Need for Alloparental Care and Attitudes Toward Homosexuals in 58 Countries: Implications for the Kin Selection Hypothesis

AbstractAndrophilia refers to sexual attraction and arousal to adult males, whereas gynephilia refers to sexual attraction and arousal to adult females. The Kin Selection Hypothesis (KSH) posits that genes for male androphilia can persist if androphilic males offset the fitness costs of not reproducing directly by enhancing indirect fitness. In theory, by directing altruistic behavior toward kin, androphilic males can increase the reproduction of kin, thereby enhancing indirect fitness. Evidence supporting the KSH has been documented in Samoa. Samoan transgendered, androphilic males, known locally as fa’afafine, are socially accepted by the majority of Samoans. In contrast, no supportive evidence has been garnered from other cultures (i.e., USA, UK, Japan) that are characterized by less social tolerance toward male androphiles. Tests of the KSH in Canada might be more likely to yield findings consistent with Samoa because Canadian social and political attitudes toward male androphiles are markedly more tolerant and accepting. Here, we compared the willingness of Canadian androphilic men, gynephilic men, and androphilic women to invest in nieces and nephews as well as in non-kin children. Consistent with the KSH and findings from Samoa, androphilic men exhibited a significantly greater cognitive dissociation between altruistic tendencies directed toward kin versus non-kin children relative to gynephilic men and androphilic women. The present study, therefore, provides some tentative support for the KSH from a culture other than Samoa. Findings and future directions for research are considered within the context of the existing cross-cultural literature.

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Sexual selection and the evolution of altruism: males are more altruistic and cooperative towards attractive females

Letters on Evolutionary Behavioral Science ◽

10.5178/lebs.2016.42 ◽

2016 ◽

Vol 7 (1) ◽

pp. 10-13 ◽

Cited By ~ 15

Author(s):

Manpal Singh Bhogal ◽

Niall Galbraith ◽

Ken Manktelow

Keyword(s):

Game Theory ◽

Sexual Selection ◽

Kin Selection ◽

Self Report ◽

Economic Games ◽

Selection Hypothesis ◽

Contemporary Research ◽

Sexual Selection Hypothesis ◽

Game Theoretic

Explaining altruism through an evolutionary lens has been a challenge for evolutionary theorists. Where altruism towards kin is well understood through kin selection, altruism towards non-kin is an evolutionary puzzle. Contemporary research has found that, through a game-theoretic framework, sexual selection could be an explanation for the evolution of altruism. Research suggests that males are more altruistic towards females they are interested in engaging with, sexually or romantically when distributing stakes in economic games. This study, adopting a between-groups design, tested the sexual selection explanation for altruism by asking participants to self-report altruistic and cooperative intention when reading moral scenarios accompanied by attractive or unattractive images. We find that participants, particularly males, report being more altruistic and cooperative when viewing an attractive image of a female. This study replicates the sexual selection hypothesis in explaining altruism through an alternative experimental framework to game theory.

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Haplodiploidy, eusociality and absence of male parental and alloparental care in Hymenoptera: a unifying genetic hypothesis distinct from kin selection theory

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1993.0163 ◽

1993 ◽

Vol 342 (1302) ◽

pp. 335-352 ◽

Cited By ~ 17

Keyword(s):

Genetic Drift ◽

Maternal Care ◽

Kin Selection ◽

Paternal Care ◽

Diploid Species ◽

Alloparental Care ◽

Selection Theory ◽

Long Run ◽

Diploid Populations ◽

Genetic Hypothesis

Beginning with Hamilton ( J. theor. Biol. 7, 1-52 (1964)), evolutionary biologists have attempted to explain the apparent predisposition for the haplodiploid Hymenoptera to evolve both eusociality and female workers. As an alternative to kin selective, pre-adaptational, or ecological explanations for this association, I propose a new genetic hypothesis, the protected invasion hypothesis : dominant alleles for maternal care in finite haplodiploid populations are more resistant to loss from genetic drift than are paternal-care alleles in haplodiploid populations or than are either maternal or paternal-care alleles in diploid populations. Similarly, dominant alleles for female alloparental care in finite haplodiploid populations are more resistant to loss from genetic drift than are male alloparental alleles in haplodiploid populations or than are (male or female) alloparental alleles in diploid populations. A Markov model of phenotypic evolution describing the step-wise progress of a population toward one of two adaptive peaks demonstrates that even small differences in fixation probabilities among these alleles can translate into large differences in the long-run probabilities of observing the corresponding parental or alloparental strategies. Thus the protected invasion hypothesis immediately explains all of the peculiar social features of the haplodiploid Hymenoptera, namely: (i) the overwhelmingly greater tendency for maternal care than paternal care in Hymenoptera; (ii) the greater propensity for eusociality (alloparental sibling care) in Hymenoptera than in diploid insects; and (iii) the greater likelihood for females than males to become alloparents (workers) in the Hymenoptera. The hypothesis also correctly predicts (iv) the apparently higher frequency of paternal care in diploid species than in haplodiploid species, and (v) the lack of a sex-bias among workers of eusocial diploid species. The protected invasion hypothesis is distinct from relatedness-based explanations and provides a more comprehensive explanation for the repeated appearance of the distinctive social structures of the Hymenoptera than does the kin selection model. I show that the bias toward eusociality in Hymenoptera is produced by protected invasion effects even when there is no female-biased sex ratio and no asymmetry between a female’s relatedness to its siblings and to its own offspring. In addition, protected invasion effects create a bias for female versus male workers within the Hymenoptera even when there is no asymmetry between a female’s and male’s relatedness to its siblings. Furthermore, protected invasion effects create a bias toward eusociality in haplodiploid versus diploid populations even when the queen mates an indefinite number of times and there is no difference between haplodiploid and diploid colonies in the relatednesses of workers to their tended brood. Finally, the protected invasion hypothesis explains a phenomenon that cannot be explained by kin selection theory: the surprising overwhelming preponderance of maternal over paternal care in the Hymenoptera (because male and female parents have the same mean relatedness to their offspring when the female mates singly). An important implication of the protected invasion hypothesis is that synergistic co-operation among siblings is more likely to evolve in haplodiploid than in diploid species.

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