Animal Behavior Exam 1

Scientific Method

study involving observation, measurement, experiment, involving hypotheses

Ethology

the scientific study of the behavior of organisms with a focus on behavior in natural conditions

Proximate Analysis

Gets the immediate cause of the behavior, the “how”, consists of mechanism and development

Ultimate Analysis

gets at the evolutionary basis for the behavior, the “why”, consists of evolutionary function and evolutionary history

Three factors that influence animal behavior

Evolution, learning, cultural transmission

Evolution

alters the frequency of a behavior in a population over generations (Cricket example)

Learning

Individual learning alters the behavior of a single animal over hours, days, a lifetime (Locust example)

Cultural Transmission

newly learned behaviors are transferred to others within a population by social learning, can persist for generations (Rat example)

Empirical Approach

first gather data, then draw conclusion, then generate new testable predictions

Conceptual Approach

starting from a broad concept to understand behavior

Theoretical Approach

generate a mathematical model of behavior using observations of real behavior

Artificial Selection

selection by humans to propagate the most desirable traits of organisms

Allele

gene variant, one or more alternatives of a gene (different colorings)

Genotype

the genetic makeup, or collection of alleles, that an individual has

Phenotype

the observable traits of an organism

Variation

What selection acts upon, can be genotypic, phenotypic, and allelic

Three Requirements for natural selection

variation in the trait, fitness consequences of the trait, a mode of inheritance

Fixed trait

the only variation of a trait in a population

Heritability

a measure of the proportion of variance in a trait that is due to genetic influence, rather than environmental

Parent-Offspring Regression

testing for behavioral variation by observing if there is a high correlation between the parents and the offsprings despite differences in experience and environment (cliff swallows)

Cross-Fostering Experiment

Taking two young animals and switching where they grow up, allows to obersve impacts of rearing environment (Cliff swallows)

Selection Truncation Experiment

if a trait responds to selection then it is heritable, so test how much the behavior changes over a few rounds of artificial selection then quantify the heritability of the trait (crow approaching experiment)

Adaptation

a trait that results in its bearer having the highest fitness in a specific environment (Note: a trait may be an adaptation in one environment
and maladaptive in another) (Guppies Experiment)

Definition of Behavior

externally visible activity of an animal, in which a coordinated pattern of sensory,
motor and associated neural activity responds to changing internal and external conditions

Mechanism

What in the animal’s brain/physiology/genes causes it to behave the way it does?

Development

How does development affect behavior and how does behavior develop over an animal’s lifetime?

Evolutionary function

Does the behavior affect survival and/or reproduction?

Evolutionary history

Does the animal’s phylogenetic placement influence the behavior?

Major Transitions in Evolution Framework

cooperation between smaller units to become larger units

Characteristics of Eusociality

1) Reproductive division of labor 2) Overlapping generations 3) Cooperative care of young

Kin selection

Helping relatives allows an individual to pass some of its own genes to the next generation (gene’s eye view)

Phylogenetic tree

a way to visualize common ancestry

Homology

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

homoplasy

a trait that is shared between two or more species but is not a result of common ancestry

Principle of parsimony

the assumption that the simplest explanation is most likely to be the correct one

Responses from hormone signaling

changes in physiolgy and behavior (can be longterm)

Where are hormones located

internally in the tissues of the body

Hormone

chemical messenger that travels from endocrine cells to target cells

endocrine cells

specialized cell type with glandular structures to synthesize and secrete hormones

endocrine system

system of glands in an organism that secrete hormone into the blood or surrounding tissue

glandular tissue

specialized cells in the body

neurosecretory cells

specialized endocrine cells in the brain

peptide hormone

hormone molecule made out of protein molecules, coded for by DNA, fast acting (bind to receptors on cell membrane)

steriod hormone

hormone molecule derived from lipid substrate, cannot be stored, slower acting (bind to intracellular receptors)

Testosterone

Male sex hormone that when exposed to during early development results in more aggressive traits (Gerbil experiment)

Juvenile hormone

hormone that regulates development in insects, keeps then im larval stages, produced in corpora allata, high levels increase foraging behavior in bees

Central nervous system

comprised of the brain and spinal cord

Peripheral nervous system

motor neurons connect CNS to effector cells, sensory neurons relay external information to CNS (bundles of neuronal axons are called nerves)

Brain

a concentration of neurons at the front of an animal (all vertebrate brains have homologus regions)

Invertabrate nervous system

different from vertebrates but have homologus genes and chemicals

Neuron

basic unit of nervous system that receives electrical impulses

Glia

cells that support nerve structure and function

neurotransmitters

chemicals that are stored in the terminal of the nerve cell that are released into the synapse, chemical will bind to receptors in other nerves or effector cells

Effector cell

target cell

Anatomy of nervous system can impact learning

animals with larger spatial memory regions (hippocampi) were able to navigate better than individuals who did not (Meadow vs Prarie vole experiment)

Neural plasticity

the ability of brains and neural pathways to change in response to experience

Unihemispheric brain activity

organism is able to only use one half of its brain at a time (duck sleeping)

Neural plasticity in invertebrates

larger mushroom bodies in bees from more experiance foraging

Polygenetic traits

trait many many genes underlying them, some genes with large and some with small effects

What forces influence behavior

heredity and the environment

Expression

the extent of how much protein is being produced by a particular gene (activity of a gene)

Heritable genetic effect

different DNA sequences produce different proteins (fruit fly larvae)

Gene expression effect

the same gene can be expressed in different ways to get different behaviors (honey bee foraging)

Example of expression effect: hormone receptors

male voles with more vasopressin receptors tend to have monogamous behaviors (regulatory region controls expression)