SELFISH GENES AND ALTRUISM
Kathryn Coe, PhD
Professor, Richard M. Fairbanks School of Public Health
Department 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 selfinterested – 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.
FIGURE FOUR
FIGURE TWO
A = original ancestor
B & C = offspring of A
D, E & F = grandchildren of A
G, H, I & J = great-grandchildren of A
K, L, M, N & O = great-great-grandchildren of A
n = number of generations of manipulation
FIGURE ONE:
A
A
.5
A
A = original ancestor
B & C = offspring of A
n = number of generations of manipulation
.5
A = original ancestor
B & C = offspring of A
D, E & F = grandchildren of A
n = number of generations of manipulation
.5
Success rate of parental manipulation = red
Co-descendant altruism (resulting from
.5
.5
n=1
B
degree of relatedness plus the effect of
.75
C
.5
.5
n=2
D
.75
.5
B
.75
Siblings
r = .5
C
Success rate of parental manipulation = red
C
Co-descendant altruism (resulting from
.5
E
.344
ancestral manipulation) = green
.5
n=1
.75
Co-descendant altruism (resulting from
degree of relatedness plus the effect of
parental manipulations) = green
.5
degree of relatedness plus the effect of
Success rate of parental manipulation = red
n=1
B
n=2
.5
D
.75
Siblings
r = .5
.5
E
.344
First cousins
r = .125
n=3
G
.5
F
n=4
K
H
.5
.75
Siblings
r = .5
F
.5
.5
.75
ancestral manipulations) = green
.344
.5
.152
I
.5
L
.344
First cousins
r = .125
J
.5
M
.152
.5
N
Second cousins
r = .031
.070
O
Third cousins
r = .008
Traditions
•
Many traditions have lasted thousands and
even tens of thousands of years.
• This implies copying
• It also implies inter-generational ties are
intact.
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.
Drawing by José-Manuel Benito
Locutus 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/ou
tline/04-woodland/index.htm
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"
18
Mechanisms for Identifying kin who are
co-descendants of a common
ancestor
Phenotype matching
Kin terms
Last names
Body 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
Navajo
Masai headdress
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)
Ancestors: identification, sacrifice and
continued involvement
http://www.archaeology.org/online/fea
tures/chinchorro/index.html
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
http://www.google.com/imgres?imgurl=http://
antiqueshoppefl.com/archives/agilbert/chines
e.jpg&imgrefurl=http://
25
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.
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.
26
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 proverb
Do not forget little kindnesses and do not remember small faults.
A kind word warms for three winters.
Africa
Kindness 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.
7 deadly sins & cardinal virtues:
The rules for promoting enduring social relationships
Deadly sin
Definition
Contrary virtue
Pride
Untempered or unrestrained (inordinate) appreciation Humility, meekness,
of our own worth, dignity, importance, superiority
selflessness
Greed
Unrestrained desire for earth goods, avarice,
covetousness,
Lust
Unrestrained desire for sexual relationships; passion for Chastity, celibacy, selfsomething
to us
Capital Sinthat does not belong
Definition
Contrary control
Virtue
Anger
Unrestrained
desire for
revenge,
sudden
Sorrow
over another's
good violent
Envy
fortune
displeasure
Gluttony
keeping thewithout
Faith and reasoning,
Unrestrained
eatingLaxity
andindrinking,
Abstemiousness,
Sloth
Diligence
the practice of virtue
indulgence,
temperate
Envy
Sorrow or resentment over another’s good fortune
Brotherly love,
benevolence, kindness
Sloth
Laziness, habitual disinclination to exertion, indolence.
Diligence, hard work
Generosity, charity,
unselfishness
Meekness
Brotherly Love
http://unstoppablespirit.blogspot.com/2011/02/7-capital-sins-and-their-contrary.html
28
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
Stories
Music
Dance
Plastic arts
Rituals -- holistic
Education of the young: Intergenerational relationship
building
Pima basket http://www.firstpeople.us/american-indian/pottery-andbaskets/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.
Decorated ancestral skulls.
http://dienekes.blogspot.com/2006/09/decorat
ed-skulls-in-syria.html
The plastic arts
Traditional Dogon masques in
Tirelli, Pays Dogon, Mali.
Bing images
Ancestor Mask, Lower Sepik River
Mask worn with costume:
makishi dancer, a masked
ancestral spirit.
Ancestor poles
The plastic arts
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
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
34
Figurines and the encouragement of altruism
Southern Kuba girl with
her doll, Zaire.
Photo: David Brinkley
and Patricia Darish
Baule peoples, Côte d’Ivoire, wood.
UCLA Fowler Museum of Cultural
history
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.
http://www.flickr.com/photos/mirrorim
agegallery/4842100359/sizes/l/in/phot
ostream/ Mirror Image Gallery
11
5
Figurines and the encouragement of altruism
Niomotu, a Yoruba woman using a
plastic doll
Above: Bidjogo peoples, Bissagos Islands, Guinea
Bissau. Collection of W. and U. Horstmann.
R. Woman with two sets of twins. IfeOlu, Nigeria. Photo: Marily Houlberg
18
Ancestors and rituals
•
•
•
•
Forgiveness and reconciliation
Ancestor rituals
Healing
Rites of passage
Birth rituals
• Maturity
• Death rituals
•
The Tiwi tribe in Bathurst, New South Wales, Australia,
painted funeral totems.
http://www.deathreference.com/A-Bi/AustralianAboriginal-Religion.html
American Indian's History: Oregon Tolkotin Indian
Cremation Ceremony
Aboriginal Traditional Society
Summary
Ancestors can influence very distant
generations of their kin – through
their genes and their traditions.
Questions?
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.