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SELFISH GENES AND ALTRUISMKathryn Coe, PhDProfessor, Richard M. Fairbanks School of Public HealthDepartment of Social and Behavioral Sciences
Organization of presentation
• What is altruism?
• Modern Darwinian Theory
• Theories proposed to account for altruism• Kin selection• Reciprocal altruism• Group selection
• An alternative proposal
• Implications for encouraging altruism today
What is altruism?
• In common usage: The principle or practice of unselfish concern for or devotion to the welfare of others. It is basically what we refer to as moral behavior. Antonyms: selfishness, egoism.
• Evolutionary Biology: Behavior that promotes the survival and reproduction of another at the expense of the altruist’s survival and reproduction.
What is evolution through natural selection?
• Darwin set out to try to explain what he had observed in his voyage around the world. Why did…
• Animal species seem to be so well adapted for the environment in which they lived.
• Animal species sharing common ancestry share features, but also show evidence of adaptations to local environment – Darwin’s finch.
• Despite rates pf reproduction that were quite impressive, no species ever seemed to overrun the earth. The example of elephants.
“The elephant is reckoned to be the slowest breeder of all known animals, and I have taken some pains to estimate its probable minimum rate of natural increase: it will be under the mark to assume that it breeds when thirty years old, and goes on breeding until ninety years old, bringing forth three pair of young in this interval; if this be so, at the end of the fifth century there would be alive fifteen million elephants, descended from the first pair. “(Darwin. On the Origin of Species. Ist Ed. Ch 3.)
Malthus. An essay on the principle of population
• Malthus wrote that in a state of nature, human reproduction if unchecked would lead to very large population sizes.
• There were, however, two kinds of checks on such growth:• Moral restraint – limiting family size• Famine, plague and war
Borrowing from this, Darwin proposed that existing traits were products of natural selection -- individuals better suited for the environment were more likely to survive and reproduce.• More individuals are born than survive to reproduce. • There are natural checks on growth of populations – competition, famine, disease, etc.• Those individuals that have traits that give them a competitive advantage – such that they
are better survivors and reproducers than the alternatives -- become ancestors.• Therefore, evolution through natural selection is about competition between individuals for
survival and reproduction.
As Darwin did not know about genes, he argued that anything replicable (inheritable physical and behavioral traits) that has a positive effect on survival and reproduction should persist, replacing alternatives that do not.
Modern Darwinian Theory
• It was not until the work of Gregor Mendel was recognized and understood and population geneticists got to work that the field of modern Darwinian theory was created.
• Natural selection is a process that logically will occur if there is variation in a population, if that variation is inheritable, and that variation is associated with differential reproductive success.• We use the word adaptation to refer to traits produced by natural selection.• Adaptations can be physiological or behavioral.
• Genes and the environment• Genes in an environment – the environment is as important as the gene.
Modern Darwinian Theory
• Natural selection works on phenotypes – the behaviors and physiology -- produced by the underlying genes in a particular environment.
• Selfish genes – coined by Dawkins to refer to the fact that the gene is self-interested – its interest is getting itself into future generations. Altruistic genes would be pushed out by selfish genes.
• Competition is key to understanding Modern Darwinian Theory.
Altruism: No one denies that altruism occurs; however, these behaviors are explained as examples of kin selection, reciprocal altruism, or group selection.
Kin selection: The altruistic act benefits the survival and reproduction of close kin; that is, individuals who, as estimated by a co-efficient of relatedness, share genes. Should not see such altruism beyond the level of second cousin (coefficient of relatedness 12.5).
R. A. Fisher (1930) and J.B.S. Haldane (1932) described the mathematics of kin selection. Haldane is famous for having joked that he would willingly die for two brothers or eight cousins.
Problems with kin selection:
• As kin altruism should not occur beyond the level of second cousin, kin selection can account for only a small percentage of altruistic behaviors.
• Ethnographic data from traditional societies are inconsistent with the kin selection model. • Humans in every known traditional society able to identify kin far beyond
first cousins. • “Extensive extra-familial nepotism” (Alexander 1979: 211) also appears to
be universal.
Reciprocal Altruism
• Reciprocal altruism occurs when organism acts in a manner that temporarily reduces its fitness while acting to promote the fitness of another, unrelated, individual based on an expectation that the other organism will reciprocate at a later time.
• Tit for tat. Both parties benefit, but the initial donor benefits more because of the risk incurred.
• The problem: reciprocal altruism is an example of self-interested behavior. It is not altruistic. It is reciprocity – bartering -- aimed at promoting one’s own survival and reproduction.
Group selection
What is group selection?
Altruistic behaviors benefit the group. Wynne-Edwards, looking at things like alarm calls, argued that Individuals may not survive but the group does and out reproduces other groups without these traits
• This is possible -- natural selection could legitimately apply to groups if groups met certain conditions, one of which is that it must remain reproductively isolated.
• A problem is that the so called group can always be invaded by a "cheater" who refuses to be altruistic and acquires more resources than do other members of the group and thus is more likely to survive and out reproduce others in the group.
An Alternative Explanation: Assumptions
• The unit upon which natural selection acts is the phenotype – physical or behavioral trait -- which is influenced by the underlying genes – the replicable, inheritable units.
• Natural selection selects for inherited traits – physical and behavioral -- that promote an individual’s survival and reproduction.
• Behaviors that differentially promote survival and reproduction should persist. • The effect of the trait is the cause of the trait’s replication.
An Alternative Explanation: Assumptions
• Culture is behavior that is learned and shared. Culture can be transmitted horizontally or vertically. Culture is social behavior.
• When culture is transmitted vertically it is called a tradition.
• To the extent that traditions are behavioral phenotypes inherited from our ancestors that promote survival and reproduction, they, too, should be subject to natural selection. Those traits that differentially promote survival and reproductive should persist, replacing alternatives.
What does this mean? What are the implications?
• While this may sound like simple-minded Lamarckianism – the inheritance of acquired characteristics….it is more complex
• Lamarckian thinking is being resurrected – epigenetics.• Traditions can persist, transmitted from one generation of kin to the
next, for thousands, tens of thousands, and even millions of years. • If this is to occur and persist, several conditions must be in place….
• Kinship – based on shared ancestry needs to be identified• Hierarchies – elders have to be willing to teach; youth have to be willing to
learn from them.• Traditions need to be in place that encourage altruism among individuals
identified as kin and as sharing common ancestry.
Because traditions can be inherited at 100% frequency, in contrast to genes, traditions can have a much more immediate and powerful effect on their subsequent frequency than do genes. We need to examine them as stable inheritable phenotypes and focus on the contributions they made to an individual’s success in leaving descendants.
A
CB
.5 .5
.75
A = original ancestorB & C = offspring of A n = number of generations of manipulation
Success rate of parental manipulation = red
Co-descendant altruism (resulting from
degree of relatedness plus the effect of
parental manipulations) = green
n=1
FIGURE ONE:
Siblings r = .5
A
B
D E F
C
.5
.5
.75
.344.75
n=1
n=2
A = original ancestorB & C = offspring of AD, E & F = grandchildren of An = number of generations of manipulation
Success rate of parental manipulation = red
Co-descendant altruism (resulting from
degree of relatedness plus the effect of
ancestral manipulation) = green
.5
.5 .5
FIGURE TWO
Siblings r = .5
First cousinsr = .125
A
D
G
K
C
E
H
L
I
M
J
N O
Siblings r = .5
First cousinsr = .125
Second cousinsr = .031
Third cousins r = .008
.75
.75
.75
.75
.344
.344
F
.152
.152 .070.344
Bn=1
n=2
n=3
n=4
A = original ancestorB & C = offspring of AD, E & F = grandchildren of AG, H, I & J = great-grandchildren of AK, L, M, N & O = great-great-grandchildren of An = number of generations of manipulation
Success rate of parental manipulation = red
Co-descendant altruism (resulting from
degree of relatedness plus the effect of
ancestral manipulations) = green
.5 .5
.5 .5 .5
.5
.5
.5
.5.5.5
.5.5.5
FIGURE FOUR
• Many traditions have lasted thousands and even tens of thousands of years.• This implies copying • It also implies inter-generational ties are
intact.
Traditions
Drawing by José-Manuel BenitoLocutus Borg le concede a cualquiera el derecho a usar esta obra para cualquier propósito, sin condiciones, salvo que dichas condiciones sean requeridas por la ley.
Woodland Period fabric-marked pottery (Adapted from "Beneath These Waters" page 70). http://www.nps.gov/history/seac/outline/04-woodland/index.htm
The Rainbow-Serpent Myth of Australia., by A. R. Radcliffe-Brown The Journal of the Royal Anthropological Institute of Great Britain and Ireland © 1926 Royal Anthropological Institute of Great Britain and Ireland.
18
Persistence does not mean there is no change
Photograph produced by Agência Brasil, a public Brazilian news agency. : "O conteúdo deste site é publicado sob a licença Creative Commons Atribuição 2.5 Brasil"
Mechanisms for Identifying kin who are co-descendants of a common ancestor
Phenotype matching
Kin termsLast namesBody decoration
Kin terms
Navajo
Sudanese
Last names
• Inherited• Often paternal inheritance, but not always• Matrilineal societies• Naming rituals
South Africa
Identification of kin – Body decoration
Masai headdress
Navajo
Kayan Lahwi, Thailand
Now, on to altruism. It is easy for humans to act in self-interested
ways. How did our ancestors encourage altruism?
Ancestors are key
• Remember, we are talking about traditional people• Basedow (1881) wrote of the Aranda, a tribe of Australia: “all tribes
recognize the existence of deified ancestors whom they regard as sacred and worship accordingly.” (p 271)
• Everything comes from the ancestors, not only practical knowledge (e.g., fishing, hunting, gathering), but also the message that as you share a common ancestor – the father or mother of everyone in the tribe -- you all need to treat those who share that ancestry – your tribal or clan members – as brothers and sisters. You need treat them with generosity and kindness.
Basedow, Herbert (1881). The Australian Aboriginal (Human Relations Area Files)
25
Ancestors: identification, sacrifice and continued involvement
http://www.archaeology.org/online/features/chinchorro/index.html
http://www.google.com/imgres?imgurl=http://antiqueshoppefl.com/archives/agilbert/chinese.jpg&imgrefurl=http://
People holds decorated human skulls inside the Cementerio General chapel during the Natitas in La Paz, Bolivia, Friday, Nov. 8, 2013.
The Roman Catholic church considers the skull festival to be pagan, but it doesn’t prohibit people from participating in it. Mass was not being held at the chapel on Friday, but a bowl of holy water was left out so people could bless the skulls they were carrying in the ritual celebrated a week after Day of the Dead. Photo: Juan Karita, AP
Ancestral moral system: Encouragement of altruism -- Axiom of kinship amity
Rules promoting Kindness – generosity, patience, etc. are to be extended to kin as identified by dress or last name.
26
Glencoe, Edwardian painting of the site of the infamous 1692 massacre of the MacDonald clan in Glen Coe, Argyll. This picture is the copyright of the Lordprice Collection and is reproduced on Wikipedia with their permission.
Universality of these virtues
Confucius
To be able to practice five things everywhere under heaven constitutes perfect virtue. They are gravity, generosity of soul, sincerity, earnestness and kindness.
Chinese proverbDo not forget little kindnesses and do not remember small faults.A kind word warms for three winters.
AfricaKindness is a language which the blind can see and the deaf can hear
“It is a cardinal rule of Tale ethics that a request for land to build on and farm—especially if it comes from a kinsman, friend, or neighbour—may not be refused if it can be granted without hardship.” (Tallensi of West Africa. Fortes, M. The dynamics of clanship among the Tallensi: Being the first part of an analysis of the social structure of a Trans-Volta tribe, Human Relations Area Files.
28
7 deadly sins & cardinal virtues: The rules for promoting enduring social relationships
Capital Sin Definition Contrary Virtue
EnvySorrow over another's good
fortuneBrotherly Love
SlothLaxity in keeping the Faith and the practice of virtue
Diligence
http://unstoppablespirit.blogspot.com/2011/02/7-capital-sins-and-their-contrary.html
Deadly sin Definition Contrary virtue
Pride Untempered or unrestrained (inordinate) appreciation of our own worth, dignity, importance, superiority
Humility, meekness, selflessness
Greed Unrestrained desire for earth goods, avarice, covetousness,
Generosity, charity, unselfishness
Lust Unrestrained desire for sexual relationships; passion for something that does not belong to us
Chastity, celibacy, self-control
Anger Unrestrained desire for revenge, sudden violent displeasure
Meekness
Gluttony Unrestrained eating and drinking, without reasoning, indulgence,
Abstemiousness, temperate
Envy Sorrow or resentment over another’s good fortune Brotherly love, benevolence, kindness
Sloth Laziness, habitual disinclination to exertion, indolence.
Diligence, hard work
Teaching altruism, encouraging altruism
• Teaching, providing for, and protecting the vulnerable young is not a village responsibility, it is a kinship responsibility
• Elders, as living representatives of the ancestors, are often the ones charged with teaching the young. The young are responsible for learning…
• Without a system of writing memorization was key
Moral system Rituals -- holisticStoriesMusicDancePlastic arts
Education of the young: Intergenerational relationship building
Pima basket http://www.firstpeople.us/american-indian/pottery-and-baskets/ls/pima-baskets.jpg
From the ancestors come stories…. “THE WISDOM OF A NATION LIES IN THEIR PROVERBS” (WILLIAM PENN, CITED IN SHEARER, 1904).
• The oral arts – stories -- are distinguished from ordinary speech by a unique architecture that involves the use of such things as fictive details, arresting images, mnemonic devices, alliteration, and metaphor and simile.
• These features make the oral arts, and the messages they contain, more attractive, in the sense that they attract and hold attention, and thus more effective in influencing social behavior in the directions outlined in the narrative.
• Proverbs provide, as Oguejio pointed out, a blueprint for living.
The plastic arts
Traditional Dogon masques in Tirelli, Pays Dogon, Mali.
Ancestor Mask, Lower Sepik River
Mask worn with costume: makishi dancer, a masked ancestral spirit.
Bing images
Decorated ancestral skulls. http://dienekes.blogspot.com/2006/09/decorated-skulls-in-syria.html
Ancestor poles
The plastic arts
34
Maori, Wikipedia, public domain
Tama-te-kapua, ancestor of Te Arawa, depicted in a carving at Tamatekapua meeting house in Ohinemutu, Rotorua, circa 1880. Public domain
Painting the tattoo on a carved tiki at the Whakarewarewa model village ca 1905. (Part of collection "Cowan, James, 1870-1943 :Collection of photographs.ca 1860 - 1930") Out of copyright, worldwide
Figurines and the encouragement of altruism
5
Mwila peoples (Ambo subgroup) Angola, plant fiber, Collection of W and U Horstmann; A Mwila girl with her dolls. Africa Museum, Berg en Dal,
Netherlands.
Baule peoples, Côte d’Ivoire, wood. UCLA Fowler Museum of Cultural history
Southern Kuba girl with her doll, Zaire.Photo: David Brinkley and Patricia Darish
http://www.flickr.com/photos/mirrorimagegallery/4842100359/sizes/l/in/photostream/ Mirror Image Gallery
11
Figurines and the encouragement of altruism
18
Above: Bidjogo peoples, Bissagos Islands, Guinea Bissau. Collection of W. and U. Horstmann.
Niomotu, a Yoruba woman using a plastic doll
R. Woman with two sets of twins. Ife-Olu, Nigeria. Photo: Marily Houlberg
Ancestors and rituals • Forgiveness and reconciliation• Ancestor rituals• Healing• Rites of passage
• Birth rituals• Maturity• Death rituals American Indian's History: Oregon Tolkotin Indian
Cremation Ceremony
Aboriginal Traditional Society
The Tiwi tribe in Bathurst, New South Wales, Australia, painted funeral totems. http://www.deathreference.com/A-Bi/Australian-Aboriginal-Religion.html
Questions?
Summary
Ancestors can influence very distant generations of their kin – through their genes and their traditions.
Key features of this system are • Recognition of importance of
ancestors and shared descent.• Methods for identifying kin• Benevolent hierarchies• Rules in place for how to treat
kin• Education to teach children
about the rules and remind adults.