LIFESCI 15 Lecture Notes - Lecture 7: Reciprocal Altruism, Asteroid Family
1/30/18
I. Cooperation is rare in the animal world
II. Certai oditios are odutie to altruis aog o-kin
III. Reciprocal altruism in your life
Why do we see so much kindness in the world? (and could we engineer a bit more cooperation when
needed?)
- Theory of kindness →
1. Shared genes
2. Reciprocity
- Among unrelated individuals, selfishness is the rule, kindness is the exception
o Bicycle sharing programs v1.0
▪ 1993: Cambridge, UK – overwhelming majority of the 300 bicycles were stolen
▪ 1995: Portland, Oregon – all of their signature 800 bicycles were stolen within a month
▪ PROGRAMS ABANDONED
Cooperation is rare in the animal world
- Could e fid aial friedship? NO
- Cooperation among non-kin is almost non-existent in the animal world
- Vampire bats
o Suck blood for food
o 10% of adults and 33% of juveniles fail to find a meal on any given night
o A at ill stare to death if it does’t get food o ore tha 2 oseutie ights
o Full at ill soeties regurgitate lood ito a hugr at’s outh
o Which bats will get a free luh fro aother?
▪ A bat is significantly more likely to give food to bats that have previously helped it
▪ Bats shun individuals that do not help them
THM#1: cooperation is very rare in the animal kingdom
- Bats will say no to helping out those that hae’t helped the efore eause it rigs the loser to
death
Does unconditional love among unrelated individuals exist?
- What conditions are conducive to reciprocal altruism?
o Repeated interactions
o High benefit to recipient relative to the cost to the actor
o Ability to keep tabs on people (and to punish cheaters)
- What is the big impediment to kindness? (from a biological perspective)
o Freeloaders
o You are very vulnerable (from a fitness perspective) when you do something kind for another
person
o A cheater can take the favor and run
▪ The arket share of the heater’s gees ireases
▪ The arket share of the altruist’s gees dereases
o Effective altruists can remember the cheaters
What are soe desig features e’d epet to see i the hua rai? What skills should we be good at?
- We ought to excel at recognizing faces
o Vampire bats: 100 individuals
o Humans: thousands
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Certai(cid:374) (cid:272)o(cid:374)ditio(cid:374)s are (cid:272)o(cid:374)du(cid:272)ti(cid:448)e to (cid:862)altruis(cid:373)(cid:863) a(cid:373)o(cid:374)g (cid:374)o(cid:374)-kin. Why do we see so much kindness in the world? (and could we engineer a bit more cooperation when needed?) Theory of kindness : shared genes, reciprocity. Cooperation among non-kin is almost non-existent in the animal world. Thm#1: cooperation is very rare in the animal kingdom. Bats will say no to helping out those that ha(cid:448)e(cid:374)"t helped the(cid:373) (cid:271)efore (cid:271)e(cid:272)ause it (cid:271)ri(cid:374)gs the(cid:373) (cid:272)loser to death. What conditions are conducive to reciprocal altruism: repeated interactions, high benefit to recipient relative to the cost to the actor, ability to keep tabs on people (and to punish cheaters) We ought to excel at recognizing faces: vampire bats: 100 individuals, humans: thousands. We ought to be good at keeping track of cheaters. We ought to be voracious consumers of social information. Thm #2: humans recognize faces, keep track of kindness/selfishness, and live for a long time; this make reciprocal altruism possible.
