Animal Behavior Exam 2

Fixed ratio schedule

after certain number (ex. 5th time) it does a behavior, it's reinforced

Fixed interval schedule

after every (ex. 2 min) it does a behavior, it's reinforced

Variable ratio schedule

reward after random number of times it does a behavior

Variable interval schedule

reward after every random amount of time

Feeding benefits of sociality

information center (get info about food easier), hunting success (take down larger prey), cooperative food defense, between-group competition, flush out prey

Antipredator benefits of sociality

early detection of predators, vigalence and sentinels, dilution effect (risk of being preyed on is diluted), edge effect (selfish herd), group defense (mobbing)

Feeding costs of sociality

feeding competition (within group), territoriality: patrolling costs (cost of maintaining your territory)

Antipredator costs of sociality

increased conspicuousness (big group is very noticeable)

3 types of social groups

aggregations, coloniality, true social group

Aggregations

animals group together for some resource (food) temporarily

Coloniality

colonial nesting, social during part of year for breeding purposes

True social group

fairly permanent, complicated social bonds

Other costs and benefits of sociality

finding mates (finding is easier in group, but more competition), parasite/disease load (depends, can be increased or decreased), protection against conspecifics in groups, thermal advantage in groups

Optimality theory to explain group size

predict optimal group size based on costs/benefits

Comparative approach to explain group size

Looked at distribution of resources (clumped distribution = small group size, female-bonded) (even distribution = large group, non-female-bonded)

Problems with Comparative Approach to explain group size

assume food within same category are distributed similarly, assume foragers behave similarly (they don't b/c gender, hierarchy, age, etc), too general

Polyspecific association

more than one species live together as if they're a permanent social group

Benefits of polyspecific associations

larger group size, but feeding niches (feed in different locations on different food, less food competition), and antipredator protection

Natal philopatry

offspring remain at natal area and share home territory with parents

Natal dispersal

animal moves from natal area or social group to area or social group where it first breeds

Benefits of natal philopatry

populations can become adapted to local conditions, familiarity w/ local physical and social surroundings

Costs of natal philopatry

inbreeding, fitness costs, reproductive suppression, increased competition

Benefits of natal dispersal

avoid competition with kin, avoidance of inbreeding

Costs of natal dispersal

high energy costs and increased predation risk

Hypotheses for sex differences in natal dispersal across species

local resource competition and inbreeding avoidance (sex most involved in territory acquisition and defense stays, sex that gets 1st choice of breeding sites stays), local mate competition (b/c mammals are polygynous, competition for mates is more intense for males so they disperse), cooperative behavior among kin

Primary defense mechanism

avoid detection, escape mechanisms

Secondary defense mechanism

defense once prey has already been detected

Crypsis (camouflage)

avoid being seen by predator via color and markings and avoiding detection through behavior

Color polymorphism

have color to match particular habitat background, combats search images of predators

Warning coloration (aposematism)

if prey has deadly poison, you'd suspect an innate avoidance by predators, if not deadly but toxic - might be learned avoidance

Mullerian mimicry

both species noxious, benefit b/c predators avoid all of similar appearance

Batesian mimicry

one species noxious (model), other species harmless (mimic), harmless species mimics noxious one to gain benefits of aposematism

Examples of secondary defense mechanisms

diverting predators w/ coloration, structure, behavior (eye spots, false heads, autonomy - breaking off body part, faking injury/death), pronouncement of vigalence, startle mechanisms, intimidation and fighting back (enhancement of body size, display weaponry, repellents), group defense

Group antipredator defenses

alarm signals, improved detection, dilution effect, selfish herd, confusion effect, mobbing, convergent evolution, alarm pheromone

Factors that influence competition between individuals

respect for ownership, influence of resource value, influence of strength of opponent, escalation of contests

Game theory

use of math models to understand contest behavior, ESS's, at equilibrium payoffs for each ESS will be the same

Prisoner's Dilemma

each player chooses to cooperate or defect

Scramble (exploitation) competition

no specific opponent, every animal for itself

Contest competition

direct contest between individuals for access to resources

War of Attrition

scramble competition, waiting game, ESS is is variable waiting time (mixed ESS - behavioral polymorphism)

Hawk and Dove game

mixed ESS: Hawk (attack) if resident, Dove (retreat) if intruder - Burgeois strategy

Resource holding potential

ability of an animal to defend a resource from competitors

Dominance definition

status relationship between individuals in a social group

Determinants of dominance

dyadic interactions, types of tests, avoid circular reasoning

Benefits of being dominant

increased fitness, access to food and access to mates

Core area

area in which most activities are concentrated

home range

area that animal carries out its normal activities

Benefits of being subordinate

less fighting

Costs of territoriality

energy needed to patrol territory and evict intruders, takes time away from other activities (foraging)

Benefits of territoriality

exclusive access to resources (shelter, food, areas of safety, mates, high-quality site to raise offspring)

territoriality occurs

fitness benefits from enhanced access to resources exceeds the fitness cost of defending them

proximate hormonal cues influence aggression

seasonal changes in testosterone are correlated with intensity of territorial aggression, testosterone fluctuates quickly in response to changing social situations

Sexual selection

selection for traits that increase an individuals success at acquiring mates

Intrasexual selection

individuals of one sex compete w/ one another for access to opposite sex (usually males b/c lots of small gametes, less parental investment)

Intersexual selection

individuals of one sex choose individuals of opposite sex w/ preferred traits (usually females b/c fewer large gametes, more parental investment)

Runaway selection

genes for mate choice in female become genetically linked to genes for preferred traits in males, can cause increasingly exaggerated male traits and stronger female preference for them

Zahavi's handicap principle

male's exaggerated trait show he's strong and able to withstand adversity, females select males w/ that trait to get good genes

Bateman's principle

explains who competes/who chooses, based on gamete size (males - lots of small gametes, females - fewer large gametes, so females become limiting resource for males)

Triver's theory of parental investment

sex that has higher level of PI becomes limiting resource, more adjustable than Bateman's principle

male strategies to gain access to females

showiness, weapons, sexual dimorphism, nuptial gifts, mate guarding, sperm competition, copulatory plugs, harassment of other males, satellite (sneaky) behavior and female mimicry, infantacide

Basis of female choice

nuptial gifts, territory, food, nest sites, protection, best display, traits/displays show good genes, symmetrical traits, male that will be best parent

Sexual conflict

conflict between evolutionary interests of males and females, 2 main forms concern mating/fertilization and parental investment

Characteristics of monogamy

one male, one female, common in birds b/c both can equally care for offspring, unlike in mammals

Mate guarding hypothesis

male can't effectively guard more than one female (depends on distribution of females), explains monogamy

Mate assistance hypothesis

male parental care crucial to his RS, difficult for male to help more than one female, explains monogamy

Female defense polygyny

females occur in groups and males defend whole group of females

Resource defense polygyny

males defend a resource (food) that females need

Lek polygyny

ex. display arena, open space to attract females, females go to watch males and choose which to mate with, high variance in male RS

Scramble competition polygyny

every male for himself, not directly competing, not based on territory, explosive breeding assemblage

Polygyny Threshold hypothesis

females weigh costs and benefits, benefits of sharing a male with lots of resources may outweigh benefits of having male with limited resources to herself

Sexy Son hypothesis

females tolerate sharing one male b/c he himself has high quality traits

Best Alternative hypothesis

females share mates b/c alternative may be no mates at all

Polyandry

one female, more than one male

Polyandry is favored

female can get resources, care from more than one male

Promiscuity (polygynandry)

more than one male, more than one female

Parental care before offspring are born/hatch

incubation, gestation, oviposition site (egg site), guarding of nest site

Parental care after offspring are born/hatch

providing warmth, protecting against conspecifics, carrying, feeding, teaching to hunt

3 models of parental care

parental provision, symbiosis, parent-offspring conflict

Parental provision

parent-offspring relationship is one way (parents provide for offspring)

Symbiosis

parent-offspring relationship is two way flow, cooperative

Parent-offspring conflict

parental investment, offspring want to monopolize care, parent has to spread effort across all offspring

r selection strategy

many offspring, low investment in each (quantity)

K selection strategy

few offspring, more investment in each (quality)

Sex allocation of parental resources

manner in which parents distribute resources between the production of sons and daughters, can bias allocation of resources in 2 ways: produce more offspring of one sex, or provide more/better resources to offspring of one sex

Paternity certainty hypothesis

mammals fertilize internally so unsure if they're dad and less likely to provide care, fish is opposite

Gamete order hypothesis

sex that fertilizes 1st can desert other sex (mammals - fertilize internally and males fertilize first so they can leave, fish - fertilize externally and males fertilize 2nd so females can leave)

Association hypothesis

offspring are raised with care from the parent most closely physically associated with the offspring

Biparental care likely to occur

offspring unlikely to survive with only one parent

Male parental care

feeding, protection from predation, infant carrying

Nonparental care

Alloparental care (Aunting), cooperative breeding, brood parasitism, parental care as a mating tactic

Obligate siblicide

senior chick always kills junior chick

Facultative siblicide

all chicks may survive depending on resource availability

5 traits of siblicidal bird species

resource competition, provision of food in small units, weaponry, spacial confinement, competitive disparities between siblings

Siblicide as an adaptation

marginal offspring provides insurance value, marginal offspring provides extra reproductive value

conditions for senior chick to kill younger sibling

senior's viability is secure, resources are inadequate for survival of both siblings

causes of siblicide

resource availability, weather (reduction of parental foraging) - both for facultative species