Prosociality has been proposed as a hallmark of humanity1, and studies on prosociality in our closest living relatives have long corroborated the idea that such behavior is uniquely human (e.g.2,3 but see4). A major drawback is that experimental methods for studying prosociality differ dramatically, particularly between human and non-human studies, and that many experiments lack ecological relevance5. For example, in humans most of these tests are computerized cooperation tasks or public goods games performed in peer groups of college students who anonymously make decisions about an interaction partner they do not know and will never need to interact with in the future. However, that is not the social environment on which selection acted during the evolution of humans’ so-called “hyper-cooperation”6, and recent studies showed that when for example some sort of competition7 or hierarchy8 is added to the original cooperation or public goods games, human prosociality/cooperation breaks down easily. Moreover, these economic games are relatively artificial and their ecological relevance is rather unclear9. Therefore, here we tested human prosociality in our own everyday situation, which may reflect the competitive environment in which prosociality possibly evolved. As most of us are not hunting animals on the savanna anymore, we choose a contemporary competitive environment, namely academia.

Science is becoming one of the most competitive professional fields10. Whilst the percentage of young people that finish a Ph.D. has doubled over the last two decades, the amount of available jobs in science has not. Tenured positions are becoming increasingly scarce, and additionally, around the globe governmental funding for research projects has either plateaued or declined11. As a consequence, it has been suggested that researchers are not always willing to share their data, since they are scared of being ‘scooped’ by their competitors12; i.e. another scientist publishes first, and therefore, gets the credit for a theory/hypothesis or results instead of the one sharing it initially. Here, we investigated researchers’ willingness to share their research in detail. In particular, we tested the effect of the scientists’ career status, the costs and benefits of sharing, and the effect of the different sex-combinations of requester and responder.

We were interested in the effect of different sex combinations because men and women are known to differ in the specific social contexts that trigger prosocial acts. There are some reports that women are kinder than men (e.g.13), yet in general, men and women do not differ in their overall amount of cooperation or prosociality (meta-analyses on social dilemmas14; and on economic games15). However, differences start to emerge when a social or emotional context is provided or when they can take their time and freely think over a social decision15. Academia is far from a neutral environment and competition in science is much harsher for women than for men. For example, women are expected to be less brilliant across academic disciplines16, are less likely to be hired for faculty positions17,18,19 or to receive funding18, and hence, are significantly underrepresented at the professor level20.

Moreover, sex-combinations may influence cooperation in different ways. For example, male-male combinations are reported to be more cooperative than female-female combinations14,21. Such male-male alliances may have a cultural background in so called “Old Boy” networks22, and a more evolutionary history in which particularly male bonds were promoted to cope with inter-group conflicts; i.e. the Male Warrior Hypothesis23. Alternatively, males may be more prosocial towards females to impress them24, which may even lead to competitive altruism among those men25 and may increase mating success26. Similarly, high-ranking individuals (cf. leaders) may signal their status by providing benefits to their group members27. Alternatively, low status may enhance prosocial behavior28, and for example, in highly despotic primate species low-ranking individuals may use prosociality towards higher-ranking individuals to gain future tolerance and or support29. Furthermore, the status of scientists does influence how much competition they experience, since older/higher-ranking scientists may already have tenure, and their chances to receive grants are much higher11. Moreover, sex and status may interact since around the world males are culturally associated with power30. Finally, costs of acting prosocial may influence decisions to do so (e.g.31).

Specifically, in this study in a low-cost condition we sent an email to researchers who had recently published in the fields of comparative psychology and social cognition, requesting a PDF of one of their recent publications. We chose these two fields to ensure plausibility of the requests with regard to the field in which we (the authors) work. Emails were sent by two master students (LB: ♀ & BS: ♂) and two post doctoral researchers (MEK: ♀ & JJMM: ♂, similar in age, year of PhD, H-index and international network), all using a university email-address, and the different participants were assigned semi-randomly to those four researchers (each an equal share); i.e. randomly, yet trying to keep the sex ratio of participants equal among all four researchers and while making sure that the two post-docs did not know the participants they emailed personally (to avoid favors among friends: cf.32). Second, in the high-cost condition, we semi-randomly choose a subset of those former low-cost participants; i.e. randomly and independent from their previous response, yet making sure that they had published a data-paper of which the data would be suitable for a potential meta-analyses. These participants were then emailed by one of the other researchers (again semi-randomly assigned: as above) and were asked whether they in principle were willing to share data of one of their studies for a meta-analyses on a related topic. Note that we deliberately did not ask for the data yet, and that we also did not receive any data. Also note that we did not offer any co-authorships or anything else. Informed consent was acquired afterwards; i.e., all participants received an email explaining the purpose of the study and were allowed to retract their responses from the sample. For the full text of all three emails please see the supplementary information (SI). In total 288 out of 292 participants (142 females with average h-index of 9.2 (SD = 9.3) and 146 males with an average h-index of 16.2 (SD = 15.5); from 32 countries all over the world) allowed us to use their responses with regard to our request for a paper for analyses, and 106 out of 110 participants (49 females with average h-index of 22.6 (SD = 15.2) and 57 males with average h-index of 13.7 (SD = 13.4) allowed us to use their responses with regard to the data request for further analyses.