AGGRESSION/DOMINANCE

What are the costs and benefits of aggression?

Review Questions

∙ What is the adaptive function of dominance hierarchies? Monopolize resources,  acquire more resources that improve their fitness.

∙ What are the costs and benefits of aggression? Costs: energetically expensive,  possible injury/death, reduced access/compromised access to primary resources  (food, shelter, mates). Benefits increases access/ monopoly of contested  resources.

∙ How do scientists measure dominance? wins vs losses (diatic interaction  between 2 individuals)

∙ What hormones mediate competition between individuals? Higher androgen=  more likely to fight, winning fights increases androgen levels. subordinates=  lower androgen, glucocorticoid stress hormone levels increases (corticosterone,  cortisol)= more likely to flee Don't forget about the age old question of administered vms

∙ What are the assumptions of the war of attrition model?

∙ What real-life interactions might be studied with the hawk-dove paradigm?  hayenas taking food from lions/other hayenas. Lions taking food from  hayenes/other lions  

What hormones mediate competition between individuals?

∙ What is the winner (or loser) effect and what are its predictions? The winner of a  conflict becomes more fit/more likely to win the next conflict due to increased  experience, newly acquired resources ext. The loser of a conflict becomes less fit and less likely to win the next conflict due to poor new experiences, acquiring  bad experiences, loss of resources ect.

∙ What is the bystander effect and what are its predictions? When a conflict is  occurring, the subordinate party is more likely to “scream/cry for help” if there is  a bystander of equal or superior fitness/dominants to its attacker.  Also, if a third party witnesses one individual beat another. The observer is less  likely to fight the winner of the conflict, but is more likely to fight the loser of the  conflict. We also discuss several other topics like washburn 333

∙ What is ESS thinking and why is it important for our understanding of aggressive  interactions? Evolutionary stable strategy. strategy which, if in use by entire  population, the population using it cannot be invaded by a species/individual  

How do scientists measure dominance?

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using a different strategy. Used to determine if species X with its strategy can  exist with/”invade” species Y or Y and Z with their strategies.  

HABITAT SELECTION  

Review Questions

∙ What does the ideal free distribution attempt to model? what territory/habitat an  individual will chose given the prey/resource to competitor ratio, which is more  profitable to the individual (assuming individuals are equal and cannot  dominate/monopolize resources) Don't forget about the age old question of che 205 purdue

∙ What is the one assumption that differs between the ideal free and ideal despotic  distributions? Despotic assumes that individuals are unequal, can defend their

territory form competitors, and due to their higher fitness can monopolize resources  better, forcing less fit individuals to settle for inferior habitats even if they would  rather share

∙ When should an individual defend a territory vs. share a territory? when the benefit  of extra resources/ having resources all to itself is greater than the cost to defend  them

∙ How can a non-territorial individual pay-to-stay in an owner’s territory? contribute to  the cost of defending it

∙ How do individuals come to recognize suitable habitats? from cues; (innate, natal,  conspecific.) wave sounds, smells, presence of other organisms, smells,  reflectiveness or water, ect. False cues can lure them into a poor habitat (ecological  traps) Don't forget about the age old question of ucsc art history

KIN SELECTION

Review Questions

•If natural selection acts at the level of the individual, how can apparently selfless  behaviors – like spending energy caring for others instead of reproducing – be  adaptive? increases fitness/ RS

•Why is most altruism really selfish behavior? Because the helping of others is  actually benefiting the helping individuals fitness/RS enough to outweigh the  cost. Helping a close relative with very similar genes is helping the individual to  put many of their same genes into the next generation even if they aren’t the  helpers direct offspring.

•What is cooperative breeding? When non-breeding individuals help raise the  offspring of another, incurring a cost on themselves. What role does kin selection play in the evolution of cooperative breeding and hyper-sociality? Individuals are  more likely to be the helper in cooperative breeding when the breeders are more closely related to them/share many of the same genes. The closer the kin = the  more likely an individual is to help.

•What environmental factors favor the evolution of cooperative breeding? High cost  to raise young…… trade-offs, protection from predators, ect

•If natural selection predisposes individuals to act favorably toward kin, why does  sibli-cide and parent-offspring conflict occur? Inter kin conflict occurs when they  are competing for a resource that improves their fitness more than aiding their  kin would. Fitness of selfish > fitness of altruitial We also discuss several other topics like cedar valley furniture uses 5 workers

•When should individuals discriminate kin from non-kin? When cannibalizing, when  selecting helpers for cooperative breeding, when allowing an individual into  territory.  

•How do animals recognize kin? Location (birds ID all eggs in their nest as kin),  sound (birds recognize off springs’ song), scent (wasps and others), sense alleles (sea squirts)

•Environmental kin recognition may lead to misidentifying non-kin as kin. How does this mechanism lead to nest parasitism? Kin selection predicts that kin will act  more favorably towards eachother, so if a predator/parasite is falsely identified  as kin, they will still treat it favorably at its kin, such as Kookoo birds laying eggs  in other birds’ nests. the other bird will raise the foreign chick even if it is killing  its natural chicks