Nestling Body Condition With Brood Sex Ratio in the Black-Crowned Night HeronEcology and evolution · 2026Article
- Crusaders, monks and family fortunes: evolutionary models of male homosexuality and related phenomena.Proceedings. Biological sciences · 2025Article
- Article
- Testing secondary sex ratio bias hypotheses in white-tailed deer in Mississippi, USA.Ecology and evolution · 2024Article
- Sex ratio at birth across 100 years in Sweden and risk of cardiovascular disease and all-cause mortality - a national register study.European journal of epidemiology · 2024Article
- Human milk immune factors, maternal nutritional status, and infant sex: The INSPIRE study.American journal of human biology : the official journal of the Human Biology Council · 2023Article
- Reformulation of Trivers-Willard hypothesis for parental investment.Communications biology · 2022Article
- Girls start life on an uneven playing field: Evidence from lowland rural Nepal.Evolution, medicine, and public health · 2022Article
- Maternal care according to offspring sex and maternal physical condition in mantled howler monkeys (Alouatta palliata).Primates; journal of primatology · 2021Article
- Anthropometrics of Estonian children in relation to family disruption: Thrifty phenotype and Trivers-Willard effects.Evolution, medicine, and public health · 2021Article
- Origins of human milk microbiota: new evidence and arising questions.Gut microbes · 2020Article
- Sex ratios at birth vary with environmental harshness but not maternal condition.Scientific reports · 2019Article
- Different maternal investment strategies for male and female calves in a polygynous mammal.Current zoology · 2019Article
- A split sex ratio in solitary and social nests of a facultatively social bee.Biology letters · 2019Article
- Fathers favour sons, mothers don't discriminate: Sex-biased parental care in northwestern Tanzania.Evolutionary human sciences · 2019Article
- Sexual conflict and the Trivers-Willard hypothesis: Females prefer daughters and males prefer sons.Scientific reports · 2018Article
- Integrating Ecological and Evolutionary Context in the Study of Maternal Stress.Integrative and comparative biology · 2017Article
- Offspring sex preferences among patrilineal and matrilineal Mosuo in Southwest China revealed by differences in parity progression.Royal Society open science · 2016Article
- Parental investment in Tibetan populations does not reflect stated cultural norms.Behavioral ecology : official journal of the International Society for Behavioral EcologyArticle
Corrections and comments
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Authors and funding
3 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The Trivers-Willard hypothesis has commonly been considered to predict two things. First, that a mother in good condition should bias the sex ratio of her offspring towards males (if males exhibit greater variation in reproductive value). Second, that a mother in good condition should invest more per son than per daughter. These two predictions differ empirically, mechanistically and, as we demonstrate here, theoretically too. We construct a simple model of sex allocation that allows simultaneous analysis of both versions of the Trivers-Willard hypothesis. We show that the sex ratio version holds under very general conditions, being valid for a large class of male and female fitness functions. The investment version, on the other hand, is shown to hold only for a small subset of male and female fitness functions. Our results help to make sense of the observation that the sex ratio version is empirically more successful than the investment version.
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