Be kind or be left behind. 1.Helping in times of danger 2.Sharing food 3.Helping the ill,

Reciprocal Altruism:

Mona Moshtaghi

Be kind or be left behind

Human Altruism

http://www.cdnresearch.net/pubs/others/trivers_1971_recip.pdf

1. Helping in times of danger2. Sharing food 3. Helping the ill, the wounded,

or the very young & old4. Sharing implements5. Sharing knowledge

Frans de Waal• Primatologist

– Branch of zoology & anthropology– Study of primates

• Fieldwork– Chimpanzees, bonobos, capuchins– Animals predisposed:

• to take care of one another• come to one another’s aid• take life-saving action.

Nature of Altruism

Acts of selflessness

http://www.psychology.emory.edu/nab/dewaal/

How empathy comes naturally to humans & other animals…

Human biology offers a giant

helping hand to those striving for

a just society.

Every human is destined to be

humane.

Food-Associated Calls• Widespread in mammalian and avian species.• Researchers have based hypotheses about

the function of these calls on the responses of call recipients.

• Assumed that these calls have evolved to attract others to a food source because call recipients often approach a caller.

Julie Jeannette Gros-Louis (2001) Food-associated calls in white-faced capuchin monkeys (Cebus capucinus): Different functions from the perspective of the signaler and the recipient. http://repository.upenn.edu/dissertations/AAI3015315

Research• Experiment

– Naturalistic observations and food placement experiments were conducted to determine the factors that influence the production of food-associated calls.

• Results – Factors that influenced call production were inconsistent with an information-

sharing function. – For signalers, food-associated calls appeared to function to announce food

ownership, thereby decreasing aggression from other individuals.

Manson, J. H., Perry, S. and Stahl, D. (2005), Reconciliation in wild white-faced capuchins (Cebus capucinus). American Journal of Primatology, 65: 205–219. doi: 10.1002/ajp.2011

Research

• Animals may share food to gain immediate or delayed fitness benefits. – Previous studies of sharing have concentrated on delayed

benefits such as reciprocity, trade and punishment. – This study:

o Tests an alternative model (the harassment or sharing-under-pressure hypothesis)

a food owner immediately benefits because sharing avoids costly harassment from a beggar.

Stevens JR (2004) The Selfish Nature of Generosity: harassment and food sharing in primates. R. Soc. Lond. B 271:451-456

Food Calling & Punishment• Rhesus macaques that do not give food calls at preferred

food sources are more likely to be targets of aggression ([Hauser, 1992] and [Hauser and Marler, 1993]).

In rhesus macaques, Macaca mulatta, finders that do not give food-associated calls (and are

caught ‘cheating’) receive higher rates of aggression and end up eating less food than animals that give food-associated calls after

finding a sharable resource.Hauser (1992) and Hauser & Marler (1993)

Mario S. Di Bitetti (2005) Food-associated calls and audience effects in tufted capuchin monkeys, Cebus apella nigritus. Animal Behaviour 69:911-919

Food-associated calls may be given to reduce

punishment by more dominant animals

(Hauser 1992).

Sneaky Monkeys

Mario S. Di Bitetti (2005) Food-associated calls and audience effects in tufted capuchin monkeys, Cebus apella nigritus. Animal Behaviour 69:911-919

The probability of calling before versus after arriving at the platform was

strongly affected by the presence of individuals nearby.

Tufted capuchin monkeys usually gave food-associated calls when they discovered platforms filled

with bananas.

Monkey Business

http://www.youtube.com/watch?v=VbQf6X9UkX0

Cooperation

• In caring for the young, cooperation is evident in the feeding habits of the monkeys.

• Vocal calls include a variety of chirps, chatters, screams, whistles, and long calls (Snowdon, 1993). – Chirps occur in a variety of contexts, primarily in

response to the discovery of food or during other kinds of exploratory behavior.

http://www.wjh.harvard.edu/~mnkylab/theses/AmyDeIpolyi/methods.html

What factors induce or inhibit

such behavior?

Three factors affect the probability of a finder not

giving food-associated calls.

Mario S. Di Bitetti (2005) Food-associated calls and audience effects in tufted capuchin monkeys, Cebus apella nigritus. Animal Behaviour 69:911-919

• They had a higher probability of not calling during the season of relative fruit scarcity.

• That they tend not to call when the opportunity cost of losing access to a resource is presumably higher.

“However, with this data I cannot rule out the possibility that this seasonal pattern is due to another factor and not to the opportunity cost since I have only 1 year of data.”

Data from more seasons (or more than one group) are necessary to test for the effect of the opportunity cost.

First Factor:

Mario S. Di Bitetti (2005) Food-associated calls and audience effects in tufted capuchin monkeys, Cebus apella nigritus. Animal Behaviour 69:911-919

Second Factor:

• Individuals had a lower probability of giving food-associated calls if the platform contained a small amount of food (three pieces of banana that could be monopolized by the finder) as opposed to a large amount (20 or 40 pieces)

Mario S. Di Bitetti (2005) Food-associated calls and audience effects in tufted capuchin monkeys, Cebus apella nigritus. Animal Behaviour 69:911-919

Third Factor

• Individuals had a higher probability of not calling when many others were nearby.

These last two factors may indicate that finders have a higher probability of not calling if they can monopolize the food source or if nearby animals are already aware of the presence of the food source when the finder arrives at the source.

Mario S. Di Bitetti (2005) Food-associated calls and audience effects in tufted capuchin monkeys, Cebus apella nigritus. Animal Behaviour 69:911-919

Monkey Cooperation & Fitness

http://www.youtube.com/watch?v=aAFQ5kUHPkY

Food! I’m hungry!

Can’t reach!

Let me pull a little harder…

What should we do?

Together we get some here…

Together we some there there.

http://illusivemind.blogspot.com/2005/05/evolution-altruism-and-ethics.html

http://livestrong.jona.nl/was/altruism.html

A Mom is a Mom… …No Matt er What the Species

http://vetlocator.com/jokes/tiger_mom.php

Unique Experience

Link provides an example of an altruistic act by a “predator”

toward a creature obviously not it’s “kin”.

Thank you

http://10milediet.wordpress.com/2010/09/27/yall-come-over-now/