Aaron D. Lightner , Anne C. Pisor , Edward H. Hagen
{"title":"In need-based sharing, sharing is more important than need","authors":"Aaron D. Lightner , Anne C. Pisor , Edward H. Hagen","doi":"10.1016/j.evolhumbehav.2023.02.010","DOIUrl":null,"url":null,"abstract":"<div><p>Cooperative resource sharing is widespread across cultures, and it was likely critical during much of human evolutionary history for pooling risk. Need-based sharing specifically pools risk by following two cooperative rules: help others when asked, and only request help when in need. In a two-part study, we first expanded an agent-based model of need-based sharing partnerships, adding two types of defection and varying partnership sizes. We show that refusing to help always has a long-term cost, which increases with larger partnerships. In contrast, “greedy” requests that are not based on survival risk carry little-to-no cost. We then conducted an experimental vignette study of osotua, a need-based sharing tradition, with Tanzanian Maasai pastoralists. We found that participants generally complied with osotua requests, but shared larger amounts for requests that were based on survival risk. We conclude by proposing an expanded framework for evolutionary models involving need and fitness interdependence, where the cost asymmetry among types of defection generally favors a decision heuristic where individuals prefer sharing with those in need, but err on the side of generosity when need is uncertain.</p></div>","PeriodicalId":55159,"journal":{"name":"Evolution and Human Behavior","volume":null,"pages":null},"PeriodicalIF":3.0000,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"3","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Evolution and Human Behavior","FirstCategoryId":"102","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1090513823000235","RegionNum":1,"RegionCategory":"心理学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"BEHAVIORAL SCIENCES","Score":null,"Total":0}
引用次数: 3
Abstract
Cooperative resource sharing is widespread across cultures, and it was likely critical during much of human evolutionary history for pooling risk. Need-based sharing specifically pools risk by following two cooperative rules: help others when asked, and only request help when in need. In a two-part study, we first expanded an agent-based model of need-based sharing partnerships, adding two types of defection and varying partnership sizes. We show that refusing to help always has a long-term cost, which increases with larger partnerships. In contrast, “greedy” requests that are not based on survival risk carry little-to-no cost. We then conducted an experimental vignette study of osotua, a need-based sharing tradition, with Tanzanian Maasai pastoralists. We found that participants generally complied with osotua requests, but shared larger amounts for requests that were based on survival risk. We conclude by proposing an expanded framework for evolutionary models involving need and fitness interdependence, where the cost asymmetry among types of defection generally favors a decision heuristic where individuals prefer sharing with those in need, but err on the side of generosity when need is uncertain.
期刊介绍:
Evolution and Human Behavior is an interdisciplinary journal, presenting research reports and theory in which evolutionary perspectives are brought to bear on the study of human behavior. It is primarily a scientific journal, but submissions from scholars in the humanities are also encouraged. Papers reporting on theoretical and empirical work on other species will be welcome if their relevance to the human animal is apparent.