Social sciences

  • Supplement |

    The government is stepping up efforts to attract international scientists, as the country invests record sums in research.

    • Smriti Mallapaty
  • Supplement |

    Although not a major scientific player, India hopes that attracting foreign researchers will help it achieve its ambitions.

    • T.V. Padma
  • Letter |

    In human societies, individuals who violate social norms may be punished by third-party observers who have not been harmed by the violator; this study suggests that a reason why the observers are willing to punish is to be seen as more trustworthy by the community.

    • Jillian J. Jordan
    • , Moshe Hoffman
    •  & David G. Rand
  • Letter |

    Centennial-scale variations in methane carbon isotope ratios are attributed to changes in pyrogenic and biogenic sources that can be correlated with anthropogenic activities, such as varying levels of biomass burning during the period of the Roman empire and the Han dynasty, and changes in natural climate variability.

    • C. J. Sapart
    • , G. Monteil
    •  & T. Röckmann
  • Letter |

    Political mobilization messages delivered to 61 million Facebook users during the 2010 US congressional elections directly influenced political self-expression, information seeking and real-world voting behaviour of millions of people and their friends, with social transmission occurring mainly between close friends and having a greater effect than the direct effect of the messages themselves.

    • Robert M. Bond
    • , Christopher J. Fariss
    •  & James H. Fowler
  • Letter |

    Biodiversity threats from Red Lists are linked with patterns of international trade, identifying the ultimate instigators of the threats; developed countries tend to be net importers of implicated commodities, driving biodiversity decline in developing countries.

    • M. Lenzen
    • , D. Moran
    •  & A. Geschke
  • Letter |

    Cooperation in evolutionary games can be stabilized through punishment of non-cooperators, at a cost to those who do the punishing. Punishment can take different forms, in particular peer-punishment, in which individuals punish free-riders after the event, and pool-punishment, in which a fund for sanctioning is set up beforehand. These authors show that pool-punishment is superior to peer-punishment in dealing with second-order free-riders, who cooperate in the main game but refuse to contribute to punishment.

    • Karl Sigmund
    • , Hannelore De Silva
    •  & Christoph Hauert
  • Letter |

    Removing the protected status from poorly performing conservation areas, selling the land and using the money better elsewhere is controversial, but has a simplistic appeal. Here, it is shown that such degazetting can reap significant conservation benefits, even for the well-designed Australian network of protected areas, and even when there is a significant economic cost to transferring protected status to a new area.

    • Richard A. Fuller
    • , Eve McDonald-Madden
    •  & Hugh P. Possingham
  • Letter |

    Network theory has become pervasive in all sectors of biology, from biochemical signalling to human societies, but identification of relevant functional communities has been impaired by many nodes belonging to several overlapping groups at once, and by hierarchical structures. These authors offer a radically different viewpoint, focusing on links rather than nodes, which allows them to demonstrate that overlapping communities and network hierarchies are two faces of the same issue.

    • Yong-Yeol Ahn
    • , James P. Bagrow
    •  & Sune Lehmann
  • Letter |

    Mentors influence the future success of their protégés, but to what extent do those protégés emulate their mentors? Here, one aspect of mentor emulation is studied, namely fecundity — the number of protégés a mentor trains. Analysis of data from the Mathematics Genealogy Project shows that although mentorship fecundity correlates with success, those mentors who maintain a small fecundity go on to train protégés with a larger fecundity. Moreover, the mentor's career stage influences the eventual fecundity of their protégés.

    • R. Dean Malmgren
    • , Julio M. Ottino
    •  & Luís A. Nunes Amaral
  • Letter |

    Social science hypotheses suggest that humans prefer more equality in outcome distributions because the knowledge of inequality reduces the reward experience. Here, functional MRI was used to test directly for inequality-averse social preferences in the brain during monetary transfers between pairs of participants and an experimenter. The results indicate that the brain's reward circuitry is sensitive to distribution inequality and is actively modulated relative to context.

    • Elizabeth Tricomi
    • , Antonio Rangel
    •  & John P. O’Doherty
  • Letter |

    Peptide hormones such as oxytocin and vasopressin influence social behaviour in several mammalian species. Here it is shown that a population of interneurons in the rat olfactory bulb releases vasopressin, and that vasopressin signalling is required in the olfactory system for proper social recognition in rats. Although vasopressin may not work in exactly the same way in humans, social recognition mediated by experience-dependent vasopressin release may be common.

    • Vicky A. Tobin
    • , Hirofumi Hashimoto
    •  & Mike Ludwig