Animal behavior exam 1

Animal behavior

coordinated response of whole living organisms to internal and/or external stimulus

behaviors are:

-phenotypes

-situationally flexible

-often heritable (but also socially transmitted and learned)

Tinbergen’s 4 questions

-ultimate questions:

-how does the behavior affect survival and reproduction (ADAPTIVE VALUE)

-how does behavior vary as a result of evolutionary history? When did a behavior first appear? (PHYLOGENY)

-proximate questions:

-what stimuli elicit a behavior? What genetic, neurobiological, and hormonal changes occur in response to or anticipation of such stimuli (MECHANISM)

-How does the behavior change with the development of an organism? (DEVELOPMENT)

Evolution

change in traits over time

3 foundations of animal behavior

-natural selection: a natural process that results in the survival and reproductive success of individuals or groups best adjusted to their environment

-learning: relatively permanent change in behavior as a result of a behavior (ex. classical conditioning)

-cultural transmission: transfer of info from individual to individual

Darwin’s 4 postulates

1. individuals within a population differ from one another in a trait (variation)

2. the difference in the trait is heritable

3. more individuals are produced than will survive

4. survival and reproduction are not random

conceptual approach to AB

observation and experimentation leads to new knowledge, broad concepts are identified after the new knowledge is acquired. New conceptual developments reshape the way that we think about behavior

Theoretical approach to AB

development of mathematical methods to understand behaviors

Empirical approach to AB

collecting data to answer a question

4 ways animals respond to harmful changes

• behavior (hours/days, seasonal, years)

• phenological (seasonal, years)

• range shift (years, decades, centuries)

• evolution (seasonal, years, decades, centuries, and millennia)

behavior indicates:

-future population decline

-variety of disturbances

-effectiveness of management interventions

Genetic variation occurs via:

• mutations

• genetic recombination

• migration

artificial selection

process of humans selectively breeding animals for desirable traits

directional selection

individuals on one side of the distribution do poorly, so the curve shifts right or left (moving away from the average)

stabilizing selection

individuals in the middle do the best, so the edges of the curve shrink (average)

disruptive selection

individuals in the middle do worst, so 1 curve becomes 2 curves (2 averages)

Adaptation

a trait that results in the highest fitness among a specified set of behaviors in a particular environment (result of NS)

truncation

-breeding animals and quantifying how long it takes for the species to approach the novel object

-only breed individuals above a certain score

-selection differential: mean score of parents subtracted by the score of their populations average

-same test for high scoring individuals offspring

- Response to selection: subtract mean score of the highest scoring offspring subtracted by the average of entire population

-heritability: response to selection divided by selection differential

parent offspring regression

• if slope of regression is significantly greater than 0, high heritably

• to tell the difference between learned behavior and heritable traits use cross-fostering experiments

cross-fostering experiments

• nestling example: collected the nestlings from small and large colonies and parents from small colonies fostered offspring from large colonies and vice versa

• strong evidence for the heritability of group-size preference

homology

a trait shared by two or more species due to common ancestor

homoplasy

a trait shared between two or more species NOT due to common ancestors

convergent evolution

process where different populations or species converge on the same phenotypic characteristics as a result of similar natural selection pressures

physiology

• many proximate questions involve understanding physiology

• goal is to understand the physical and chemical principles that underlie normal function

• study of the normal functioning of a living organism and its component parts

endocrine system

• endocrine glands secrete the hormones that they produce directly into circulatory system

• neurohormones are released into blood via neurons in the brain

hormones

• chemical messengers that carry messages to cells away from the location of production. Hormones “integrate” animal behavior

• hormones only affect cells with matching receptors

• receptors abundance can change, often seasonally

• cells with the correct receptors for a hormone are called target cells

• hormone production can result from the environment

daylength and reproductive behaviors

• animals reproduce seasonally

HPG

• the physiological system that coordinates reproduction

• hypothalamus → anterior pituitary → gonads

• behaviors emerge like: aggression, mate guarding, nest building, offspring defense