1] Program for Evolutionary Dynamics, Harvard University, Cambridge, Massachusetts 02138, USA [2] Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA [3].
1] Department of Psychology, Yale University, New Haven, Connecticut 06511, USA [2] Department of Economics, Yale University, New Haven, Connecticut 06511, USA [3].
Nature. 2014 Jul 10;511(7508):220-3. doi: 10.1038/nature13530. Epub 2014 Jun 25.
Overexploitation of renewable resources today has a high cost on the welfare of future generations. Unlike in other public goods games, however, future generations cannot reciprocate actions made today. What mechanisms can maintain cooperation with the future? To answer this question, we devise a new experimental paradigm, the 'Intergenerational Goods Game'. A line-up of successive groups (generations) can each either extract a resource to exhaustion or leave something for the next group. Exhausting the resource maximizes the payoff for the present generation, but leaves all future generations empty-handed. Here we show that the resource is almost always destroyed if extraction decisions are made individually. This failure to cooperate with the future is driven primarily by a minority of individuals who extract far more than what is sustainable. In contrast, when extractions are democratically decided by vote, the resource is consistently sustained. Voting is effective for two reasons. First, it allows a majority of cooperators to restrain defectors. Second, it reassures conditional cooperators that their efforts are not futile. Voting, however, only promotes sustainability if it is binding for all involved. Our results have implications for policy interventions designed to sustain intergenerational public goods.
如今，可再生资源的过度开发给后代的福利带来了高昂的代价。然而，与其他公共物品博弈不同的是，后代无法对今天的行为做出回应。有哪些机制可以维持与未来的合作？为了回答这个问题，我们设计了一种新的实验范例，即“代际物品博弈”。一系列连续的群体（代际）可以选择将资源耗尽或为下一个群体留下一些资源。耗尽资源可以使当代人的收益最大化，但会使所有后代都空手而归。我们发现，如果个体做出开采决策，资源几乎总是会被耗尽。这种与未来的合作失败主要是由少数过度开采资源的人造成的，他们开采的资源远远超过可持续的水平。相比之下，如果通过投票来民主地决定开采，资源就会持续得到维持。投票之所以有效有两个原因。首先，它允许大多数合作者来约束背叛者。其次，它向有条件的合作者保证，他们的努力并非徒劳。然而，只有当所有相关方都受到约束时，投票才能促进可持续性。我们的研究结果对旨在维持代际公共物品的政策干预具有重要意义。
