Editing Kin selection (section)

===Experimental studies, interviews, and surveys===<!--should be recast to emphasize findings, not research studies-->
Interviews of several hundred women in Los Angeles showed that while non-kin friends were willing to help one another, their assistance was far more likely to be reciprocal.  The largest amounts of non-reciprocal help, however, were reportedly provided by kin.  Additionally, more closely related kin were considered more likely sources of assistance than distant kin.<ref>{{cite journal |last1=Essock-Vitale |first1=S. M. |last2=McGuire |first2=M. T. |year=1985 |title=Women's lives viewed from an evolutionary perspective. II. Patterns in helping |journal=Ethology and Sociobiology |volume=6 |issue=3 |pages=155–173 |doi=10.1016/0162-3095(85)90028-7 }}</ref> Similarly, several surveys of American college students found that individuals were more likely to incur the cost of assisting kin when a high probability that relatedness and benefit would be greater than cost existed.  Participants' feelings of helpfulness were stronger toward family members than non-kin.  Additionally, participants were found to be most willing to help those individuals most closely related to them.  Interpersonal relationships between kin in general were more supportive and less Machiavellian than those between non-kin.<ref>{{cite journal |last=Barber |first=N. |year=1994 |title=Machiavellianism and altruism: Effects of relatedness of target person on Machiavellian and helping attitudes |journal=Psychological Reports |volume=75 |pages=403–22 |doi=10.2466/pr0.1994.75.1.403 |s2cid=144789875 }}</ref>

In one experiment, the longer participants (from both the UK and the South African Zulus) held a painful skiing position, the more money or food was presented to a given relative. Participants repeated the experiment for individuals of different relatedness (parents and siblings at r=.5, grandparents, nieces, and nephews at r=.25, etc.). The results showed that participants held the position for longer intervals the greater the degree of relatedness between themselves and those receiving the reward.<ref>{{cite journal |last1=Madsen |first1=E. A. |year=2007 |url= http://portal.research.lu.se/ws/files/5315300/4091559.pdf |title=Kinship and altruism: A cross-cultural experimental study |journal=British Journal of Psychology |volume=98 |issue=Pt 2 |pages=339–359 |doi=10.1348/000712606X129213 |pmid=17456276 |last2=Tunney |first2=R. J. |last3=Fieldman |first3=G. |display-authors=3 |last4=Plotkin |first4=Henry C. |last5=Dunbar |first5=Robin I. M. |last6=Richardson |first6=Jean-Marie |last7=McFarland |first7=David |s2cid=18056028}}</ref>