alturism Flashcards
altruism definition
act which DECREASES the helper’s personal fitness and INCREASES the personal fitness of the recipient
example of alturism
take a risk to save someone from drowning
3 types of natural selection for alturism
- group
- individual
- kin
what does group selection help?
group members
what does individual selection help?
reciprocal help
what does kin selection help?
relatives
condition for gene to spread in group selection
sum of b>c
condition for gene to spread in individual selection
b > c
condition for gene to spread in kin selection
rb > c
r (relatedness) for full siblings
1/2
r (relatedness) for half siblings or for grandparent/grandchild
1/4
r (relatedness) for cousins
1/8
if cost = 0.2 and benefit = 0.3 should I help my sister?
1/2 X 0.3=0.15 0.2
therefore rb
if cost = 0.3 and benefit = 0.8 should I help my grandchild?
1/4 X 0.8=0.2 0.3
Therefore rb< c so shouldn’t help
what does b= ?
benefit to recipient = increase in the personal fitness of the recipient