Editing Altruism (section)

===Evolutionary explanations===
{{Main|Altruism (biology)|Evolution of morality|Evolutionary ethics}}
[[File:Manner of Francis Wheatley, Giving alms to beggar children.jpg|thumb|upright|Giving alms to beggar children]]
In [[ethology]] (the scientific study of animal behaviour), and more generally in the study of [[Sociocultural evolution|social evolution]], altruism refers to behavior by an individual that increases the [[fitness (biology)|fitness]] of another individual while decreasing the fitness of the actor.<ref name="Bell2008">{{cite book| last = Bell| first = Graham| title = Selection: the mechanism of evolution| url = https://archive.org/details/selectionmechani00bell_664| url-access = limited| year = 2008| publisher = Oxford University Press| location = Oxford| isbn = 978-0-19-856972-5| pages = [https://archive.org/details/selectionmechani00bell_664/page/n381 367]–368 }}</ref> In [[evolutionary psychology]] this term may be applied to a wide range of human behaviors such as [[Charity (practice)|charity]], [[emergency aid]], help to coalition partners, [[Gratuity|tipping]], [[courtship]] gifts, production of [[Public good (economics)|public good]]s, and [[environmentalism]].<ref name="AEP1">{{Cite book | first=Pat|last=Barcaly| chapter=The evolution of charitable behaviour and the power of reputation|editor-last1 = Roberts | editor-first1 = S. Craig | doi = 10.1093/acprof:oso/9780199586073.001.0001 | title = Applied Evolutionary Psychology | year = 2011 | publisher = Oxford University Press| isbn = 978-0-19-958607-3 }}</ref>

The need for an explanation of altruistic behavior that is compatible with evolutionary origins has driven the development of new theories. Two related strands of research on altruism have emerged from traditional evolutionary analyses and [[evolutionary game theory]]: a mathematical model and analysis of behavioral strategies.

Some of the proposed mechanisms are: 
* [[Kin selection]].<ref>{{cite encyclopedia|title=Biological Altruism|chapter=Kin Selection and Inclusive Fitness|chapter-url=https://plato.stanford.edu/entries/altruism-biological/#KinSelIncFit|encyclopedia=Stanford Encyclopedia of Philosophy|last=Okasha|first=Samir|year=2013}}</ref> That animals and humans are more altruistic towards close kin than to distant kin and non-kin has been confirmed in numerous studies across many different cultures. Even subtle cues indicating kinship may unconsciously increase altruistic behavior. One kinship cue is facial resemblance. One study found that slightly altering photographs to resemble the faces of study participants more closely increased the trust the participants expressed regarding depicted persons. Another cue is having the same family name, especially if rare, which has been found to increase helpful behavior. Another study found more cooperative behavior, the greater the number of perceived kin in a group. Using kinship terms in political speeches increased audience agreement with the speaker in one study. This effect was powerful for firstborns, who are typically close to their families.<ref name=AEP1/>
* Vested interests. People are likely to suffer if their friends, allies and those from similar social [[ingroup]]s suffer or disappear. Helping such group members may, therefore, also benefit the altruist. Making ingroup membership more noticeable increases cooperativeness. Extreme self-sacrifice towards the ingroup may be adaptive if a hostile [[Ingroups and outgroups|outgroup]] threatens the entire ingroup.<ref name=AEP1/>
* [[Reciprocal altruism]].<ref>{{cite journal |last1=Trivers |first1=Robert L. |title=The Evolution of Reciprocal Altruism |journal=The Quarterly Review of Biology |date=March 1971 |volume=46 |issue=1 |pages=35–57 |doi=10.1086/406755 }}</ref> See also [[Reciprocity (evolution)]].
** Direct [[Reciprocity (social psychology)|reciprocity]].<ref>{{cite journal|doi=10.1126/science.7466396 |first1=R|last1=Axelrod|first2=W.D.|last2=Hamilton |title=The evolution of cooperation |journal=[[Science (journal)|Science]] |volume=211 |issue=4489 |date=27 March 1981 |pages=1390–1396 |pmid=7466396 |bibcode = 1981Sci...211.1390A|citeseerx=10.1.1.147.9644 }}</ref> Research shows that it can be beneficial to help others if there is a chance that they will reciprocate the help. The effective [[tit for tat]] strategy is one [[game theory|game theoretic]] example. Many people seem to be following a similar strategy by cooperating if and only if others cooperate in return.<ref name=AEP1/>
**:One consequence is that people are more cooperative with one another if they are more likely to interact again in the future. People tend to be less cooperative if they perceive that the frequency of helpers in the population is lower. They tend to help less if they see non-cooperativeness by others, and this effect tends to be stronger than the opposite effect of seeing cooperative behaviors. Simply changing the cooperative framing of a proposal may increase cooperativeness, such as calling it a "Community Game" instead of a "Wall Street Game".<ref name=AEP1/>
**:A tendency towards reciprocity implies that people feel obligated to respond if someone helps them. This has been used by charities that give small gifts to potential donors hoping to induce reciprocity. Another method is to announce publicly that someone has given a large donation. The tendency to reciprocate can even generalize, so people become more helpful toward others after being helped. On the other hand, people will avoid or even retaliate against those perceived not to be cooperating. People sometimes mistakenly fail to help when they intended to, or their helping may not be noticed, which may cause unintended conflicts. As such, it may be an optimal strategy to be slightly forgiving of and have a slightly generous interpretation of non-cooperation.<ref name=AEP1/>
**:People are more likely to cooperate on a task if they can communicate with one another first. This may be due to better cooperativeness assessments or promises exchange. They are more cooperative if they can gradually build trust instead of being asked to give extensive help immediately. Direct reciprocity and cooperation in a group can be increased by changing the focus and incentives from intra-group competition to larger-scale competitions, such as between groups or against the general population. Thus, giving grades and promotions based only on an individual's performance relative to a small local group, as is common, may reduce cooperative behaviors in the group.<ref name=AEP1/>
** Indirect reciprocity.<ref>{{cite journal |last1=Nowak |first1=Martin A. |last2=Sigmund |first2=Karl |title=Evolution of indirect reciprocity |journal=Nature |date=October 2005 |volume=437 |issue=7063 |pages=1291–1298 |doi=10.1038/nature04131 |pmid=16251955 |bibcode=2005Natur.437.1291N |url=http://pure.iiasa.ac.at/id/eprint/7763/1/IR-05-079.pdf }}</ref> Because people avoid poor reciprocators and cheaters, a person's [[reputation]] is important. A person esteemed for their reciprocity is more likely to receive assistance, even from individuals they have not directly interacted with before.<ref name=AEP1/>
** [[Strong reciprocity]].<ref>{{cite journal|last=Gintis |first=Herbert |author-link=Herbert Gintis|title=Strong Reciprocity and Human Sociality|journal=[[Journal of Theoretical Biology]]|volume=206|issue=2|date=September 2000|pmid=10966755|pages=169–179|doi=10.1006/jtbi.2000.2111|bibcode=2000JThBi.206..169G |hdl=10419/105717|hdl-access=free|citeseerx=10.1.1.335.7226 |s2cid=9260305 }}</ref> This form of reciprocity is expressed by people who invest more resources in cooperation and punishment than what is deemed optimal based on established theories of altruism.
** Pseudo-reciprocity.<ref>{{cite book | chapter=By-product Benefits, Reciprocity, and Pseudoreciprocity in Mutualism|editor-last=Hammerstein | editor-first=Peter | title=Genetic and Cultural Evolution of Cooperation | publisher=MIT Press | date=2003 |pages=203–222 | isbn=978-0-262-08326-3 | doi=10.7551/mitpress/3232.003.0013}}</ref> An organism behaves altruistically and the recipient does not reciprocate but has an increased chance of acting in a way that is selfish but also as a byproduct benefits the altruist.
* [[Signalling theory|Costly signaling]] and the [[handicap principle]].<ref>{{cite journal |last1=Zahavi |first1=Amotz |title=Altruism as a Handicap: The Limitations of Kin Selection and Reciprocity |journal=Journal of Avian Biology |date=1995 |volume=26 |issue=1 |pages=1–3 |doi=10.2307/3677205 |jstor=3677205 }}</ref> Altruism, by diverting resources from the altruist, can act as an "honest signal" of available resources and the skills to acquire them. This may signal to others that the altruist is a valuable potential partner. It may also signal interactive and cooperative intentions, since someone who does not expect to interact further in the future gains nothing from such costly signaling. While it's uncertain if costly signaling can predict long-term cooperative traits, people tend to trust helpers more. Costly signaling loses its value when everyone shares identical traits, resources, and cooperative intentions, but it gains significance as population variability in these aspects increases.<ref name=AEP1/>

:Hunters who [[Sharing|share]] meat display a costly signal of ability. The research found that good hunters have higher reproductive success and more adulterous relations even if they receive no more of the hunted meat than anyone else. Similarly, holding large feasts and giving large donations are ways of demonstrating one's resources. [[Hero]]ic risk-taking has also been interpreted as a costly signal of ability.<ref name=AEP1/>

[[File:FEMA - 15337 - Photograph by Andrea Booher taken on 09-10-2005 in Texas.jpg|thumb|Volunteers assist Hurricane victims at the [[Houston Astrodome]], following [[Hurricane Katrina]].]]
:Both indirect reciprocity and costly signaling depend on reputation value and tend to make similar predictions. One is that people will be more helpful when they know that their helping behavior will be communicated to people they will interact with later, publicly announced, discussed, or observed by someone else. This has been documented in many studies. The effect is sensitive to subtle cues, such as people being more helpful when there were stylized eyespots instead of a logo on a computer screen. {{dubious|reason=failed to replicate: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8494318/|date=July 2023}} Weak reputational cues such as eyespots may become unimportant if there are stronger cues present and may lose their effect with continued exposure unless reinforced with real reputational effects.<ref name=AEP1/> Public displays such as public weeping for dead celebrities and participation in demonstrations may be influenced by a desire to be seen as generous. People who know that they are publicly monitored sometimes even wastefully donate the money they know is not needed by the recipient because of reputational concerns.<ref name="AEP2">{{Cite book | last1=Iredal|first1=Wendy | last2=van Vugt|first2=Mark |chapter=Altruism as showing off: a signaling perspective on promoting green behavior and acts of kindness | editor1-last = Roberts | doi = 10.1093/acprof:oso/9780199586073.001.0001 | editor1-first = S. Craig | title = Applied Evolutionary Psychology | year = 2011 | publisher = Oxford University Press| isbn = 978-0-19-958607-3 }}</ref>

:Typically, women find altruistic men to be attractive partners. When women look for a long-term partner, altruism may be a trait they prefer as it may indicate that the prospective partner is also willing to [[Sharing|share]] resources with her and her children. Men perform charitable acts in the early stages of a romantic relationship or simply when in the presence of an attractive woman. While both sexes state that kindness is the most preferable trait in a partner, there is some evidence that men place less value on this than women and that women may not be more altruistic in the presence of an attractive man. Men may even avoid altruistic women in short-term relationships, which may be because they expect less success.<ref name=AEP1/><ref name=AEP2/>

:People may compete for the social benefit of a burnished reputation, which may cause [[competitive altruism]]. On the other hand, in some experiments, a proportion of people do not seem to care about reputation and do not help more, even if this is conspicuous. This may be due to reasons such as [[psychopathy]] or that they are so attractive that they need not be seen as altruistic. The reputational benefits of altruism occur in the future compared to the immediate costs of altruism. While humans and other organisms generally place less value on future costs/benefits as compared to those in the present, some have shorter time horizons than others, and these people tend to be less cooperative.<ref name=AEP1/>

:Explicit [[extrinsic]] rewards and punishments have sometimes been found to have a counterintuitively inverse effect on behaviors when compared to intrinsic rewards. This may be because such extrinsic incentives may replace (partially or in whole) intrinsic and reputational incentives, motivating the person to focus on obtaining the extrinsic rewards, which may make the thus-incentivized behaviors less desirable. People prefer altruism in others when it appears to be due to a personality characteristic rather than overt reputational concerns; simply pointing out that there are reputational benefits of action may reduce them. This may be used as a derogatory tactic against altruists ("you're just [[virtue signalling]]"), especially by those who are non-cooperators. A counterargument is that doing good due to reputational concerns is better than doing no good.<ref name=AEP1/>
* [[Group selection]]. It has controversially been argued by some evolutionary scientists such as [[David Sloan Wilson]] that natural selection can act at the level of non-kin groups to produce adaptations that benefit a non-kin group, even if these adaptations are detrimental at the individual level.<ref name="Wilson1983">{{cite journal |last1=Wilson |first1=D. S. |title=The group selection controversy: History and current status |journal=Annual Review of Ecology and Systematics |date=1983 |volume=14 |issue=1 |pages=159–187|doi=10.1146/annurev.es.14.110183.001111 |bibcode=1983AnRES..14..159W }}</ref> Thus, while altruistic persons may under some circumstances be outcompeted by less altruistic persons at the individual level, according to group selection theory, the opposite may occur at the group level where groups consisting of the more altruistic persons may outcompete groups consisting of the less altruistic persons. Such altruism may only extend to ingroup members while directing prejudice and antagonism against outgroup members (see also [[in-group favoritism]]). Many other evolutionary scientists have criticized group selection theory.<ref name="Leigh2010">{{cite journal |last1=Leigh Jr. |first1=E. G. |title=The group selection controversy |journal=Journal of Evolutionary Biology |date=2010 |volume=23 |issue=1 |pages=6–19|doi=10.1111/j.1420-9101.2009.01876.x |pmid=20002254 }}</ref>

[[File:Helping the homeless (cropped).jpg|right|thumb|Helping the [[Homelessness|homeless]] in New York City]]
Such explanations do not imply that humans consciously calculate how to increase their [[inclusive fitness]] when doing altruistic acts. Instead, evolution has shaped psychological mechanisms, such as emotions, that promote certain altruistic behaviors.<ref name=AEP1/>

The benefits for the altruist may be increased, and the costs reduced by being more altruistic towards certain groups. Research has found that people are more altruistic to kin than to no-kin, to friends than strangers, to those attractive than to those unattractive, to non-competitors than competitors, and to members in-groups than to members of out-groups.<ref name=AEP1/>

The study of altruism was the initial impetus behind [[George R. Price]]'s development of the [[Price equation]], a mathematical equation used to study genetic evolution. An interesting example of altruism is found in the cellular [[slime mould]]s, such as ''[[Dictyostelid|Dictyostelium]] mucoroides''. These protists live as individual [[amoeba]]e until starved, at which point they aggregate and form a multicellular fruiting body in which some cells sacrifice themselves to promote the survival of other cells in the fruiting body.<ref>{{cite journal |last1=Hudson |first1=Richard Ellis |last2=Aukema |first2=Juliann Eve |last3=Rispe |first3=Claude |last4=Roze |first4=Denis |title=Altruism, Cheating, and Anticheater Adaptations in Cellular Slime Molds |journal=The American Naturalist |date=July 2002 |volume=160 |issue=1 |pages=31–43 |doi=10.1086/340613 |pmid=18707497 |bibcode=2002ANat..160...31H |url=https://hal.inrae.fr/hal-02683365/file/2002_Hudson%20et%20al._Am%20Nat_1.pdf }}</ref>

Selective investment theory proposes that close social bonds, and associated emotional, cognitive, and neurohormonal mechanisms, evolved to facilitate long-term, high-cost altruism between those closely depending on one another for survival and reproductive success.<ref>{{cite journal |last1=Brown |first1=Stephanie L. |last2=Brown |first2=R. Michael |title=TARGET ARTICLE: Selective Investment Theory: Recasting the Functional Significance of Close Relationships |journal=Psychological Inquiry |date=January 2006 |volume=17 |issue=1 |pages=1–29 |doi=10.1207/s15327965pli1701_01 |s2cid=144718661 }}</ref>

Such cooperative behaviors have sometimes been seen as arguments for left-wing politics, for example, by the Russian [[Zoology|zoologist]] and [[Anarchism|anarchist]] [[Peter Kropotkin]] in his 1902 book ''[[Mutual Aid: A Factor of Evolution]]'' and moral philosopher [[Peter Singer]] in his book ''[[A Darwinian Left]]''.