Kin Selection Research Articles

No evidence that relatedness or familiarity modulates male harm in Drosophila melanogaster flies from a wild population.

Sexual selection frequently promotes the evolution of aggressive behaviors that help males compete against their rivals, but which may harm females and hamper their fitness. Kin selection theory predicts that optimal male–male competition levels can be reduced when competitors are more genetically related to each other than to the population average, contributing to resolve this sexual conflict. Work in Drosophila melanogaster has spearheaded empirical tests of this idea, but studies so far have been conducted in laboratory‐adapted populations in homogeneous rearing environments that may hamper kin recognition, and used highly skewed sex ratios that may fail to reflect average natural conditions. Here, we performed a fully factorial design with the aim of exploring how rearing environment (i.e., familiarity) and relatedness affect male–male aggression, male harassment, and overall male harm levels in flies from a wild population of Drosophila melanogaster, under more natural conditions. Namely, we (a) manipulated relatedness and familiarity so that larvae reared apart were raised in different environments, as is common in the wild, and (b) studied the effects of relatedness and familiarity under average levels of male–male competition in the field. We show that, contrary to previous findings, groups of unrelated‐unfamiliar males were as likely to fight with each other and harass females than related‐familiar males and that overall levels of male harm to females were similar across treatments. Our results suggest that the role of kin selection in modulating sexual conflict is yet unclear in Drosophila melanogaster, and call for further studies that focus on natural populations and realistic socio‐sexual and ecological environments.

Social rank and species-specific differences influence cooperation and conflict in anemonefish societies

Many animal groups consist of dominance hierarchies. Theoretical models suggest that higher-ranked individuals should increase aggression but should decrease helping unless the cost of helping decreases with higher rank. Most empirical tests focus on systems with kin selection, whereas tests for groups in which individuals are unrelated are rare. Here we used two anemonefish species to test hypotheses of variation in helping and aggression with respect to social rank. We assessed behavioural frequencies for each rank in Amphiprion percula and A. perideraion groups and performed a removal experiment to determine whether behaviours were rank- or size-specific. Overall, we found A. perideraion performed more aggression and less helping than A. percula , possibly due to a difference in ecological constraints. In both species, we found consistent differences in behaviour between ranks, with higher ranks performing both aggression and helping more often. Despite low relatedness within groups, we found that lower-ranked individuals helped in both species. When we experimentally promoted individuals and controlled for group size, their behaviour became indistinguishable from that of individuals established in the higher rank. Thus, for the first time, we quantified helping for nonbreeding individuals in a marine fish, showed that behavioural patterns are rank-specific, and confirmed that individuals adjust both aggression and helping to their likelihood of inheriting a breeding position. • We studied rank-specific differences in anemonefish aggression and helping. • Helping by nonbreeders may help explain social evolution. • Cooperation and conflict differ between closely related species.

Population viscosity promotes altruism under density-dependent dispersal.

A basic mechanism of kin selection is population viscosity, whereby individuals do not move far from their place of birth and hence tend to be surrounded by relatives. In such circumstances, even indiscriminate altruism among neighbours will often involve interactions between kin, which has a promoting effect on the evolution of altruism. This has the potential to explain altruistic behaviour across the whole tree of life, including in taxa for which recognition of kin is implausible. However, population viscosity may also intensify resource competition among kin, which has an inhibitory effect on altruism. Indeed, in the simplest scenario, in which individuals disperse with a fixed probability, these two effects have been shown to exactly cancel such that there is no net impact of viscosity on altruism. Here, we show that if individuals are able to disperse conditionally upon local density, they are favoured to do so, with more altruistic neighbourhoods exhibiting a higher rate of dispersal and concomitant relaxation of kin competition. Comparing across different populations or species, this leads to a negative correlation between overall levels of dispersal and altruism. We demonstrate both analytically and using individual-based simulations that population viscosity promotes the evolution of altruism under density-dependent dispersal.

The Evolution of Placentation in Flowering Plants: A Possible Role for Kin Selection

Placentation refers to the mode of ovule attachment on the wall of the ovary. In multiovulate ovaries, placentation influences interactions among developing seeds with varying degrees of kinships. Placentation is a taxonomically informative character in flowering plants, yet little has been written about the origin and evolutionary trends of various placentation types in flowering plants since Puri’s and Stebbins’ work, over six decades and almost four decades ago, respectively. More recently, some authors have written about the evolution of placentation in certain groups, but an overall perspective for angiosperms is lacking. For 421 families of angiosperms, we collected data on placentation types and ovule number, and analyzed the data in the phylogenetic context using recent comprehensive phylogeny of angiosperms to test the hypotheses on the evolution of various placentation types and their association with ovule number. The distribution of placentation types across flowering plants suggests that axile placentation, followed by parietal and basal placentation, occurs more frequently than laminar and free central placentation that are very rare. Our results are more consistent with evolutionary trends proposed by Puri than by Stebbins and suggest that marginal placentation is the ancestral and most primitive placentation type, while axile is the most advanced. Placentation types show strong association with ovule number. Finally, our results on ovule number and placentation types indicate that most angiosperms may fall into two categories: one with one or few ovule(s) and basal placentation, and another with many ovules and parietal and axile placentation. Kin selection within ovaries may play a role in explaining the observed patterns. Overall, our results provide new insights into the evolution of placentation, particularly into the drivers underlying the diversification of various placentation types.

Pattern, function and constraint of infant handling in wild Japanese macaques

AbstractIn group‐living primates, non‐mother individuals frequently contact and handle an infant. Although previous studies showed that the function of this behaviour varies among and within species, few have considered a possibility the handlers’ accessibility to an infant may be restricted by a social relationship between the handlers and infants’ mothers. Considering this proximate constraint on the choice and handling of an infant, we aimed to clarify the function of infant handling in wild Japanese macaques (Macaca fuscata). We collected behavioural data on infant handling from 24 mother–infant pairs over three years on Kinkazan Island, Japan. We tested the predictions of three functional hypotheses: learning‐to‐mother, kin selection and reproductive competition among females. We found that handling by males rarely occurred. The proximity between mother and a potential handler positively affected the frequency of infant handling, and its effect interacted with the handler's parity, kinship and relative dominance relationship with the mother. Hence, the effects of handlers’ proximity were prominent for nulliparous, related and relatively lower‐ranked females relative to parous, unrelated and higher‐ranked females. We also found that infants were handled positively in most cases. These results fit the predictions of the learning‐to‐mother hypothesis and kin selection hypothesis, indicating that the functions of infant handling varied with the attributes of the handlers. This study provides rare results clarifying the function of infant handling in wild primates, based on the fact that handler behaviour is constrained by accessibility to the mother.

Differential Selection on Caste-Associated Genes in a Subterranean Termite.

Simple SummarySocial insects can sometimes boldly invade new habitats, including areas of human habitation where they can become unwanted domestic or agricultural pests. In this study, we use molecular sequence analysis to study genetic patterns associated with the invasion and division of labour in the Eastern subterranean termite Reticulitermes flavipes. By studying how genes vary by caste and by population, we show that even termites invasive to a metropolitan city can still harbour plenty of genetic variation, as much or more as native termite populations. We suggest therefore that invasive termites do not necessarily suffer long term loss-of-variation upon invasion. Second, we show that genes associated in their expression with the soldier caste evolve approximately twice as fast as genes expressed by other castes of this species, regardless of from what population the castes were sampled. Why termite soldier genes evolve quickly is not known, but it seems unrelated to invasion or the invaded habitat. Given that soldiers are sterile and thus have no direct fitness, the evidence for gene-level selection in the soldier caste is an intriguing example of kin selection.Analyzing the information-rich content of RNA can help uncover genetic events associated with social insect castes or other social polymorphisms. Here, we exploit a series of cDNA libraries previously derived from whole-body tissue of different castes as well as from three behaviourally distinct populations of the Eastern subterranean termite Reticulitermes flavipes. We found that the number (~0.5 M) of single nucleotide variants (SNVs) was roughly equal between nymph, worker and soldier caste libraries, but dN/dS (ratio of nonsynonymous to synonymous substitutions) analysis suggested that some of these variants confer a caste-specific advantage. Specifically, the dN/dS ratio was high (~4.3) for genes expressed in the defensively specialized soldier caste, relative to genes expressed by other castes (~1.7–1.8) and regardless of the North American population (Toronto, Raleigh, Boston) from which the castes were sampled. The populations, meanwhile, did show a large difference in SNV count but not in the manner expected from known demographic and behavioural differences; the highly invasive unicolonial population from Toronto was not the least diverse and did not show any other unique substitution patterns, suggesting any past bottleneck associated with invasion or with current unicoloniality has become obscured at the RNA level. Our study raises two important hypotheses relevant to termite sociobiology. First, the positive selection (dN/dS > 1) inferred for soldier-biased genes is presumably indirect and of the type mediated through kin selection, and second, the behavioural changes that accompany some social insect urban invasions (i.e., ‘unicoloniality’) may be detached from the loss-of-diversity expected from invasion bottlenecks.

Kin selection for cooperation in natural bacterial populations

Bacteria produce a range of molecules that are secreted from the cell and can provide a benefit to the local population of cells. Laboratory experiments have suggested that these "public goods" molecules represent a form of cooperation, favored because they benefit closely related cells (kin selection). However, there is a relative lack of data demonstrating kin selection for cooperation in natural populations of bacteria. We used molecular population genetics to test for signatures of kin selection at the genomic level in natural populations of the opportunistic pathogen Pseudomonas aeruginosa We found consistent evidence from multiple traits that genes controlling putatively cooperative traits have higher polymorphism and greater divergence and are more likely to harbor deleterious mutations relative to genes controlling putatively private traits, which are expressed at similar rates. These patterns suggest that cooperative traits are controlled by kin selection, and we estimate that the relatedness for social interactions in P. aeruginosa is r = 0.84. More generally, our results demonstrate how molecular population genetics can be used to study the evolution of cooperation in natural populations.

Hamilton's rule: A non-causal explanation?

The explanatory power of Hamilton's rule, the main explanatory principle of social evolution theory, is an ongoing subject of controversy. In this paper, we reinforce the case for the considerable value of the regression-based version of the rule in explaining the evolution of social traits. Although we agree that the rule can have an organizing role in social evolution research, we maintain that it does not explain in virtue of citing causes or providing an organizing framework. Instead, we argue it either provides an explanation by constraint or a non-causal counterfactual explanation.

Distinct kin strategies of the legume soybean and the non-legume balsam by accomplishing different nitrogen acquisition and rhizosphere microbiome composition.

SUMMARYKin selection has been proposed vvto be an important mechanism for plant relatives growing together. To reveal kin recognition, we used15N labeling to assess the short‐term nitrogen (N) acquisition (uptake of nitrate and ammonium), long‐term N utilization (recovery of added urea), N‐use efficiency (NUE) and rhizosphere microbiome in leguminousGlycine maxand non‐leguminousImpatiens balsamina. Individuals of each species were planted pairwise with either a sibling or a stranger. Enzyme activity and soil microbial composition were compared between kinship groups. Compared with strangers,G. maxsiblings increased aboveground biomass, NUE, and nitrogenase activity, whereasI. balsaminasiblings decreased root biomass and increased uptake rate of nitrate and potential nitrification rate. Plant kinship affected soil bacterial communities by enriching specific groups possessing explicit eco‐functions (Rhizobiales forG. maxandNitrospiraforI. balsamina). Kinship‐sensitive operational taxonomic units formed independent modules in the bacterial co‐occurrence network and were positively correlated with plant growth performance, N acquisition and enzymatic activity. Plant kin recognition may depend on the growth strategies of the plant species. Kin selection was dominant inG. maxby enhancing biological N fixation through the enrichment of symbiotic rhizobia (demonstrated by aboveground growth and NUE superiority among siblings). Kin selection and niche partitioning occurred simultaneously inI. balsamina, expressed through reduced root allocation but increased nitrate uptake, and enhanced soil N nitrification, by enriching functional microbial groups. Kin recognition responses are the consequence of complex interactions among the host plant, the microbiome, and soil nutrient cycling and utilization processes.

Ecological Drivers of Non-kin Cooperation in the Hymenoptera

Despite the prominence of kin selection as a framework for understanding the evolution of sociality, many animal groups are comprised of unrelated individuals. These non-kin systems provide valuable models that can illuminate drivers of social evolution beyond indirect fitness benefits. Within the Hymenoptera, whose highly related eusocial groups have long been cornerstones of kin selection theory, groups may form even when indirect fitness benefits for helpers are low or absent. These non-kin groups are widespread and abundant, yet have received relatively little attention. We review the diversity and organization of non-kin sociality across the Hymenoptera, particularly among the communal bees and polygynous ants and wasps. Further, we discuss common drivers of sociality across these groups, with a particular focus on ecological factors. Ecological contexts that favor non-kin sociality include those dominated by resource scarcity or competition, climatic stressors, predation and parasitism, and/or physiological constraints associated with reproduction and resource exploitation. Finally, we situate Hymenopteran non-kin sociality within a broader biological context by extending insights from these systems across diverse taxa, especially the social vertebrates. Non-kin social groups thus provide unique demonstrations of the importance of ecological factors in mediating the evolutionary transition from solitary to group living.

Social immunity in the honey bee: do immune-challenged workers enter enforced or self-imposed exile?

Animals living in large colonies are especially vulnerable to infectious pathogens and may therefore have evolved additional defences. Eusocial insects supplement their physiological immune systems with ‘social immunity’, a set of adaptations that impedes the entrance, establishment, and spread of pathogens in the colony. We here find that honey bee workers (Apis mellifera) that had been experimentally immune-challenged with bacterial lipopolysaccharide (LPS) often exited the hive and subsequently died; some individuals were dragged out by other workers, while others appeared to leave voluntarily. In a second experiment, we found that healthy workers treated with surface chemicals from LPS-treated bees were evicted from the hive more often than controls, indicating that immune-challenged bees produce chemical cues or signals that elicit their eviction. Thirdly, we observed pairs of bees under lab conditions, and found that pairs spent more time apart when one member of the pair had received LPS, relative to controls. Our findings suggest that immune-challenged bees altruistically banish themselves, and that workers evict sick individuals which they identify using olfactory cues, putatively because of (kin) selection to limit the spread of pathogens within colonies.Significance statementJust as in humans, animals living in large groups must contend with infectious diseases. Social insects such as honey bees have evolved a range of behavioural and organisational defences against disease, collectively termed ‘social immunity’. Here, we describe experiments in which we introduced immune-stimulated bee workers into hives to study social immunity. We find that bees that were wounded or immune-challenged were more likely to leave the hive—resulting in their death—compared to healthy controls. Some of the bees leaving the hive were ejected by other workers, while some left the hive seemingly by choice: we thus find evidence for both ‘banishment’ of immune-challenged bees and self-imposed exile. Furthermore, using experiments transferring chemical signals between healthy and immune stimulated bees, we establish that the latter are identified for banishment by the chemicals present on their body surface.

New exploration on bifurcation for fractional-order quaternion-valued neural networks involving leakage delays.

During the past decades, many works on Hopf bifurcation of fractional-order neural networks are mainly concerned with real-valued and complex-valued cases. However, few publications involve the quaternion-valued neural networks which is a generalization of real-valued and complex-valued neural networks. In this present study, we explorate the Hopf bifurcation problem for fractional-order quaternion-valued neural networks involving leakage delays. Taking advantage of the Hamilton rule of quaternion algebra, we decompose the addressed fractional-order quaternion-valued delayed neural networks into the equivalent eight real valued networks. Then the delay-inspired bifurcation condition of the eight real valued networks are derived by making use of the stability criterion and bifurcation theory of fractional-order differential dynamical systems. The impact of leakage delay on the bifurcation behavior of the involved fractional-order quaternion-valued delayed neural networks has been revealed. Software simulations are implemented to support the effectiveness of the derived fruits of this study. The research supplements the work of Huang et al. (Neural Netw 117:67-93, 2019).

Mobbing behaviour in non-breeding flocks of a passerine bird in northern Patagonia

Abstract Animal cooperation occurs in both genetically related and unrelated groups of individuals, involving costs and benefits that have not been fully elucidated. For example, risky behaviour such as mobbing a predator would be selected if participants are genetic relatives because they share a fraction of their gene pool (i.e., kin selection or indirect benefits). However, in the absence of genetic relatedness, benefits can be achieved by direct benefits such as reciprocity or mutualism, among others. In this study we analyzed the cooperative mobbing behaviour in winter flocks of an endemic passerine of the austral temperate forests, the Thorn-tailed rayadito (Aphrastura spinicauda). We first tested whether the probability of and the latency to mobbing response differed depending on the acoustic stimulus perceived by the flock (i.e., conspecific mobbing calls vs. predator calls), and whether the intensity of the mobbing was related to the number of individuals and species participating. We found that flocks were more likely to approach the predator when the acoustic signal was a conspecific mobbing call than when it was the predator’s call, and that the intensity of mobbing increased with the number of participants. Secondly, we explored if the level of kinship within the group potentially played a role in the development of the mobbing behaviour. The proportion of close-relatives found in these flocks was low, and the within- and among-flock degree of kinship did not differ. This suggests that kin selection might not be related with the expression of mobbing behaviour in winter flocks.

The build-up of dominance hierarchies in eusocial insects.

Reproductive division of labour is a hallmark of eusocial insects. However, its stability can often be hampered by the potential for reproduction by otherwise sterile nest-mates. Dominance hierarchy has a crucial role in some species in regulating which individuals reproduce. Compared with those in vertebrates, the dominance hierarchies in eusocial insects tend to involve many more individuals, and should require additional selective forces unique to them. Here, we provide an overview of a series of studies on dominance hierarchies in eusocial insects. Although reported from diverse eusocial taxa, dominance hierarchies have been extensively studied in paper wasps and ponerine ants. Starting from molecular physiological attributes of individuals, we describe how the emergence of dominance hierarchies can be understood as a kind of self-organizing process through individual memory and local behavioural interactions. The resulting global structures can be captured by using network analyses. Lastly, we argue the adaptive significance of dominance hierarchies from the standpoint of sterile subordinates. Kin selection, underpinned by relatedness between nest-mates, is key to the subordinates' acceptance of their positions in the hierarchies. This article is part of the theme issue 'The centennial of the pecking order: current state and future prospects for the study of dominance hierarchies'.

Impact of genetic relatedness and food competition on female dominance hierarchies in a cichlid fish

Kin selection theory predicts that genetic relatedness between group members can reduce the asymmetry in resource partitioning between superior and inferior competitors. In social groups, access to resources is often regulated by dominance hierarchies; thus, the degree of relatedness within a group may have a substantial impact on hierarchy structure. However, evidence of such effects is scarce. This study investigated how genetic relatedness and food competition affect dominance hierarchies in adult female Pelvicachromis taeniatus , a biparental African cichlid that shows kin-directed cooperation during juvenile shoaling and parental care. We compared triads of unfamiliar females, consisting of either a sister pair and an unrelated female (‘mixed’ groups) or three unrelated females (‘nonkin’ groups), and measured food monopolization and hierarchy characteristics (linearity, hierarchy steepness and short-term stability). To determine dominance relationships, we used an automated analysis of approach–avoidance events based on video-tracking data. The females formed hierarchies that remained stable over 2 days and were linear or near linear with one clear alpha female dominating the other two group members. Higher-ranking females tended to have prior access to food and could better sustain their body mass. The steepness of these hierarchies decreased after feeding, showing that dominance behaviour changed plastically depending on the intensity of competition over limited resources. Mixed groups consumed food slower than nonkin groups, but the treatments did not differ in food monopolization or hierarchy characteristics. In conclusion, kin-biased behaviour was highly dependent on life stage and social context: Within the same species, juveniles and mating partners showed increased cooperation, whereas female–female competition and dominance remained unaffected by genetic relatedness. • Dominance hierarchies in nonkin and mixed kinship groups show similar properties. • Hunger intensifies dominance relationships. • The alpha female can better sustain her body mass than lower-ranking competitors. • Dominance behaviours can be automatically analysed using video-tracking software.

Communal breeding by women is associated with lower investment from husbands.

According to Hamilton's rule, matrilineal-biased investment restrains men in matrilineal societies from maximising their inclusive fitness (the 'matrilineal puzzle'). A recent hypothesis argues that when women breed communally and share household resources, a man should help his sisters' household, rather than his wife's household, as investment to the later but not the former would be diluted by other unrelated members (Wu et al., 2013). According to this hypothesis, a man is less likely to help on his wife's farm when there are more women reproducing in the wife's household, because on average he would be less related to his wife's household. We used a farm-work observational dataset, that we collected in the matrilineal Mosuo in southwest China, to test this hypothesis. As predicted, high levels of communal breeding by women in his wife's households do predict less effort spent by men on their wife's farm, and communal breeding in men's natal households do not affect whether men help on their natal farms. Thus, communal breeding by women dilutes the inclusive fitness benefits men receive from investment to their wife and children, and may drive the evolution of matrilineal-biased investment by men. These results can help solve the 'matrilineal puzzle'.

The evolution of altruism and the units of selection problem

In this paper, I will address one of the main issues in the philosophy of biology: the evolution of altruism and cooperation and the related problem of the units of selection. Starting from the so-called paradox of altruism, I will critically examine standard evolutionary models for the resolution of that paradox, and the explanation of altruism. I review and assess the following models of selection: the traditional model of group selection, gene?s eye view, kin selection, direct reciprocity (reciprocal altruism), indirect reciprocity, and the updated version of group selection, namely Sober and Wilson?s model of multilevel selection. In the final section, I will try to explain why is the dismissal of multilevel selection based on its explanatory complexity so common, and why inclusive fitness theory and direct reciprocity are generally sufficient to explain a good part of biological phenomena related to altruism and cooperation.

Questionable All Along, DNA’s Inheritance Role Is Now Failing in a Big Way—Does Anyone Care?

Science’s theory of evolution purports to explain life and its historical dynamics in a physics/material-only fashion. But this entails a broad reliance on DNA (deoxyribonucleic acid) for inheritance (and thus blueprints), which appears to be implausible for a number of unusual innate behaviors. The immediate unfolding challenge, though, is that the inheritance role is conveniently testable via searches for the DNA origins of a number of human behavioral and health tendencies, and despite enormous efforts those searches have thus far largely failed (i.e., the “absolutely beyond belief” missing heritability problem). This existing case for DNA’s inadequacies will be briefly reviewed herein. The subsequent main analysis considers some big challenges facing DNA associated with some evolutionary dynamics—the acquisition of color vision in primates; instinctive behaviors including the egg-laying practices of emerald jewel wasps; kin selection; and our natural religious beliefs. Together these challenges strongly suggest that the acceptance of DNA as the (complete) language of life was premature. The haphazard and ambiguous nature of DNA/genetic specifications is very unlikely to have provided a vehicle for the exacting blueprints required for the many instinctive behaviors or capacities. Life appears to be more complex than biologists believe. Two possible alternative explanations are briefly considered in the wake of these discussions. Finally, does anyone—beginning with academics—care about this unfolding foundational failure?

Identifying Causes of Social Evolution: Contextual Analysis, the Price Approach, and Multilevel Selection

Kin selection theory and multilevel selection theory are distinct approaches to explaining the evolution of social traits. The latter claims that it is useful to regard selection as a process that can occur on multiple levels of organisation such as the level of individuals and the level of groups. This is reflected in a decomposition of fitness into an individual component and a group component. This multilevel view is central to understanding and characterising evolutionary transitions in individuality, e.g., from unicellular life to multicellular organisms, but currently suffers from the lack of a consistent, quantifiable measure. Specifically, the two major statistical tools to determine the coefficients of such a decomposition, the multilevel Price equation and contextual analysis, are inconsistent and may disagree on whether group selection is present. Here we show that the reason for the discrepancies is that underlying the multilevel Price equation and contextual analysis are two non-equivalent causal models for the generation of individual fitness effects (thus leaving different “remainders” explained by group effects). While the multilevel Price equation assumes that the individual effect of a trait determines an individual's relative success within a group, contextual analysis posits that the individual effect is context-independent. Since these different assumptions reflect claims about the causal structure of the system, the correct approach cannot be determined on general theoretical or statistical grounds but must be identified by experimental intervention. We outline interventions that reveal the underlying causal structure and thus facilitate choosing the appropriate approach. We note that kin selection theory with its focus on the individual is immune to such inconsistency because it does not address causal structure with respect to levels of organisation. In contrast, our analysis of the two approaches to measuring group selection demonstrates that multilevel selection theory adds meaningful (falsifiable) causal structure to explain the sources of individual fitness and thereby constitutes a proper refinement of kin selection theory. Taking such refined causal structure into account seems indispensable for studying evolutionary transitions in individuality because these transitions are characterised by changes in the selection pressures that act on the respective levels.

Sex-biased demography modulates male harm across the genome.

Recent years have seen an explosion of theoretical and empirical interest in the role that kin selection plays in shaping patterns of sexual conflict, with a particular focus on male harming traits. However, this work has focused solely on autosomal genes, and as such it remains unclear how demography modulates the evolution of male harm loci occurring in other portions of the genome, such as sex chromosomes and cytoplasmic elements. To investigate this, we extend existing models of sexual conflict for application to these different modes of inheritance. We first analyse the general case, revealing how sex-specific relatedness, reproductive value and the intensity of local competition combine to determine the potential for male harm. We then analyse a series of demographically explicit models, to assess how dispersal, overlapping generations, reproductive skew and the mechanism of population regulation affect sexual conflict across the genome, and drive conflict between nuclear and cytoplasmic genes. We then explore the effects of sex biases in these demographic parameters, showing how they may drive further conflicts between autosomes and sex chromosomes. Finally, we outline how different crossing schemes may be used to identify signatures of these intragenomic conflicts.