Kin selection and sexual conflict shape variation in breastfeeding duration

Kin selection and sexual conflict shape variation in breastfeeding duration | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Kin selection and sexual conflict shape variation in breastfeeding duration Juan Du, Ilaria Pretelli, Min Niu, Yaming Huang, Liqiong Zhou, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4113827/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Breastfeeding provides substantial benefits to infants, yet mothers frequently cease breastfeeding earlier than health guidelines recommend. In cooperative breeding systems, maternal decisions such as the duration of breastfeeding are influenced not only by her own costs and benefits, but also by those of other household members, which are weighed by their relatedness to the child and the parents. We take advantage of variation in post-marital residence patterns among Tibetan communities in southwest China to examine how kinship structure shapes breastfeeding. Analysing feeding histories of 580 children across four residence types (patrilocal, matrilocal, duolocal, and neolocal), we show that average relatedness to co-resident family members is systematically associated with breastfeeding duration. Children and mothers who are more closely related to household members experience longer breastfeeding, while higher paternal relatedness is linked to earlier cessation. These patterns are consistent with conflicts of interest predicted by inclusive fitness theory: parent–offspring conflict and sexual conflict between mothers and fathers. Our findings highlight how family structure within households influences parental investment and cooperation in the family. Biological sciences/Evolution/Anthropology/Biological anthropology Biological sciences/Evolution/Evolutionary theory Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Introduction In humans, successful reproduction and child-rearing typically occur within networks of support, with partners, grandmothers and other family members frequently contributing to cooperative care 1–7 . This dependence is especially pronounced during the crucial early stages of life, when infants are inherently reliant on caregivers for nutrition 8 , of which breast milk is the most important component 9 . Breastfeeding mothers rely on allocare to sustain themselves, care for older children, and maintain household subsistence during this energetically costly period. However, kin influence is not always beneficial to mothers. In some cultures, mothers-in-law or husbands may prioritise high fertility, exposing women to higher reproductive costs 10–15 . Kin selection theory provides a useful framework for understanding how conflicts of interest among family members shape reproductive decision-making, including parent–offspring and sexual conflicts 16–21 . Informed by this framework, we investigate whether the relatedness of mothers, fathers, and children to co-resident family members influences breastfeeding practices in ways consistent with maximising inclusive fitness. Human societies show a diversity of kinship and residence patterns. The choice of residence after marriage—i.e., post-marital residence patterns—significantly influences individuals’ relationships within their households, affecting both kin support and competition 22 . Women often face resource disadvantages in patrilineal societies, and men in matrilineal contexts 23 . These residence patterns shape the sexual division of labour, bargaining power, social networks, and child-rearing practices 24–28 . In this study, we take advantage of the natural variation in household organisation across Tibetan communities, where four distinct post-marital residence patterns—patrilocal, matrilocal, duolocal, and neolocal—structure kinship in contrasting ways. Patrilocal households situate mothers with their husband’s relatives, while in matrilocal households they remain with their own kin. We leverage the variation in genetic relatedness generated by different residence systems as a proxy for bargaining power within households. Under patrilocal residence (where women disperse at marriage and men remain philopatric), mothers are less related to the group than fathers or children. Under matrilocal residence (where men disperse and women are philopatric), the opposite holds: fathers are less related to the household than mothers and children. In duolocal residence, neither men nor women disperse, individuals stay with their kin throughout life. Fathers and mothers thus live apart, and children reside with their mothers. In such households, fathers’ relatedness to the children’s household is very low, mothers’ relatedness is very high, and children’s relatedness lies between the two, as they are surrounded mainly by maternal kin. In neolocal residence, couples establish independent households apart from both natal families. Here, children have high average relatedness to their co-residents because their mother, father, and full siblings are all likely to be present, yielding a mean relatedness close to 0.5. Therefore, depending on household composition, the interests of different family members can have a major impact on breastfeeding duration. We propose two main hypotheses and a composite hypothesis to explain these dynamics. H ypothese 1 Parent–offspring conflict : children benefit from prolonged breastfeeding, whereas parents balance current against future reproduction. Thus, when children are more related to other household members, breastfeeding should be extended, but when parents are more related to other household members, breastfeeding will be shorter. H ypothese 2 Sexual conflict : mothers generally favour longer breastfeeding to maximise child survival and well-being, while fathers gain more from shorter breastfeeding and higher fertility. We would therefore expect maternal and paternal relatedness to predict breastfeeding in opposite directions. Hypothese 3 Both mechanisms: both processes may act together in shaping breastfeeding duration, such that children’s and mothers’ relatedness are associated with longer breastfeeding, and fathers’ relatedness with shorter breastfeeding. In this case, we would expect most of the breastfeeding falls somewhere between the optimum for the mother and the optimum for the father. Note that the correlation between the relatedness of the child with co-resident family members and that of their parents may introduce complexity when testing these hypotheses, see our inferential approach in SI section 2 and 3). In this study, we test these hypotheses using demographic and reproductive histories data of 580 Tibetan children raised under four different residence patterns. This unique variation generates predictable differences in how mothers, fathers, and children are related to other household members, providing a natural experiment for examining how kin selection and sexual conflict ultimately influence breastfeeding decisions, either by providing support that facilitates prolonged breastfeeding or by introducing conflicts that may lead to earlier weaning. Understanding why these patterns matter requires returning to the question of why breastfeeding is significant in the first place. The broad endorsement of breastfeeding by the global healthcare community underscores its significance 29,30 . For infants, breastfeeding acts as a protective shield, reducing mortality from infectious diseases and ensuring better development 31 . For mothers, breastfeeding mitigates the risks of postpartum depression, although it may also contribute to other physical challenges 32–34 . However, while the World Health Organization (WHO) recommends at least six months of exclusive breastfeeding and two years before cessation, actual breastfeeding practices show substantial variation and frequently do not match these recommendations 35–37 . By linking residence patterns, average relatedness, and breastfeeding duration, we ask whether kinship structure shapes the balance of cooperation and conflict in early childcare. In doing so, we place breastfeeding within the broader framework of cooperative breeding, where reproductive decisions emerge not only from mothers 38 but also from the wider set of kin who share the household. Results Cox regression model We employed three Cox regression models to examine predictors of breastfeeding duration. Model 1 looks at the influence of key covariates—mother’s birth cohort, household size, and the child’s sex and birth order. Model 2 assessed the association between post-marital residence patterns and breastfeeding duration, including all control variables from model 1 except household size (which acts as a confounder; see Supplementary Information 3.2). Model 3 examined how the relatedness of children, mothers, and fathers to other household members predicts the timing of breastfeeding termination, while controlling for the same covariates. Our main inferences are drawn from Model 3, which follows a causally principled framework based on Directed Acyclic Graphs (DAGs). To check that these models can distinguish between the three hypotheses considered here, we make use of synthetic-data simulations (see Methods and Supplementary Information 3.3). We further employ a simulation approach to evaluate whether the qualitative direction of effects observed in the empirical data aligns with data generated in silico under parameter sets reflecting the three hypotheses (H1–H3), thereby assessing how plausibly the observed patterns could arise under each scenario. In our control model (Model 1), we found no effect of child sex on breastfeeding duration: sons (LHC = 0.021, 89% PI: −1.098 to 1.146) and daughters (LHC = −0.027, 89% PI: −1.161 to 1.104) were equally likely to be weaned. Maternal birth cohort also had no measurable effect: children of mothers born before 1980 (LHC = 0.043, 89% PI: −0.902 to 0.980), between 1980–1990 (LHC = −0.002, 89% PI: −0.958 to 0.938), and after 1990 (LHC = −0.036, 89% PI: −1.009 to 0.923) were equally likely to cease breastfeeding. Birth order showed no difference between firstborn and later-born children (firstborn LHC = 0.069, 89% PI: −1.099 to 1.215; later-born LHC = −0.071, 89% PI: −1.248 to 1.083). Although birth order is often linked to differential parental investment 39 , this was not observed in our dataset—likely reflecting the characteristics of our sample, which includes mothers giving birth after 2010, a period when compulsory education and family-planning policies had restricted family size (two or three children, depending on region). In contrast, household size showed a strong negative association with breastfeeding duration, with larger household linked to earlier weaning (LHC = 1.197, 89% PI: 0.437–1.959). Model 2 indicated that residence patterns were also associated with variation in breastfeeding duration. Duolocal, matrilocal, and neolocal households were all linked to slightly longer breastfeeding than patrilocal households. Although individual residence effects overlapped zero, the contrasts between patrilocality and each of the other residence types were consistently significant: duolocal (LHC = −0.831, 89% PI: −1.251 to −0.391), matrilocal (LHC = −0.449, 89% PI: −0.801 to −0.098), and neolocal (LHC = −0.550, 89% PI: −0.912 to −0.191). Lower log-hazard coefficients indicate longer breastfeeding durations (Fig. 1; SI Table 2.5), and Figure 2 illustrates the corresponding distribution of breastfeeding lengths across residence patterns. Across different residence patterns, infants and parents varied in their average genetic relatedness to co-resident household members (Fig. 3). In Model 3, although the posterior densities overlap with zero, most of the posterior mass lay consistently on one side, indicating a clear directional trend. Specifically, the proportion of the posterior density that crosses zero is 0.043 for child’s relatedness (≥ 0), 0.101 for mother’s relatedness (≥ 0), and 0.090 for father’s relatedness (≤ 0). These results suggest that the model is reasonably confident about the direction of effects: higher maternal and child relatedness to household members is associated with prolonged breastfeeding, while higher paternal relatedness predicts earlier weaning. Together, these findings point to the joint operation of parent–offspring and sexual conflict in shaping breastfeeding duration (see Fig. 1 and SI Table 4). A similar pattern emerged when comparing the empirical results with simulated data. The synthetic datasets that most closely reproduced the real outcomes were those generated under a combination of positive effects for child and maternal relatedness and a negative effect for paternal relatedness (see SI Table 5.3). As shown in Figure 4, the simulations consistent with these parameter combinations correspond to Hypothesis 3 (H3), indicating that both parent–offspring and sexual conflict jointly shape breastfeeding duration. We further identified the set of generative parameters that produced simulated data most closely matching the empirical results from Model 3. Comparing this “best-fitting” parameter set to our causal hypotheses revealed a consistent pattern: positive coefficients for child and maternal relatedness and a negative coefficient for paternal relatedness (Table 1). This configuration aligns with Hypothesis 3 (H3), supporting the interpretation that both parent–offspring and sexual conflict contribute to shaping breastfeeding duration. Table 1: Descriptive statistics for a distribution of 250 parameter values that generate simulated data best matching the real data (cox model results from the real data are compared to those from 300 simulated datasets, and the generative parameters for the most similar dataset are retained. This process is repeated 300 times to obtain a parameter distribution that can be interpreted in the framework of the hypotheses described above. See supplementary information for more details). Intercept Child Mother Father Mean -0.21 0.97 0.67 -0.59 5% -2.41 0.00 -0.26 -2.60 94% 1.01 4.19 3.39 0.00 Table 2: Reasons given for weaning by 44 women under 3 different residence patterns. Category Neolocal Patrilocal Matrilocal physical costs 3 (19%) 2(14%) 2(14%) opportunity costs 5(31%) 8(57%) 3(21%) social norms 4(25%) 2(14%) 6(43%) Others 4(25%) 2(14%) 3(21%) Self-reported reasons for weaning (Table 2) reveal that behaviours increasing the time and energy demands on women—such as breastfeeding—are often constrained by competing work responsibilities. Breastfeeding is a highly demanding maternal behaviour rather than a simple healthcare practice. Among respondents, opportunity costs—cases where women ceased breastfeeding due to conflicts with work or subsistence labour—were the most frequently cited reason (36%), followed by social norms (27%) and physical difficulties (16%). Although the sample size is limited, notable residence-specific differences emerge: in patrilocal households, opportunity costs were cited most frequently (57%), while in matrilocal households, social norms predominated (43%). These patterns suggest that women’s breastfeeding decisions are influenced by both economic constraints and normative pressures. Some may follow community expectations to avoid social criticism rather than consciously weighing costs and benefits. Across all five regions, household income primarily depends on agricultural or pastoral labour. Accelerometer data from the same population, published elsewhere indicate that women, especially in duolocal and patrilocal systems, engage in significantly more fieldwork and animal husbandry than men 24 , intensifying the trade-off between breastfeeding and economic productivity. While the small sample size limits statistical power, these qualitative findings reinforce that breastfeeding decisions are shaped by labour demands, social expectations, and kinship structure. Discussion Our findings demonstrate that variation in residence patterns predicts breastfeeding duration in ways consistent with both parent–offspring conflict and sexual conflict. Children were breastfed for shorter periods in patrilocal households compared with matrilocal, duolocal, or neolocal households. This pattern supports the idea that the kinship structure of households—by shaping who is related to whom—alters the balance of cooperation and conflict over parental investment. The effects of relatedness were aligned with our theoretical predictions. Higher relatedness of children and mothers to their co-resident kin was associated with prolonged breastfeeding, while higher paternal relatedness predicted earlier weaning. This pattern suggests that children’s and mothers’ inclusive fitness interests are often aligned, and both may conflict with paternal interests 40 . In line with H3, breastfeeding duration appears to be shaped by the combined effects of parent–offspring and sexual conflict, with outcomes typically lying between the maternal and paternal optima. Residence patterns also alter the intensity of conflict. In matrilocal and duolocal households, where mothers remain with their natal kin, maternal bargaining power is greater, and both mother and child are more likely to secure prolonged breastfeeding. In contrast, patrilocal households align fathers more closely with their kin, favouring earlier weaning to increase fertility. These results mirror long-standing predictions from kin selection theory: the distribution of relatedness within households influences who wins reproductive bargaining. An additional explanation for the observed longer breastfeeding duration in matrilocal and duolocal households, as well as the relatively small effect of maternal relatedness, is the reduced parent-offspring conflict between the mother and the child. Matrilineal societies are associated with weaker marriage ties and higher divorce rates as also observed here 41–43 . That means mother's future offspring are, on average, less closely related to the focal child than in patrilineal societies where marriages are more stable. In other words, because the mother gains less reproductive benefit from weaning early when future offspring are more likely to be half-siblings rather than full siblings, her evolutionary incentive to curtail breastfeeding is reduced, even though the child continues to benefit from prolonged nursing. This prediction on weaning conflict goes back to Trivers original formulation of parent-offspring conflict 18 . Bargaining power also differs systematically: women in matrilineal households negotiate reproduction from a position of greater kin support than those in patrilineal households. One important conflict that exists between the breastfeeding mother and other co-resident household members is that her contributions to the family economy reduce while she is breastfeeding. The significant opportunity costs of breastfeeding are further exemplified by findings that breastfeeding mothers often engage in fewer subsistence and domestic tasks than non-breastfeeding women 24,44–46 . Allomaternal care can offset these costs, but its effect depends on the type of support. When kin provide food or labour support, mothers can sustain longer breastfeeding. By contrast, when kin provide direct childcare, opportunity costs may increase, since maternal subsistence work must be combined with frequent separations from the infant 12,47–49 . These proximate dynamics help explain why maternal relatedness had smaller average effects in our models than those of children or fathers. Self-reported reasons for weaning provide additional proximate evidence. Opportunity costs were the most frequently cited reason for stopping breastfeeding, particularly in patrilocal households where women face greater labour demands. Social norms were also cited, especially in matrilocal households, suggesting that maternal behaviour is shaped both by ecological and kinship contexts and by culturally transmitted expectations. While the qualitative sample was small, these reports align closely with the evolutionary patterns identified, and this opens the possibility for future research on the proximate motivations for weaning. Taken together, our results show how inclusive fitness theory can illuminate the dynamics of breastfeeding. Breastfeeding is not solely a maternal choice: it is shaped by kinship structure, bargaining power, and conflicting fitness interests between mothers, fathers, children and other co-resident household members. By linking residence patterns, relatedness, and breastfeeding duration, our study demonstrates that kin selection and sexual conflict together provide a powerful framework for explaining why mothers often cease breastfeeding earlier than health guidelines recommend. Here we show how the family structure, and the relatedness of children and parents to their co-resident household members are shaping breastfeeding duration and it is misleading to interpret reproductive decision-making in the context of mothers alone. Methods Descriptive statistics This study draws on data on 353 female respondents (mothers to 580 children for whom complete information were available for analysis) collected from five regions in western China, each differing in ecology, economy, and culture but sharing a common religion and political administration (Figure 5; SI Tables 2.1 and 3.1). The study sites include two areas in the Gannan Tibetan Autonomous Prefecture of Gansu Province (Zhuoni and Maqu), two in the Garzê Tibetan Autonomous Prefecture of Sichuan Province (Zhaba and Lugu), and one in the Diqing Tibetan Autonomous Prefecture of Yunnan Province (Shangrila). Within each region, data were collected from multiple villages clustered by language, cultural identity, and ecological context (Figure 5). This area is distinctive for the coexistence of four post-marital residence patterns—patrilocal, matrilocal, duolocal, and neolocal—among neighbouring Tibetan communities of farmers and herders. These contrasting kinship systems generate marked variation in the average relatedness of children and parents to their co-resident household members (Figure 3; SI Table 1). The main sources of household income vary across regions. In Maqu, yak and sheep herding provide the principal livelihood, with crops largely reserved for household or livestock consumption 50,51 . The seasonal collection of yartsa gunbu (caterpillar fungus) supplements income but has declined in recent decades 52 . Zhuoni families engage in both barley cultivation and livestock rearing, earning cash income through herding, farming, or temporary wage labour in nearby towns 53 . In Zhaba, Lugu, and Shangrila, most families rely on farming, supplemented by limited herding, foraging for mushrooms and medicinal fungi, or occasional tourism work. Income from wage labour and tourism is irregular and fluctuates annually, and salaried or office-based employment remains rare in all five regions 24,54 . Despite shared Buddhist traditions and other cultural similarities, these Tibetan populations differ in kinship organisation and post-marital residence. Maqu and Zhuoni, inhabited by Amdo Tibetans, follow patrilineal descent and predominantly patrilocal residence 55 . Zhaba and Lugu, in contrast, are matrilineal societies practising duolocal residence 24,56 . Shangrila, located in the Diqing Tibetan Prefecture and inhabited by Kang Tibetans, is characterised by matrilineal descent and matrilocal residence 22 . These regional contrasts provide a unique opportunity to examine how variation in kinship and household composition shapes breastfeeding practices within a single ethnolinguistic population. We conducted household surveys in five regions of western China, walking from one household to another accompanied by local assistants in each area. The survey consisted of two sections: household structure and individual details. For household data, we collected socio-demographic information from the household head or another knowledgeable adult when the head was absent. These data included all co-resident members’ years of birth and marriage, parental identities, dispersal histories, frequency of residence in the household, financial status, and primary subsistence activities. Individual questionnaires were administered separately to adult men and women and recorded marital histories, sibling composition, and reproductive histories. Female respondents provided detailed information on each child’s birth date, delivery method, breastfeeding duration, supplementary feeding practices, and reasons for weaning. Although demographic data were collected for all adult household members, this study focuses on families with children born after 2010 to ensure accurate recall of breastfeeding histories and residence arrangements. This yielded complete breastfeeding data for 580 children (284 daughters and 296 sons; SI Table 2). Breastfeeding cessation was defined as the termination of all suckling and censored at 24 months, because of low reliability of longer reported duration and consistently with the physiological relevance of the behaviour, as per with WHO health recommendations 57 . Households were categorised into four post-marital residence patterns: patrilocal (wives disperse to husbands’ households), matrilocal (husbands disperse to wives’ households), duolocal (neither spouse disperses), and neolocal (both disperse to form new households). Although residence typically corresponds to prevailing descent systems in each region, exceptions occur—for example, matrilocal families within predominantly patrilineal communities. The distribution of residence patterns varied: duolocal residence was most common in Zhaba (53.4%) and present at lower frequencies in Lugu (16.5%), while patrilocality predominated in Zhuoni (63.1%) and Maqu (48.8%). In Shangrila, matrilocality was the dominant pattern (47%) (SI Table 1). Neolocal families exist in all locations (Lugu 35.9%, Maqu 28.9%, Shangrila 16.9%, Zhaba 16.8%, Zhuoni 16.9%). To complement the quantitative analysis and gain insight into proximate motivations for weaning, we conducted semi-structured interviews with 44 women in Shangrila. Participants were asked to describe their reasons for stopping breastfeeding, which we subsequently classified into four categories: physical costs, social norms, opportunity costs, and other reasons (Table 2; see SI Table 3 for detailed responses). Causal model The comparison of hypotheses in this study is complicated by potential equifinality—that is, different hypotheses, described as causal models, can produce similar patterns in the data, making them difficult to distinguish empirically. This issue arises because of the mechanism of genetic inheritance, which correlates the relatedness of children and parents to other household members. Consequently, it becomes challenging to disentangle whether observed effects are driven primarily by the parent’s relatedness, the child’s relatedness, or both (see Supplementary Information, Section 2, for a detailed discussion of the implications for causal inference). To address these complexities and the non-mutually exclusive nature of our hypotheses, we employ a multi-method approach combining causally validated Cox regression models with comparisons between synthetic datasets (see Supplementary Information, Section 5) and empirical data on household demographics and breastfeeding durations collected in 2016–2017. First, we use a principled causal framework to guide both model specification and interpretation. Specifically, we employ Directed Acyclic Graphs (DAGs) to clarify the assumed relationships among variables and define the appropriate adjustment set for inference. Figure 7 illustrates the variables included in our analysis. As our main goal is to estimate the direct effects of the mother’s, father’s, and child’s average relatedness on breastfeeding duration (tested in Model 3), the key predictors include these three variables, along with village to account for cultural and ecological variation. We additionally control for household size, and for maternal birth cohort, child sex, and birth order to improve estimate precision. All variables are described in detail in Supplementary Information, Section 3.1. Statistical analysis We used Cox proportional-hazards regressions to test which variables were associated with the termination of breastfeeding, treating the process as a survival analysis where predictors—such as relatedness of individual relatedness and other covariates—affects the risk of breastfeeding cessation. This approach also accommodates censoring, accounting for children who were still breastfed at the time of the interview; Breastfeeding durations exceeding 24 months were censored due to both the lower reliability of maternal recall and the reduced physiological relevance of breastfeeding beyond this period for mother and child (see SI Figure 2 for complete data distribution). Control variables included the mother’s birth cohort, child’s birth order and sex, and household size (except in Model 2, where household size lies on the causal path of residence type). Mothers’ birth cohorts were grouped in ten-year intervals (≤1980, 1980–1989, ≥1990). Because some mothers contributed more than one child to the dataset, maternal ID was included as a random effect, along with village, to control for ecological and cultural clustering. Household size was entered as an ordinal, monotonically increasing predictor. Household size varied across residence patterns (duolocal: 7.77 ± 2.92; neolocal: 5.50 ± 1.40; patrilocal: 6.83 ± 1.90; matrilocal: 6.78 ± 1.92). Average genetic relatedness for each individual (child, mother and father) to their co-resident household members was calculated using the Kinship2 package (version 1.9.6) based on pedigree data, following standard formulations from Hamilton (1964). Bayesian Cox models were implemented in Stan with weakly regularizing priors (details in SI section 4). Models were run using the CmdStan package (version 0.5.3) for 3,000 iterations after 1,000 warm-up iterations. Model convergence was verified by R̂ ≈ 1 and large effective sample sizes. Plots were generated using the ggplot2, contsurvplot, rnaturalearth, and ggspatial packages. All analyses were performed in R (version 4.2.2). Data and reproducible code are available at: https://github.com/lalla-ilaria/breastfeeding_relatedness. Ethical clearance was obtained from University College London and Lanzhou University. Simulations addressing risk of equifinality Additionally, we conducted further analyses to account for the fact that children and their parents share, on average, half of their genomes. This biological reality creates a correlation between the average relatedness of children and that of their parents to other household members, introducing the potential for equifinality—the risk that different causal hypotheses could generate similar observable patterns. To address this, we generated multiple simulated datasets of breastfeeding duration under each hypothesis (H1–H3) and compared the results of Model 3—which includes predictors for the relatedness of children, mothers, and fathers—when fitted to both real and simulated data (Figure 4). We also repeated this comparison using alternative Cox models that included different combinations of relatedness predictors (e.g., only one at a time or pairwise combinations) to evaluate their ability to discriminate among hypotheses (see Supplementary Figure 6). Model 3, which incorporates all three relatedness variables alongside the control covariates, provided an accurate performance in distinguishing among the hypothesised mechanisms and mitigating equifinality (see Supplementary Information, Section 3.3). This approach using simulations is particularly advantageous because, unlike fully parametric models, Cox regressions do not specify a complete likelihood for event times, precluding standard posterior predictive checks for model validation. 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Du, J. & Mace, R. Marriage stability in a pastoralist society. Behav. Ecol. 30, 1567–1574 (2019). Batan, M., Li, R. & Scanlon, K. Association of child care providers’ breastfeeding support with breastfeeding duration at 6 months. Matern. Child Health J. 17, 708–713 (2013). Hawkes, K., O’Connell, J. F. & Blurton Jones, N. G. Hadza women’s time allocation, offspring provisioning, and the evolution of long postmenopausal life spans. Curr. Anthropol. 38, 551–577 (1997). Quinlan, R. J. & Quinlan, M. B. Human lactation, pair-bonds, and alloparents: a cross-cultural analysis. Hum. Nat. 19, 87–102 (2008). Emmott, E. Improving Breastfeeding Rates: Evolutionary Anthropological Insights for Public Health (Cambridge Univ. Press, 2023). Emmott, E. H., Page, A. E. & Myers, S. Typologies of postnatal support and breastfeeding at two months in the UK. Soc. Sci. Med. 246, 112790 (2020). Myers, S., Page, A. E. & Emmott, E. H. The differential role of practical and emotional support in infant feeding experience in the UK. Philos. Trans. R. Soc. B 376, 20200021 (2021). Du, J. & Mace, R. Parental investment in Tibetan populations does not reflect stated cultural norms. Behav. Ecol. 29, 106–116 (2018). Gelek, L. Anthropological field survey on basic education development in the Tibetan nomadic community of Maqu, Gansu, China. Asian Ethn. 7, 103–109 (2006). Xing, H.Y. & Wang, X. Interembedding and integration: the construction of ethnic communities in economic interactions—an investigation based on the cordyceps trade in the northwestern tibetan region. J. Shanghai Inst. Socialism 2023, 60–75 (2023). Zhou, L. et al. Monks relax sibling competition over parental resources in Tibetan populations. Behav. Ecol. 33, 1070–1079 (2022). Huang, Y., Bai, P., Zhou, L., Mace, R. & Du, J. A rapid decline in gender bias relates to changes in subsistence practices over demographic changes in a formerly matrilineal community. iScience 28, (2025). Zou, Z. Monk’s System in Tibetan Buddhist temple and ecological environment in Tibetan areas: view of the South Gansu Tibetan Area during the period of the republic of China . MA thesis, Shanxi Normal Univ. (2006). Jiao, H. & Zhong, Z. Survey and Research Summary of Tibetan Literature and History in Zhaba . (Southwest Jiaotong Univ. Press, 2017). World Health Organization. Exclusive Breastfeeding for Optimal Growth, Development and Health of Infants (World Health Organization, 2023). Hamilton, W. D. The genetical evolution of social behaviour. II. J. Theor. Biol. 7, 17–52 (1964). Wright, S. Coefficients of inbreeding and relationship. Am. Nat. 56, 330–338 (1922). Additional Declarations There is NO Competing Interest. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-4113827","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":559293180,"identity":"cddec654-5b3e-4eb8-8a98-9be41039a66b","order_by":0,"name":"Juan Du","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3UlEQVRIiWNgGAWjYBACxgYQyQZE/M0HGBgKwILMxGnhkziWwMBgQIQWCABqkWPIMSBOC/OM5GcPGMoOA3Wd+Sbxw4BBnr+Bx9gAr8NmpJkbMJwDamHu3SbZY8BgOOMAj3ECfi0JZhKMbSBbzm6TBjqMcQMDj/EB/FrSv0G15DwDabEnQksOzJYcNpCWRJAW/A7reVMmkXAunYdN4pixZY+BRPKMw2zFeL1v2J6+TeJDmbWcfH/zwxs/Kmxs+9ubN0vg1dIAJIDu4IHyJQhHpDwB+VEwCkbBKBgFDAwAO447Kb8X7eEAAAAASUVORK5CYII=","orcid":"","institution":"State Key Laboratory of Grassland and Agro-Ecosystems","correspondingAuthor":true,"prefix":"","firstName":"Juan","middleName":"","lastName":"Du","suffix":""},{"id":559293181,"identity":"9941dc6d-1fa9-48d1-bb4f-89f1f2797d07","order_by":1,"name":"Ilaria Pretelli","email":"","orcid":"https://orcid.org/0000-0002-8244-5737","institution":"Institute for Advanced Study in Toulouse","correspondingAuthor":false,"prefix":"","firstName":"Ilaria","middleName":"","lastName":"Pretelli","suffix":""},{"id":559293182,"identity":"292e0713-0bda-47d6-9df9-3e2082db97e5","order_by":2,"name":"Min Niu","email":"","orcid":"","institution":"College of Ecology","correspondingAuthor":false,"prefix":"","firstName":"Min","middleName":"","lastName":"Niu","suffix":""},{"id":559293183,"identity":"b52f4da0-478c-4dde-b293-556a1dea8e6d","order_by":3,"name":"Yaming Huang","email":"","orcid":"https://orcid.org/0009-0004-0372-9515","institution":"College of Ecology","correspondingAuthor":false,"prefix":"","firstName":"Yaming","middleName":"","lastName":"Huang","suffix":""},{"id":559293184,"identity":"3b37f966-b747-4d7f-ba86-89b816d5fba5","order_by":4,"name":"Liqiong Zhou","email":"","orcid":"","institution":"College of Ecology","correspondingAuthor":false,"prefix":"","firstName":"Liqiong","middleName":"","lastName":"Zhou","suffix":""},{"id":559293185,"identity":"e471552e-8987-4a18-bcf6-70311a9cbc77","order_by":5,"name":"Yuan Chen","email":"","orcid":"https://orcid.org/0000-0002-7069-1631","institution":"University College London","correspondingAuthor":false,"prefix":"","firstName":"Yuan","middleName":"","lastName":"Chen","suffix":""},{"id":559293186,"identity":"61148f1c-92e7-4e4f-bf4c-741f181de92f","order_by":6,"name":"Ruth Mace","email":"","orcid":"https://orcid.org/0000-0002-6137-7739","institution":"University College London","correspondingAuthor":false,"prefix":"","firstName":"Ruth","middleName":"","lastName":"Mace","suffix":""}],"badges":[],"createdAt":"2024-03-16 15:30:24","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4113827/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4113827/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":98429776,"identity":"d01cf307-a752-4bc5-afa3-8857536fb43f","added_by":"auto","created_at":"2025-12-17 16:44:07","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":50389,"visible":true,"origin":"","legend":"\u003cp\u003ePosterior log-hazard coefficient estimates for the relevant predictors. Negative coefficient estimates indicate longer breastfeeding duration (lower risk of breastfeeding termination), whereas positive coefficients indicate shorter duration (higher risk of breastfeeding termination). Black points represent results from Model 1, blue from Model 2, and red from Model 3. Coefficients for patrilocality differ significantly from the other residence strategies, even though the effect of each specific residence pattern on breastfeeding duration overlaps with zero. Differences between strategies are as follows: duolocal vs. patrilocal = −0.831 (−1.251 to −0.391), matrilocal vs. patrilocal = −0.449 (−0.801 to −0.098), and neolocal vs. patrilocal = −0.550 (−0.912 to −0.191). All values refer to the posterior means and 89% credible intervals.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4113827/v1/83fa4ac8a45d2938d78a1c1d.png"},{"id":98429756,"identity":"1d2e167e-d86b-472c-ba06-0679208a17ec","added_by":"auto","created_at":"2025-12-17 16:44:06","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":50591,"visible":true,"origin":"","legend":"\u003cp\u003eDensity plots of individual children’s breastfeeding duration under different residence patterns. Colours indicate residence type (yellow = patrilocal; red = duolocal; blue = matrilocal; green = neolocal). Vertical lines represent mean breastfeeding duration for each residence pattern (solid = duolocal; dashed = patrilocal; dotted = matrilocal; dot–dash = neolocal).\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-4113827/v1/f2aa428110b359a256767667.png"},{"id":98072482,"identity":"66aa444e-f8f8-4f3c-ac8c-9f50b1d40372","added_by":"auto","created_at":"2025-12-12 13:13:38","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":103350,"visible":true,"origin":"","legend":"\u003cp\u003eDensity plots of individuals’ average relatedness to other household members under different post-marital residence patterns. Colours indicate family members (blue = father; red = mother; green = child). Lines represent mean relatedness for each individual type (solid = mother; dashed = father; dotted = child).\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-4113827/v1/b8e28817e68b5671ca78bba9.png"},{"id":98429114,"identity":"8f0291b2-062c-4bd0-84f3-b90bee7f3634","added_by":"auto","created_at":"2025-12-17 16:42:48","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":28144,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of log-hazard coefficients from Cox regression Model 3 fitted on the real dataset (light-coloured squares; N = 580) and on 50 simulated datasets (darker circles) generated under different hypotheses (H1–H3). Colours indicate the predictors: green = child’s relatedness effect, red = mother’s relatedness effect, and blue = father’s relatedness effect. Simulations show that the pattern most consistent with the empirical data corresponds to H3, reflecting combined parent–offspring and sexual conflict.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-4113827/v1/6dcf57271532c41e48497c01.png"},{"id":98072488,"identity":"45c79079-3ed4-4ac7-99c4-46f4c14023e2","added_by":"auto","created_at":"2025-12-12 13:13:38","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":244730,"visible":true,"origin":"","legend":"\u003cp\u003eMap of the study sites. 5 different regions were indicated on the map with red dots, note that in each region, there are different villages where we collected data. The border was shown based on the provincial level in China.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-4113827/v1/3e6c396a883c931eddea8499.png"},{"id":98428633,"identity":"eda65d3e-c64c-4112-a76a-cbc36e78e16f","added_by":"auto","created_at":"2025-12-17 16:42:12","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":67485,"visible":true,"origin":"","legend":"\u003cp\u003eExamples of pedigrees illustrating each post-marital residence pattern. Circles represent females and squares represent males. Barred symbols indicate individuals present in the genealogical dataset but not co-residing in the household (e.g., deceased members or non-resident fathers). For each individual, average relatedness is calculated by summing genealogical relatedness to all other household members and dividing by the number of co-resident individuals (excluding the focal individual)\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-4113827/v1/058c786b71b1165114df21be.png"},{"id":98429582,"identity":"662424c5-b28f-4821-bd15-6ca17ff87889","added_by":"auto","created_at":"2025-12-17 16:43:46","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":59629,"visible":true,"origin":"","legend":"\u003cp\u003eDirected acyclic graph (DAG) showing the relationships among variables influencing breastfeeding duration. Some relevant variables—such as physical constraints and household wealth—were not available in the dataset. The effects of these, along with other unmeasured variables (indicated by the circled Us), are likely captured by the random effects for individual mothers. We do not assume that residence patterns directly affect breastfeeding duration; rather, we propose that geographical location (village), representing cultural and ecological variation, influences both residence patterns and breastfeeding duration.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-4113827/v1/00ee7fda0046254c5575877c.png"},{"id":98622893,"identity":"70ba0e45-9d67-43f1-91c6-b10c28bcff14","added_by":"auto","created_at":"2025-12-19 17:03:24","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1019538,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4113827/v1/6067ac68-3bb5-4cea-9bf6-e319ff96ce4f.pdf"},{"id":98429024,"identity":"061e05e0-fee4-48ac-b692-423be772e4b1","added_by":"auto","created_at":"2025-12-17 16:42:42","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":194320,"visible":true,"origin":"","legend":"Supplementary Information","description":"","filename":"SupplementaryInformation.docx","url":"https://assets-eu.researchsquare.com/files/rs-4113827/v1/9f8be68379b46c8329c3bc5d.docx"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Kin selection and sexual conflict shape variation in breastfeeding duration","fulltext":[{"header":"Introduction ","content":"\u003cp\u003eIn humans, successful reproduction and child-rearing typically occur within networks of support, with partners, grandmothers and other family members frequently contributing to cooperative care\u003csup\u003e1\u0026ndash;7\u003c/sup\u003e. This dependence is especially pronounced during the crucial early stages of life, when infants are inherently reliant on caregivers for nutrition\u003csup\u003e8\u003c/sup\u003e, of which breast milk is the most important component\u003csup\u003e9\u003c/sup\u003e. Breastfeeding mothers rely on allocare to sustain themselves, care for older children, and maintain household subsistence during this energetically costly period. However, kin influence is not always beneficial to mothers. In some cultures, mothers-in-law or husbands may prioritise high fertility, exposing women to higher reproductive costs\u003csup\u003e10\u0026ndash;15\u003c/sup\u003e. \u0026nbsp; Kin selection theory provides a useful framework for understanding how conflicts of interest among family members shape reproductive decision-making, including parent\u0026ndash;offspring and sexual conflicts\u003csup\u003e16\u0026ndash;21\u003c/sup\u003e. Informed by this framework, we investigate whether the relatedness of mothers, fathers, and children to co-resident family members influences breastfeeding practices in ways consistent with maximising inclusive fitness.\u003c/p\u003e\n\u003cp\u003eHuman societies show a diversity of kinship and residence patterns. The choice of residence after marriage\u0026mdash;i.e., post-marital residence patterns\u0026mdash;significantly influences individuals\u0026rsquo; relationships within their households, affecting both kin support and competition\u003csup\u003e22\u003c/sup\u003e. Women often face resource disadvantages in patrilineal societies, and men in matrilineal contexts\u003csup\u003e23\u003c/sup\u003e. These residence patterns shape the sexual division of labour, bargaining power, social networks, and child-rearing practices \u003csup\u003e24\u0026ndash;28\u003c/sup\u003e. In this study, we take advantage of the natural variation in household organisation across Tibetan communities, where four distinct post-marital residence patterns\u0026mdash;patrilocal, matrilocal, duolocal, and neolocal\u0026mdash;structure kinship in contrasting ways. Patrilocal households situate mothers with their husband\u0026rsquo;s relatives, while in matrilocal households they remain with their own kin. We leverage the variation in genetic relatedness generated by different residence systems as a proxy for bargaining power within households. Under patrilocal residence (where women disperse at marriage and men remain philopatric), mothers are less related to the group than fathers or children. Under matrilocal residence (where men disperse and women are philopatric), the opposite holds: fathers are less related to the household than mothers and children. In duolocal residence, neither men nor women disperse, individuals stay with their kin throughout life. Fathers and mothers thus live apart, and children reside with their mothers. In such households, fathers\u0026rsquo; relatedness to the children\u0026rsquo;s household is very low, mothers\u0026rsquo; relatedness is very high, and children\u0026rsquo;s relatedness lies between the two, as they are surrounded mainly by maternal kin. In neolocal residence, couples establish independent households apart from both natal families. Here, children have high average relatedness to their co-residents because their mother, father, and full siblings are all likely to be present, yielding a mean relatedness close to 0.5.\u003c/p\u003e\n\u003cp\u003eTherefore, depending on household composition, the interests of different family members can have a major impact on breastfeeding duration. We propose two main hypotheses and a composite hypothesis to explain these dynamics.\u003c/p\u003e\n\u003cul\u003e\n \u003cli\u003e\u003cem\u003eH\u003c/em\u003e\u003cem\u003eypothese\u0026nbsp;\u003c/em\u003e\u003cem\u003e1\u003c/em\u003e\u003cem\u003eParent\u0026ndash;offspring conflict\u003c/em\u003e\u003cem\u003e:\u0026nbsp;\u003c/em\u003echildren benefit from prolonged breastfeeding, whereas parents balance current against future reproduction. Thus, when children are more related to other household members, breastfeeding should be extended, but when parents are more related to other household members, breastfeeding will be shorter.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003e\u003cem\u003eH\u003c/em\u003e\u003cem\u003eypothese 2 \u0026nbsp;\u003c/em\u003e\u003cem\u003eSexual conflict\u003c/em\u003e\u003cem\u003e:\u0026nbsp;\u003c/em\u003emothers generally favour longer breastfeeding to maximise child survival and well-being, while fathers gain more from shorter breastfeeding and higher fertility. We would therefore expect maternal and paternal relatedness to predict breastfeeding in opposite directions.\u003c/li\u003e\n \u003cli\u003e\u003cem\u003eHypothese 3 \u0026nbsp;Both mechanisms:\u0026nbsp;\u003c/em\u003eboth processes may act together in shaping breastfeeding duration, such that children\u0026rsquo;s and mothers\u0026rsquo; relatedness are associated with longer breastfeeding, and fathers\u0026rsquo; relatedness with shorter breastfeeding. In this case, we would expect most of the breastfeeding falls somewhere between the optimum for the mother and the optimum for the father. \u0026nbsp;Note that the correlation between the relatedness of the child with co-resident family members and that of their parents may introduce complexity when testing these hypotheses, see our inferential approach in SI section 2 and 3).\u0026nbsp;\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eIn this study, we test these hypotheses using demographic and reproductive histories data of 580 Tibetan children raised under four different residence patterns. This unique variation generates predictable differences in how mothers, fathers, and children are related to other household members, providing a natural experiment for examining how kin selection and sexual conflict\u0026nbsp;ultimately influence breastfeeding decisions,\u0026nbsp;either by providing support that facilitates prolonged breastfeeding or by introducing conflicts that may lead to earlier weaning.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eUnderstanding why these patterns matter requires returning to the question of why breastfeeding is significant in the first place. The broad endorsement of breastfeeding by the global healthcare community underscores its significance\u003csup\u003e29,30\u003c/sup\u003e. For infants, breastfeeding acts as a protective shield, reducing mortality from infectious diseases and ensuring better development\u003csup\u003e31\u003c/sup\u003e. For mothers, breastfeeding mitigates the risks of postpartum depression, although it may also contribute to other physical challenges\u003csup\u003e32\u0026ndash;34\u003c/sup\u003e. However, while the World Health Organization (WHO) recommends at least six months of exclusive breastfeeding and two years before cessation, actual breastfeeding practices show substantial variation and frequently do not match these recommendations \u003csup\u003e35\u0026ndash;37\u003c/sup\u003e. \u0026nbsp; By linking residence patterns, average relatedness, and breastfeeding duration, we ask whether kinship structure shapes the balance of cooperation and conflict in early childcare. In doing so, we place breastfeeding within the broader framework of cooperative breeding, where reproductive decisions emerge not only from mothers \u003csup\u003e38\u003c/sup\u003e but also from the wider set of kin who share the household.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eCox regression model\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe employed three Cox regression models to examine predictors of breastfeeding duration. Model 1 looks at the influence of key covariates\u0026mdash;mother\u0026rsquo;s birth cohort, household size, and the child\u0026rsquo;s sex and birth order. Model 2 assessed the association between post-marital residence patterns and breastfeeding duration, including all control variables from model 1 except household size (which acts as a confounder; see Supplementary Information 3.2). Model 3 examined how the relatedness of children, mothers, and fathers to other household members predicts the timing of breastfeeding termination, while controlling for the same covariates. Our main inferences are drawn from Model 3, which follows a causally principled framework based on Directed Acyclic Graphs (DAGs). To check that these models can distinguish between the three hypotheses considered here, we make use of synthetic-data simulations (see Methods and Supplementary Information 3.3). We further employ a simulation approach to evaluate whether the qualitative direction of effects observed in the empirical data aligns with data generated in silico under parameter sets reflecting the three hypotheses (H1\u0026ndash;H3), thereby assessing how plausibly the observed patterns could arise under each scenario.\u003c/p\u003e\n\u003cp\u003eIn our control model (Model 1), we found no effect of child sex on breastfeeding duration: sons (LHC = 0.021, 89% PI:\u0026nbsp;\u0026minus;1.098 to 1.146) and daughters (LHC =\u0026nbsp;\u0026minus;0.027, 89% PI:\u0026nbsp;\u0026minus;1.161 to 1.104) were equally likely to be weaned. Maternal birth cohort also had no measurable effect: children of mothers born before 1980 (LHC = 0.043, 89% PI:\u0026nbsp;\u0026minus;0.902 to 0.980), between 1980\u0026ndash;1990 (LHC =\u0026nbsp;\u0026minus;0.002, 89% PI:\u0026nbsp;\u0026minus;0.958 to 0.938), and after 1990 (LHC =\u0026nbsp;\u0026minus;0.036, 89% PI:\u0026nbsp;\u0026minus;1.009 to 0.923) were equally likely to cease breastfeeding. Birth order showed no difference between firstborn and later-born children (firstborn LHC = 0.069, 89% PI:\u0026nbsp;\u0026minus;1.099 to 1.215; later-born LHC =\u0026nbsp;\u0026minus;0.071, 89% PI:\u0026nbsp;\u0026minus;1.248 to 1.083). Although birth order is often linked to differential parental investment \u003csup\u003e39\u003c/sup\u003e, this was not observed in our dataset\u0026mdash;likely reflecting the characteristics of our sample, which includes mothers giving birth after 2010, a period when compulsory education and family-planning policies had restricted family size (two or three children, depending on region). In contrast, household size showed a strong negative association with breastfeeding duration, with larger household linked to earlier weaning (LHC = 1.197, 89% PI: 0.437\u0026ndash;1.959).\u003c/p\u003e\n\u003cp\u003eModel 2 indicated that residence patterns were also associated with variation in breastfeeding duration. Duolocal, matrilocal, and neolocal households were all linked to slightly longer breastfeeding than patrilocal households. Although individual residence effects overlapped zero, the contrasts between patrilocality and each of the other residence types were consistently significant: duolocal (LHC = \u0026minus;0.831, 89% PI: \u0026minus;1.251 to \u0026minus;0.391), matrilocal (LHC = \u0026minus;0.449, 89% PI: \u0026minus;0.801 to \u0026minus;0.098), and neolocal (LHC = \u0026minus;0.550, 89% PI: \u0026minus;0.912 to \u0026minus;0.191). Lower log-hazard coefficients indicate longer breastfeeding durations (Fig. 1; SI Table 2.5), and Figure 2 illustrates the corresponding distribution of breastfeeding lengths across residence patterns.\u003c/p\u003e\n\u003cp\u003eAcross different residence patterns, infants and parents varied in their average genetic relatedness to co-resident household members (Fig. 3). In Model 3, although the posterior densities overlap with zero, most of the posterior mass lay consistently on one side, indicating a clear directional trend. Specifically, the proportion of the posterior density that crosses zero is 0.043 for child\u0026rsquo;s relatedness (\u0026ge; 0), 0.101 for mother\u0026rsquo;s relatedness (\u0026ge; 0), and 0.090 for father\u0026rsquo;s relatedness (\u0026le; 0). These results suggest that the model is reasonably confident about the direction of effects: higher maternal and child relatedness to household members is associated with prolonged breastfeeding, while higher paternal relatedness predicts earlier weaning. Together, these findings point to the joint operation of parent\u0026ndash;offspring and sexual conflict in shaping breastfeeding duration (see Fig. 1 and SI Table 4).\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;A similar pattern emerged when comparing the empirical results with simulated data. The synthetic datasets that most closely reproduced the real outcomes were those generated under a combination of positive effects for child and maternal relatedness and a negative effect for paternal relatedness (see SI Table 5.3). As shown in Figure 4, the simulations consistent with these parameter combinations correspond to Hypothesis 3 (H3), indicating that both parent\u0026ndash;offspring and sexual conflict jointly shape breastfeeding duration.\u003c/p\u003e\n\u003cp\u003eWe further identified the set of generative parameters that produced simulated data most closely matching the empirical results from Model 3. Comparing this \u0026ldquo;best-fitting\u0026rdquo; parameter set to our causal hypotheses revealed a consistent pattern: positive coefficients for child and maternal relatedness and a negative coefficient for paternal relatedness (Table 1). This configuration aligns with Hypothesis 3 (H3), supporting the interpretation that both parent\u0026ndash;offspring and sexual conflict contribute to shaping breastfeeding duration.\u003c/p\u003e\n\u003cp\u003eTable 1: Descriptive statistics for a distribution of 250 parameter values that generate simulated data best matching the real data (cox model results from the real data are compared to those from 300 simulated datasets, and the generative parameters for the most similar dataset are retained. This process is repeated 300 times to obtain a parameter distribution that can be interpreted in the framework of the hypotheses described above. See supplementary information for more details).\u003c/p\u003e\n\u003cdiv align=\"Left\"\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"409\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 81px;\"\u003e\n \u003cp\u003eIntercept\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003eChild\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 77px;\"\u003e\n \u003cp\u003eMother\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003eFather\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003eMean\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 81px;\"\u003e\n \u003cp\u003e-0.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 77px;\"\u003e\n \u003cp\u003e0.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e-0.59\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003e5%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 81px;\"\u003e\n \u003cp\u003e-2.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 77px;\"\u003e\n \u003cp\u003e-0.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e-2.60\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 117px;\"\u003e\n \u003cp\u003e94%\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 81px;\"\u003e\n \u003cp\u003e1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 66px;\"\u003e\n \u003cp\u003e4.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 77px;\"\u003e\n \u003cp\u003e3.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 68px;\"\u003e\n \u003cp\u003e0.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTable 2: Reasons given for weaning by 44 women under 3 different residence patterns.\u003c/p\u003e\n\u003cdiv align=\"Left\"\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"415\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 127px;\"\u003e\n \u003cp\u003eCategory\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 86px;\"\u003e\n \u003cp\u003eNeolocal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 81px;\"\u003e\n \u003cp\u003ePatrilocal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 121px;\"\u003e\n \u003cp\u003eMatrilocal\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 127px;\"\u003e\n \u003cp\u003ephysical costs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 86px;\"\u003e\n \u003cp\u003e3 (19%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 81px;\"\u003e\n \u003cp\u003e2(14%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 121px;\"\u003e\n \u003cp\u003e2(14%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 127px;\"\u003e\n \u003cp\u003eopportunity costs\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 86px;\"\u003e\n \u003cp\u003e5(31%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 81px;\"\u003e\n \u003cp\u003e8(57%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 121px;\"\u003e\n \u003cp\u003e3(21%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 127px;\"\u003e\n \u003cp\u003esocial norms\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 86px;\"\u003e\n \u003cp\u003e4(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 81px;\"\u003e\n \u003cp\u003e2(14%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 121px;\"\u003e\n \u003cp\u003e6(43%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"bottom\" style=\"width: 127px;\"\u003e\n \u003cp\u003eOthers\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 86px;\"\u003e\n \u003cp\u003e4(25%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 81px;\"\u003e\n \u003cp\u003e2(14%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"bottom\" style=\"width: 121px;\"\u003e\n \u003cp\u003e3(21%)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eSelf-reported reasons for weaning (Table 2) reveal that behaviours increasing the time and energy demands on women\u0026mdash;such as breastfeeding\u0026mdash;are often constrained by competing work responsibilities. Breastfeeding is a highly demanding maternal behaviour rather than a simple healthcare practice. Among respondents, opportunity costs\u0026mdash;cases where women ceased breastfeeding due to conflicts with work or subsistence labour\u0026mdash;were the most frequently cited reason (36%), followed by social norms (27%) and physical difficulties (16%). Although the sample size is limited, notable residence-specific differences emerge: in patrilocal households, opportunity costs were cited most frequently (57%), while in matrilocal households, social norms predominated (43%). These patterns suggest that women\u0026rsquo;s breastfeeding decisions are influenced by both economic constraints and normative pressures. Some may follow community expectations to avoid social criticism rather than consciously weighing costs and benefits.\u003c/p\u003e\n\u003cp\u003eAcross all five regions, household income primarily depends on agricultural or pastoral labour. Accelerometer data from the same population, published elsewhere indicate that women, especially in duolocal and patrilocal systems, engage in significantly more fieldwork and animal husbandry than men\u003csup\u003e24\u003c/sup\u003e, intensifying the trade-off between breastfeeding and economic productivity. While the small sample size limits statistical power, these qualitative findings reinforce that breastfeeding decisions are shaped by labour demands, social expectations, and kinship structure.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eOur findings demonstrate that variation in residence patterns predicts breastfeeding duration in ways consistent with both parent–offspring conflict and sexual conflict. Children were breastfed for shorter periods in patrilocal households compared with matrilocal, duolocal, or neolocal households. This pattern supports the idea that the kinship structure of households—by shaping who is related to whom—alters the balance of cooperation and conflict over parental investment.\u003c/p\u003e\n\u003cp\u003eThe effects of relatedness were aligned with our theoretical predictions. Higher relatedness of children and mothers to their co-resident kin was associated with prolonged breastfeeding, while higher paternal relatedness predicted earlier weaning. This pattern suggests that children’s and mothers’ inclusive fitness interests are often aligned, and both may conflict with paternal interests\u003csup\u003e40\u003c/sup\u003e. In line with H3, breastfeeding duration appears to be shaped by the combined effects of parent–offspring and sexual conflict, with outcomes typically lying between the maternal and paternal optima.\u003c/p\u003e\n\u003cp\u003eResidence patterns also alter the intensity of conflict. In matrilocal and duolocal households, where mothers remain with their natal kin, maternal bargaining power is greater, and both mother and child are more likely to secure prolonged breastfeeding. In contrast, patrilocal households align fathers more closely with their kin, favouring earlier weaning to increase fertility. These results mirror long-standing predictions from kin selection theory: the distribution of relatedness within households influences who wins reproductive bargaining.\u003c/p\u003e\n\u003cp\u003eAn additional explanation for the observed longer breastfeeding duration in matrilocal and duolocal households, as well as the relatively small effect of maternal relatedness, is the reduced parent-offspring conflict between the mother and the child. \u0026nbsp;Matrilineal societies are associated with weaker marriage ties and higher divorce rates as also observed here \u003csup\u003e41–43\u003c/sup\u003e. \u0026nbsp; That means mother's future offspring are, on average, less closely related to the focal child than in patrilineal societies where marriages are more stable. In other words, because the mother gains less reproductive benefit from weaning early when future offspring are more likely to be half-siblings rather than full siblings, her evolutionary incentive to curtail breastfeeding is reduced, even though the child continues to benefit from prolonged nursing. \u0026nbsp;This prediction on weaning conflict goes back to Trivers original formulation of parent-offspring conflict \u003csup\u003e18\u003c/sup\u003e. \u0026nbsp; \u0026nbsp;Bargaining power also differs systematically: women in matrilineal households negotiate reproduction from a position of greater kin support than those in patrilineal households.\u003c/p\u003e\n\u003cp\u003eOne important conflict that exists between the breastfeeding mother and other co-resident household members is that her contributions to the family economy reduce while she is breastfeeding. The significant opportunity costs of breastfeeding are further exemplified by findings that breastfeeding mothers often engage in fewer subsistence and domestic tasks than non-breastfeeding women\u003csup\u003e24,44–46\u003c/sup\u003e. Allomaternal care can offset these costs, but its effect depends on the type of support. When kin provide food or labour support, mothers can sustain longer breastfeeding. By contrast, when kin provide direct childcare, opportunity costs may increase, since maternal subsistence work must be combined with frequent separations from the infant \u003csup\u003e12,47–49\u003c/sup\u003e. These proximate dynamics help explain why maternal relatedness had smaller average effects in our models than those of children or fathers.\u003c/p\u003e\n\u003cp\u003eSelf-reported reasons for weaning provide additional proximate evidence. Opportunity costs were the most frequently cited reason for stopping breastfeeding, particularly in patrilocal households where women face greater labour demands. Social norms were also cited, especially in matrilocal households, suggesting that maternal behaviour is shaped both by ecological and kinship contexts and by culturally transmitted expectations. While the qualitative sample was small, these reports align closely with the evolutionary patterns identified, and this opens the possibility for future research on the proximate motivations for weaning.\u003c/p\u003e\n\u003cp\u003eTaken together, our results show how inclusive fitness theory can illuminate the dynamics of breastfeeding. Breastfeeding is not solely a maternal choice: it is shaped by kinship structure, bargaining power, and conflicting fitness interests between mothers, fathers, children and other co-resident household members. By linking residence patterns, relatedness, and breastfeeding duration, our study demonstrates that kin selection and sexual conflict together provide a powerful framework for explaining why mothers often cease breastfeeding earlier than health guidelines recommend. Here we show how the family structure, and the relatedness of children and parents to their co-resident household members are shaping breastfeeding duration and it is misleading to interpret reproductive decision-making in the context of mothers alone.\u0026nbsp;\u003c/p\u003e"},{"header":"Methods ","content":"\u003cp\u003e\u003cstrong\u003eDescriptive statistics\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study draws on data on 353 female respondents (mothers to 580 children for whom complete information were available for analysis) collected from five regions in western China, each differing in ecology, economy, and culture but sharing a common religion and political administration (Figure 5; SI Tables 2.1 and 3.1). The study sites include two areas in the Gannan Tibetan Autonomous Prefecture of Gansu Province (Zhuoni and Maqu), two in the Garz\u0026ecirc; Tibetan Autonomous Prefecture of Sichuan Province (Zhaba and Lugu), and one in the Diqing Tibetan Autonomous Prefecture of Yunnan Province (Shangrila). Within each region, data were collected from multiple villages clustered by language, cultural identity, and ecological context (Figure 5). This area is distinctive for the coexistence of four post-marital residence patterns\u0026mdash;patrilocal, matrilocal, duolocal, and neolocal\u0026mdash;among neighbouring Tibetan communities of farmers and herders. These contrasting kinship systems generate marked variation in the average relatedness of children and parents to their co-resident household members (Figure 3; SI Table 1).\u003c/p\u003e\n\u003cp\u003eThe main sources of household income vary across regions. In Maqu, yak and sheep herding provide the principal livelihood, with crops largely reserved for household or livestock consumption\u003csup\u003e50,51\u003c/sup\u003e. The seasonal collection of \u003cem\u003eyartsa gunbu\u003c/em\u003e (caterpillar fungus) supplements income but has declined in recent decades \u003csup\u003e52\u003c/sup\u003e. Zhuoni families engage in both barley cultivation and livestock rearing, earning cash income through herding, farming, or temporary wage labour in nearby towns \u003csup\u003e53\u003c/sup\u003e. In Zhaba, Lugu, and Shangrila, most families rely on farming, supplemented by limited herding, foraging for mushrooms and medicinal fungi, or occasional tourism work. Income from wage labour and tourism is irregular and fluctuates annually, and salaried or office-based employment remains rare in all five regions \u003csup\u003e24,54\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eDespite shared Buddhist traditions and other cultural similarities, these Tibetan populations differ in kinship organisation and post-marital residence. Maqu and Zhuoni, inhabited by Amdo Tibetans, follow patrilineal descent and predominantly patrilocal residence \u003csup\u003e55\u003c/sup\u003e. Zhaba and Lugu, in contrast, are matrilineal societies practising duolocal residence \u003csup\u003e24,56\u003c/sup\u003e. Shangrila, located in the Diqing Tibetan Prefecture and inhabited by Kang Tibetans, is characterised by matrilineal descent and matrilocal residence \u003csup\u003e22\u003c/sup\u003e. These regional contrasts provide a unique opportunity to examine how variation in kinship and household composition shapes breastfeeding practices within a single ethnolinguistic population.\u003c/p\u003e\n\u003cp\u003eWe conducted household surveys in five regions of western China, walking from one household to another accompanied by local assistants in each area. The survey consisted of two sections: household structure and individual details. For household data, we collected socio-demographic information from the household head or another knowledgeable adult when the head was absent. These data included all co-resident members\u0026rsquo; years of birth and marriage, parental identities, dispersal histories, frequency of residence in the household, financial status, and primary subsistence activities.\u003c/p\u003e\n\u003cp\u003eIndividual questionnaires were administered separately to adult men and women and recorded marital histories, sibling composition, and reproductive histories. Female respondents provided detailed information on each child\u0026rsquo;s birth date, delivery method, breastfeeding duration, supplementary feeding practices, and reasons for weaning. Although demographic data were collected for all adult household members, this study focuses on families with children born after 2010 to ensure accurate recall of breastfeeding histories and residence arrangements. This yielded complete breastfeeding data for 580 children (284 daughters and 296 sons; SI Table 2). Breastfeeding cessation was defined as the termination of all suckling and censored at 24 months, because of low reliability of longer reported duration and consistently with the physiological relevance of the behaviour, as per with WHO health recommendations \u003csup\u003e57\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eHouseholds were categorised into four post-marital residence patterns: patrilocal (wives disperse to husbands\u0026rsquo; households), matrilocal (husbands disperse to wives\u0026rsquo; households), duolocal (neither spouse disperses), and neolocal (both disperse to form new households). Although residence typically corresponds to prevailing descent systems in each region, exceptions occur\u0026mdash;for example, matrilocal families within predominantly patrilineal communities. The distribution of residence patterns varied: duolocal residence was most common in Zhaba (53.4%) and present at lower frequencies in Lugu (16.5%), while patrilocality predominated in Zhuoni (63.1%) and Maqu (48.8%). In Shangrila, matrilocality was the dominant pattern (47%) (SI Table 1). Neolocal families exist in all locations (Lugu 35.9%, Maqu 28.9%, Shangrila 16.9%, Zhaba 16.8%, Zhuoni 16.9%).\u003c/p\u003e\n\u003cp\u003e\u003cimg 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\"\u003e\u003c/p\u003e\n\u003cp\u003eTo complement the quantitative analysis and gain insight into proximate motivations for weaning, we conducted semi-structured interviews with 44 women in Shangrila. Participants were asked to describe their reasons for stopping breastfeeding, which we subsequently classified into four categories: physical costs, social norms, opportunity costs, and other reasons (Table 2; see SI Table 3 for detailed responses).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCausal model\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe comparison of hypotheses in this study is complicated by potential equifinality\u0026mdash;that is, different hypotheses, described as causal models, can produce similar patterns in the data, making them difficult to distinguish empirically. This issue arises because of the mechanism of genetic inheritance, which correlates the relatedness of children and parents to other household members. Consequently, it becomes challenging to disentangle whether observed effects are driven primarily by the parent\u0026rsquo;s relatedness, the child\u0026rsquo;s relatedness, or both (see Supplementary Information, Section 2, for a detailed discussion of the implications for causal inference). To address these complexities and the non-mutually exclusive nature of our hypotheses, we employ a multi-method approach combining causally validated Cox regression models with comparisons between synthetic datasets (see Supplementary Information, Section 5) and empirical data on household demographics and breastfeeding durations collected in 2016\u0026ndash;2017.\u003c/p\u003e\n\u003cp\u003eFirst, we use a principled causal framework to guide both model specification and interpretation. Specifically, we employ Directed Acyclic Graphs (DAGs) to clarify the assumed relationships among variables and define the appropriate adjustment set for inference. Figure 7 illustrates the variables included in our analysis. As our main goal is to estimate the direct effects of the mother\u0026rsquo;s, father\u0026rsquo;s, and child\u0026rsquo;s average relatedness on breastfeeding duration (tested in Model 3), the key predictors include these three variables, along with village to account for cultural and ecological variation. We additionally control for household size, and for maternal birth cohort, child sex, and birth order to improve estimate precision. All variables are described in detail in Supplementary Information, Section 3.1.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe used Cox proportional-hazards regressions to test which variables were associated with the termination of breastfeeding, treating the process as a survival analysis where predictors\u0026mdash;such as relatedness of individual relatedness and other covariates\u0026mdash;affects the risk of breastfeeding cessation. This approach also accommodates censoring, accounting for children who were still breastfed at the time of the interview; Breastfeeding durations exceeding 24 months were censored due to both the lower reliability of maternal recall and the reduced physiological relevance of breastfeeding beyond this period for mother and child (see SI Figure 2 for complete data distribution).\u003c/p\u003e\n\u003cp\u003eControl variables included the mother\u0026rsquo;s birth cohort, child\u0026rsquo;s birth order and sex, and household size (except in Model 2, where household size lies on the causal path of residence type). Mothers\u0026rsquo; birth cohorts were grouped in ten-year intervals (\u0026le;1980, 1980\u0026ndash;1989, \u0026ge;1990). Because some mothers contributed more than one child to the dataset, maternal ID was included as a random effect, along with village, to control for ecological and cultural clustering. Household size was entered as an ordinal, monotonically increasing predictor. Household size varied across residence patterns (duolocal: 7.77 \u0026plusmn; 2.92; neolocal: 5.50 \u0026plusmn; 1.40; patrilocal: 6.83 \u0026plusmn; 1.90; matrilocal: 6.78 \u0026plusmn; 1.92).\u003c/p\u003e\n\u003cp\u003eAverage genetic relatedness for each individual (child, mother and father) to their co-resident household members was calculated using the Kinship2 package (version 1.9.6) based on pedigree data, following standard formulations from Hamilton (1964). Bayesian Cox models were implemented in Stan with weakly regularizing priors (details in SI section 4). Models were run using the CmdStan package (version 0.5.3) for 3,000 iterations after 1,000 warm-up iterations. Model convergence was verified by R̂ \u0026asymp; 1 and large effective sample sizes. Plots were generated using the ggplot2, contsurvplot, rnaturalearth, and ggspatial packages. All analyses were performed in R (version 4.2.2). Data and reproducible code are available at: https://github.com/lalla-ilaria/breastfeeding_relatedness. Ethical clearance was obtained from University College London and Lanzhou University.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSimulations addressing risk of equifinality\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAdditionally, we conducted further analyses to account for the fact that children and their parents share, on average, half of their genomes. This biological reality creates a correlation between the average relatedness of children and that of their parents to other household members, introducing the potential for equifinality\u0026mdash;the risk that different causal hypotheses could generate similar observable patterns.\u003c/p\u003e\n\u003cp\u003eTo address this, we generated multiple simulated datasets of breastfeeding duration under each hypothesis (H1\u0026ndash;H3) and compared the results of Model 3\u0026mdash;which includes predictors for the relatedness of children, mothers, and fathers\u0026mdash;when fitted to both real and simulated data (Figure 4). We also repeated this comparison using alternative Cox models that included different combinations of relatedness predictors (e.g., only one at a time or pairwise combinations) to evaluate their ability to discriminate among hypotheses (see Supplementary Figure 6).\u003c/p\u003e\n\u003cp\u003eModel 3, which incorporates all three relatedness variables alongside the control covariates, provided an accurate performance in distinguishing among the hypothesised mechanisms and mitigating equifinality (see Supplementary Information, Section 3.3). This approach using simulations is particularly advantageous because, unlike fully parametric models, Cox regressions do not specify a complete likelihood for event times, precluding standard posterior predictive checks for model validation. Instead, we employ a simulation-based validation strategy: by generating datasets under competing hypotheses and refitting the same model to these synthetic data, we assess which of the underlying mechanisms considered here is most consistent with the observed posterior distributions.\u003c/p\u003e"},{"header":"References ","content":"\u003col\u003e\n \u003cli\u003eHrdy, S. B. \u003cem\u003eMothers and Others: The Evolutionary Origins of Mutual Understanding\u003c/em\u003e. (Harvard Univ. Press, 2009).\u003c/li\u003e\n \u003cli\u003eMace, R. \u0026amp; Sear, R. Are humans cooperative breeders? in \u003cem\u003eGrandmotherhood: The Evolutionary Significance of the Second Half of Female Life\u003c/em\u003e (eds Voland, E., Chasiotis, A. \u0026amp; Schiefenh\u0026ouml;vel, W.) 143\u0026ndash;159 (Rutgers Univ. Press, 2005).\u003c/li\u003e\n \u003cli\u003eBove, R. B., Valeggia, C. R. \u0026amp; Ellison, P. T. 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Biol.\u003c/em\u003e 7, 17\u0026ndash;52 (1964).\u003c/li\u003e\n \u003cli\u003eWright, S. Coefficients of inbreeding and relationship. \u003cem\u003eAm. Nat.\u003c/em\u003e 56, 330\u0026ndash;338 (1922).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-4113827/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4113827/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Breastfeeding provides substantial benefits to infants, yet mothers frequently cease breastfeeding earlier than health guidelines recommend. In cooperative breeding systems, maternal decisions such as the duration of breastfeeding are influenced not only by her own costs and benefits, but also by those of other household members, which are weighed by their relatedness to the child and the parents. We take advantage of variation in post-marital residence patterns among Tibetan communities in southwest China to examine how kinship structure shapes breastfeeding. Analysing feeding histories of 580 children across four residence types (patrilocal, matrilocal, duolocal, and neolocal), we show that average relatedness to co-resident family members is systematically associated with breastfeeding duration. Children and mothers who are more closely related to household members experience longer breastfeeding, while higher paternal relatedness is linked to earlier cessation. These patterns are consistent with conflicts of interest predicted by inclusive fitness theory: parent–offspring conflict and sexual conflict between mothers and fathers. Our findings highlight how family structure within households influences parental investment and cooperation in the family.","manuscriptTitle":"Kin selection and sexual conflict shape variation in breastfeeding duration","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-12-12 13:13:32","doi":"10.21203/rs.3.rs-4113827/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"416fc244-4af7-46a8-8094-7b8461c73e73","owner":[],"postedDate":"December 12th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":59542758,"name":"Biological sciences/Evolution/Anthropology/Biological anthropology"},{"id":59542759,"name":"Biological sciences/Evolution/Evolutionary theory"}],"tags":[],"updatedAt":"2025-12-17T17:29:13+00:00","versionOfRecord":[],"versionCreatedAt":"2025-12-12 13:13:32","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4113827","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4113827","identity":"rs-4113827","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}