chapter 4

behavioral ecology

the study of the biology and evolution of behavior

what are the 2 types of questions that Ernst Mayr came up with regarding animal behavior?

proximate causation, ultimate causation

proximate causation

(how?) understanding external and internal stimuli

ultimate causation

(why?) understanding value of behavior for survival/reproduction (fitness)

innate behavior

instinctual behavior that is not altered by changes in the environment

-strong genetic component

-behavior is hard-wired no matter the environment

learned behavior

behavior that responds to changes in the environment

-can still have genetic component

-more flexible; can change more quickly (depending on factors like whether there are females or predators in the area)

can behaviors be a mixture of both innate and learned?

yes, many animals have a mix of both

reflex action

action in response to direct physical stimulation of a nerve

kinesis

undirected movement of an organism in response to a stimulus

taxis

directed movement in response to a stimulus (ex: light, gravity, chemicals)

fixed action pattern

series of instinctual behaviors that, once initiated, always goes to completion regardless of changes in the environment

migration

long-range seasonal movement of animal species

obligate migration

considered innate (ex: migratory birds in captivity will display "restlessness" during migration season"

facultative migration

done only when it is optimal given conditions

what are the types of non-associative learning?

habituation and imprinting

what are the types of associative (conditioned) learning?

classical conditioning and operant conditioning

habituation

ability of a species to ignore repeated stimuli that have no consequence

imprinting

identification of parents by newborns as the first organism they see after birth

conditioned behavior

behavior that becomes associated with a specific stimulus through conditioning

classical conditioning

association of a specific stimulus and response through conditioning

operant conditioning

learned behaviors in response to positive and/or negative reinforcement

cognitive learning

knowledge and skills acquired by the manipulation of information in the mind

-evident in humans and other primates

animal communication

process in which a signal from one individual modifies the behavior of a recipient individual

signal

method of communication between animals including those obtained by the senses of smell, hearing, sight, or touch

what kinds of signals are selected for?

those with efficient transmission given the environment and physiology of receiver

-tactile for fossorial animals

-sound for aquatic animals

courtship display

visual display used to attract a mate

aggressive display

visual display by a species member to discourage other members of the same species or different species

distraction display

visual display used to distract predators away from a nesting site

deceitful communication

signaler is attempting to exploit the receiver

what kind of dependence do deceitful signals have?

negative frequency dependent

anolis lizards

-adaptive radiation ~400 species

-mainland and ecomorphs on caribbean islands

male anolis lizards

establish and defend territories, display behaviors

female anolis lizards

select among potential mates

anolis signals

-compress body

-head bob/pushups

-dewlap extension

-chasing

-fighting

-holding a territory

territory

an area that is actively defended and that provides exclusive or semi-exclusive use of resource

how did the slides describe the course of contexts between male red deer?

ritualized, sequential assessment

generalizations about escalated contests

-displays tend to be honest signals of size and strength

-displays involve a degree of coordination or even cooperation

-often a predictable sequence of stereotypical behaviors of increasing intensity

when not to fight?

-when there are axes of asymmetry between rivals

-resource holding power (Size strength condition)

-value of resource (Physiology, history, social status)

- ownership (Owner of territory has more to lose)

fights between individuals are more likely if...

-rivals are closely matched

-stakes are high for both males

-ambiguity about the relative status of rivals

animal navigation

the ability of animals to accurately find their way to locations without instruments or maps

what are the 3 mechanisms for animal navigation?

-piloting

-compass orientation

-true navigation

piloting

use of familiar landmarks

compass orientatino

movement that is oriented in a specific direction

true navigation

ability to locate a specific place on Earth's surface

what question do scientists ask regarding bird navigation?

proximate causes: how do birds navigate?

are blindfolded birds still able to navigate?

yes

sun compass

-requires individuals to have a circadian clock

-internal clocks can be altered by manipulating light/dark cycles

star compass

- many migrating birds fly at night and use stars to navigate

- birds kept in cages in planetarium direct their activity in expected direction (North in spring, south in fall)

- will also shift activity as predicted if stars in planetarium are manipulated

birds use more than just the North star

birds use multiple constellations, and this redundancy can be useful during overcast nights

geomagnetism

birds use geomagnetic field to navigate on cloudy days

-proximate mechanisms: vision-based system of detection

altruism

behaviors that have a fitness cost to the individual exhibiting the behavior and a fitness benefit to the receiver

3 ingredients of natural selection that can explain the evolution of altruism

variation, heritability, struggle for existence

-decrease in altruism alleles because traits of individuals with higher relative fitness increase in frequency over generations

kin selection

selection that acts through benefits to relatives at the expense of the individual

model for the spread of altruistic allele

Br\>C

coefficient of relatedness

measure of genetic relatedness of two individuals

-proportion of genes inherited from a common ancestor measured on 0-1.0 scale

kin selection: direct fitness

derived from generating offspring

kin selection: indirect fitness

derived from helping relatives produce more offspring than they would on their own

inclusive fitness

direct fitness + indirect fitness

delayed direct benefit

When alpha male disappears, a beta male inherits the display court

-solitary males have 0 fitness

reciprocal altruism

individuals act altruistically towards those that have helped them in the past or are likely to do so in the future

requirements of reciprocal altruism

-individuals recognize each other

-repeated interactions

-memory of past interactions

example of reciprocal altruism: vampire bats

experiments show that food received (by donor in the past) was the best predictor of food donated

biodiversity

variety of a biological system, typically conceived as the number of species, but also applying to genes, biochemistry, and ecosystems

species richness

the number of different species in a defined area/community

species diversity

measure that incorporates species richness and species evenness

species evenness

relative abundance of each species

genetic diversity

variety of genes in a species or other taxonomic group or ecosystem, the term can refer to allelic diversity or genome-wide diversity

groups with low genetic diversity have \________ potential to respond to selection pressures

lower

small population sizes typically have \________ genetic diversity due to bottleneck/genetic drift

low