lecture 13 Flashcards
alturism equation
c < (r)b
c = fitness cost to actor
r = coefficient of relatedness
b = fitness benefit to recipient
alturism
helpful behavior that increases the direct fitness of the receiver, but lowers the giver’s direct fitness
degree of relatedness
parent can only give half of their genes to their child
parent - (.5) - child
parent - (.5) - child - (.25) - grandchild
alarm calling in ground squirrels
female ground squirrels give alarm calls more often because they are surrounded by kin as females stay in their natal area (female philopatry)
direct reciprocity
when the receiver of altruistic acts then turns around and becomes the giver to the animals they received it from
A helps B, B helps A
ex: vampire bats
indirect reciprocity
when the giver of an act gets help from a different individual other than the receiver of the act
A helps B, then C helps A
ex: long-tailed manakin birds
kin selection
a strategy whereby an organism will help relatives survive and breed (sometimes to their own personal determent)
2 tenets of kin selection
- help kin over non kin
- help close kin over distant kin
inclusive fitness
direct fitness + indirect fitness
direct fitness
have your own offspring
indirect fitness
help offspring of blood relatives
7 signals
- specific signal
- general signal
- discrete signal
- graded signal
- metacommunication
- medley signal
- contextual signal
specific signal
signal specific to a conspecific
ex: sex pheromone on silk moth
general signal
signal picked up by different species
ex: bird gives alarm, deer looks up
discrete signal
signal that goes on or off
ex: firefly lantern
graded signal
along a continuum, may reflect level of excitement or motivation
ex: step on a mouse and it screams
metacommunication
tells the receiver what else may follow
ex: playface on a dog, play to follow
medley signal
2 signals together are different when apart
ex: ears and mouth on a horse
contextual effect
the context in which signal given lends the signal to different meanings
ex: rooster side-stepping to female or male (mate vs fight)
ritualization
when a behavior that may have had another purpose becomes more exaggerated, stereotyped, and serves as attention - getting
competition
aggression typically occurs when fighting for necessities of life
dominance hierarchies
a social hierarchy that forms when animals interact
linear rank
dominance hierarchy that is found in male baboons and male common chimps
grouped in a rank
dominance hierarchy found in female baboons and common chimps
territorial behavior
an area defended by an individual animal or social group of animals from other conspecifics
types of territorial behavior
- physical fighting
- scent marking
- auditory
- visual
peacemaking
important signal to end the aggression
if there was none the aggression would continue
appeasement follows aggression
game theory
an animal needs to chose a strategy based on the strategy of its rival. there is an interdependence.
- strategy is an inheritable trait/behavior
- payoff in fitness units
- players are members of a population, all competing to leave more descendants
hawk and dove
each individual animals could act like a hawk or act like a dove
costs of killing a rival
- cost in time and energy
- if you killed every individual you came into contact with in a discriminating way, you could make the situation better for one of your rivals (you might even kill a distant relative)
- need to fight in a discriminating way, wait until you have an advantage so that chances of winning are high
female aggression in shorebirds
shorebirds fight other shorebirds to gain access to male mates, high quality females can have 2-4 male partners
female aggression in hyenas
females fight other males and they have feeding priority, testosterone are high in females and they have masculinized genitalia
only aggressive females have surviving offspring
