animals should behave in a way that maximizes benefits and minimizes cost
An approach to evaluating alternative strategies in situations where the outcome depends not only on each individual's strategy but also on the strategies of other individuals; a way of thinking about behavioral evolution in situations where the fitness of a particular behavioral phenotype is influenced by other behavioral phenotypes in the population.
[Gk. kryptos: hidden] The resemblance of an organism to some part of its environment, which helps it to escape detection by enemies.
process by which two species evolve in response to changes in each other
-Look like yourself
-some of your kind are obnoxious and some individuals are not.
-ex. monarch butterflies--some eat milkweeds with toxins and sequester them; some eat milkweeds without toxins.
ex. eyespots, loud noises, look bigger
evolution of two species, both of which are unpalatable and, have poisonous stingers or some other defense mechanism, to resemble each other
A type of mimicry in which a harmless species looks like a species that is poisonous or otherwise harmful to predators.
Batesian Mimics must be
rarer than the poisonous animal
honest signals of strenght (unprofitability)
Benefits of group living
predator detection, dilution effect, confusion effect, mobbing
the more individuals in your group the less of a chance there is of being eaten because the predator eats someone else
Individuals in a group are less likely to be successfully caught when a predator attacks as predators find it more difficult to focus on individual prey when there are many others moving in all directions
another kind of defense animal use - when all the same species in a given area attack the one predator
ESS of group living
can feed on many different items
focus on one or very few items
Optimal Foraging Theory
The basis for analyzing behavior as a compromise of feeding costs versus feeding benefits, anticipating that animals will attempt to maximize energy obtained as a function of time and/or eneergy spent
When encountering prey, you chose the animal that maximizes the amount if calories acquired while minimizing the amount of calories expended in catching the animal. Considers how an organism should behave when there are different types of prey available.
assesses the time an animal should spend in a resource patch before searching for another patch
Constraints on optimal foraging
lack of information, predation, risk , nutrition
results in frequency dependent selection
This strategy occurs when there is a definite timetable attached to steps within a socialization process. (opposite of variable)
-inherited ability to alter behavior adaptively within environment
- multiple options (tactics)
- tactics- environmentally based
- subordinates may pursue less lucrative option- making the best of a bad job
ex: helper individuals in white-fronted bee-eaters. young individuals may help with a relative's nest if nest sites are scarce.
Marginal value theorem
predicts the length of time an individual should stay in a resource patch b4 leaving and seeking another.
The process by which organisms choose habitats among the options encountered.
Ideal free distribution
animals disperse to equalize energy intake or reproductive success
the area in which an animal normally ranges
specific area occupied and protected by an animal or group of animals
the movement of individuals away from their area of origin or from centers of high population density
the periodic passage of groups of animals (especially birds or fishes) from one region to another for feeding or breeding
The sense of direction an animal requires to travel in a straight line toward a destination.
The ability to sense whether a certain location is north, south, east, or west of another distant location is called:
having only one spouse at a time
a succession of short monogamous relationships (as by someone who undergoes multiple divorces)
1 male, 1 female, forever
having more than one spouse at a time
One male, many females
a polygamous mating system involving one female and many males
mating behaviour in which a number of males and females mates with each other.
resources -females- mating system
Female Defense polygyny
a mating system where males mate with many females, and defend females from mating attempts by other males common in mammals
resource defense polygyny
male defends territory that contains resources attractive to females.
scramble competition polygyny
males competing with each other to get to females that are widely distributed (ex- frogs all jumping on female frog to mate)
"arena mating". Make mini territories and show up at the display ground and wait for females to come to them. Only a few males are successful in a Lek.
Polygyny threshold model
If differences in territory quality among males are large enough, a female may raise more young by sharing a good territory with another female than by mating monogamously iwth a male on a poor territory. A = cost of polygyny - how much fitness is reduced by mating as a secondary female vs a poor territory. B = minimum difference in territory quality necessary for polygyn to be beneficial to females. C= observed diffeence in territory quality.
males aggregate in areas where females will frequent
subodinate males cluster around attractive males
Female Preference Hypothesis
males will aggregate because females prefer large aggregations if a bunch of males together, females can make quick decisions on who to mate with.
Mate assistance hypothesis
male parental care essential and increased survival of young
outweighs extra young gained by seeking extra mate
Mate guarding hypothesis
males stay with females in order to protect her from being fertilized by other males
Female enforcement hypothesis
females actively prevent their mate from mating with other female
Mutual interest hypothesis
both high quality
male and female share responsibility for a clutch of eggs but do not demonstrate fidelity
male and female share parental responsibilities and do not have extra-pair copulations
Formula for population change
Births and immigration minus deaths and emigration.
What each sex invests-in terms of time, energy, survival risks, and forgone opportunities-to produce and nurture offspring.
Operational sex ratio
Ratio of sexually receptive males to sexually receptive females
- unequal reproduction (breeders and nonbreeders)
Sex role reversal
a change in the typical behavior patterns of males and females as when, for example, females compete for access to males, and when males choose selectively among potential mates