Women with infertility complying with and resisting polygyny : an explorative qualitative study in urban Gambia

Background. In many low-and middle-income countries women with infertility are often in polygynous marriages. From a human and women's rights perspective, the practice of polygyny is commonly understood as harmful. Studies indicate that polygyny aggravates negative life circumstances of women with infertility with respect to their health and social well-being. The purpose of this qualitative study is to explore how women with infertility experience polygyny and to understand their decision-making regarding these marriages.Methods. An explorative qualitative study was conducted among women with infertility in the urban communities of the West Coast region of The Gambia using in-depth interviews (30). Data analysis involved an emergent and partially inductive thematic framework and was carried out using NVivo 11.Results. With the exception of some women with infertility who described positive experiences within polygynous marriages, most women emphasised conflicts that exist within polygynous households and reported financial and emotional difficulties. Thematic analysis identified several strategies of women with infertility to cope with and resist polygynous marriages, including overcoming childlessness, addressing conflict, spending time outside the compound, looking for social support, kanyaleng kafoolu, living separately and initiating divorce. Moreover, the experiences and decision-making power of women with infertility when it comes to polygynous marriages was found to be closely related to their socio-demographic background.Conclusion.This work highlights how women with infertility in polygynous marriages are in a precarious situation in urban Gambia. Women utilize a mix of compliance, coping and resistance strategies to navigate the challenges of polygynous marriages in a structurally constraining context

Strong gender differences in reproductive success variance, and the times to the most recent common ancestors

The Time To the Most Recent Common Ancestor (TMRCA) based on human mitochondrial DNA (mtDNA) is estimated to be twice that based on the non-recombining part of the Y chromosome (NRY). These TMRCAs have special demographic implications because mtDNA is transmitted only from mother to child, and NRY from father to son. Therefore, mtDNA reflects female history, and NRY, male history. To investigate what caused the two-to-one female-male TMRCA ratio in humans, we develop a forward-looking agent-based model (ABM) with overlapping generations and individual life cycles. We implement two main mating systems: polygynandry and polygyny with different degrees in between. In each mating system, the male population can be either homogeneous or heterogeneous. In the latter case, some males are `alphas' and others are `betas', which reflects the extent to which they are favored by female mates. A heterogeneous male population implies a competition among males with the purpose of signaling as alphas. The introduction of a heterogeneous male population is found to reduce by a factor 2 the probability of finding equal female and male TMRCAs and shifts the distribution of the TMRCA ratio to higher values. We find that high male-male competition is necessary to reproduce a TMRCA ratio of 2: less than half the males can be alphas and betas can have at most half the fitness of alphas. In addition, in the modes that maximize the probability of having a TMRCA ratio between 1.5 and 2.5, the present generation has 1.4 times as many female as male ancestors. We also tested the effect of sex-biased migration and sex-specific death rates and found that these are unlikely to explain alone the sex-biased TMRCA ratio observed in humans. Our results support the view that we are descended from males who were successful in a highly competitive context, while females were facing a much smaller female-female competition

Polygamy in the Marsh Harrier, Circus aeruginosus: Individual Variation in Hunting Performance and Number of Mates

1. Theories postulating that sexual task differentiation may lead to polygamy such that the sex investing the least effort in raising the offspring, engages in simultaneous matings, contrast with polygyny in raptors where the male provides most of the food for its females and nestlings. A field study was undertaken to describe parental effort and success in marsh harriers of different mating status to elucidate this controversy. 2. Data on clutch size and laying date were collected on 421 nests in two Dutch land reclamations, Flevoland and Lauwersmeer. 156 nests were known to have monogamous parents, 30 males had two females and nests. Bigamous males raised on average twice as many fledglings (5.7) than monogamous males (3.0). However, their primary females had more success (3.5) than secondary females (2.3), related to increased nestling mortality in secondary nests. Male fledglings were significantly heavier in primary than in secondary nests. 3. Nest observations made on 22 nests (5 of monogamous, 17 of polygamous males) revealed that daily prey deliveries by males were fewer in mono- than in bigamous males. The latter delivered prey by preference to their primary nests. The prey delivered by a trigamous male were consistently larger than those of a bigamous and monogamous male in the same area. 4. Time budget observations revealed that hunting effort was maximal in the nestling phase (ca 8 hrs foraging per day for all three males observed; at other times of year foraging was reduced in early morning and late afternoon. Net hunting yield (prey brought to nests per hour of hunting) increased in three males with their number (1, 2, or 3) of mates. With progress of the breeding season, male hunting ranges extended further outside the breeding territories and had a great measure of overlap, suggesting that territory quality was not a major factor in male hunting yield. 5. Secondary females participated in provisioning for the nestlings more than primary or monogamy-females, thus compensating for reduced male prey deliveries. 6. Classical polygyny theory addresses the question of female choice: which benefits compensate a secondary female for reduced breeding success by mating with an already paired male? Several hypotheses (enhanced offspring survival, offspring genetic quality, parent chances of future reproduction) are discussed, but evidence is nearly completely lacking. 7. An alternative approach stresses the male's role in the decision process. Males may have more interindividual variation in their capacity to bring food than females in their capacity to lay and incubate eggs. Optimal strategies for males would then range with increasing quality from non-breeding via polyandry and monogamy to polygyny. In species like harriers, non-breeding may be optimal for yearling males with submaximal hunting skills, thus creating a skewed sex ratio forcing some females to accept secondary status as mate of older, high quality males. Polygyny is then associated with slower male than female maturation. The evolution of polyandrous traits in species living isolated in poor environments is likewise explained by this model.

The Evolution of Male-Biased Dispersal under the Joint Selective Forces of Inbreeding Load and Demographic and Environmental Stochasticity

Acknowledgments We thank G. Bocedi, S. Palmer, and three anonymous reviewers for helpful comments on earlier drafts. R.C.H. was funded by the Natural Environment Research Council (1271380). Simulations were performed on the University of Aberdeen’s Maxwell high performance computing cluster.Peer reviewedPublisher PD

Polygyny in Islamic Law and Pukhtun Practice

This is a postprint (accepted manuscript) version of the article published in Ethnology 47(3):181-93. The final version of the article can be found at http://www.jstor.org/stable/25651559 (login required to access content). The version made available in Digital Common was supplied by the author.Accepted Manuscripttru

Variation in grouping patterns, mating systems and social structure: what socio-ecological models attempt to explain

Socio-ecological models aim to predict the variation in social systems based on a limited number of ecological parameters. Since the 1960s, the original model has taken two paths: one relating to grouping patterns and mating systems and one relating to grouping patterns and female social structure. Here, we review the basic ideas specifically with regard to non-human primates, present new results and point to open questions. While most primates live in permanent groups and exhibit female defence polygyny, recent studies indicate more flexibility with cooperative male resource defence occurring repeatedly in all radiations. In contrast to other animals, the potential link between ecology and these mating systems remains, however, largely unexplored. The model of the ecology of female social structure has often been deemed successful, but has recently been criticized. We show that the predicted association of agonistic rates and despotism (directional consistency of relationships) was not supported in a comparative test. The overall variation in despotism is probably due to phylogenetic grade shifts. At the same time, it varies within clades more or less in the direction predicted by the model. This suggests that the model's utility may lie in predicting social variation within but not across clades