Chapter 4 - Behavioral Genetics

Flashcards covering the foundational concepts of behavioral genetics, including heritability, genetic variation, gene expression, and animal personalities based on Lecture 4.

Phenotype (P)

The observed traits of an individual, which result from the interaction between the genotype and the environment.

Genotype (G)

The complete set of all the alleles of an individual.

Behavioral Genetics

The study of how genes and the environment lead to individual phenotypic differences.

Heritability ($h^2$)

The proportion of phenotypic variation in a trait that is due to genetic influences.

Broad-sense heritability

A measurement of heritability that includes all genetic effects on the phenotype.

Additive effects (A)

The average effect of individual alleles on the phenotype.

Dominance effects (D)

The interactions between alleles at a single locus.

Epistasis (I)

The interactions between genes located at different loci.

Genetic variation formula

The representation of genetic variation as the sum of additive, dominance, and epistatic effects: $V_G = V_A + V_D + V_I$.

Narrow-sense heritability

The proportion of phenotypic variance that is due only to additive genetic values.

Parent/Offspring Regressions

A method used to assess narrow-sense heritability; a greater slope indicates that offspring more closely resemble their parents due to additive genetic variance.

Innate behaviors

Behaviors that are performed the same way each time, fully expressed the first time, and present even in individuals raised in isolation.

Reflexes

Involuntary movements made in response to a specific stimulus.

Fixed action pattern

A behavior displaying almost no variation that, once started, cannot be stopped until it is completed.

Wild-type

The typical form of an organism or gene as it occurs most commonly in nature.

Major gene

An individual gene that is responsible for a large amount of phenotypic variation.

Minor gene

An individual gene that contributes only small amounts of variation to a phenotype.

Pleiotropy

A condition where a single gene affects more than one phenotypic trait, such as the "yellow" gene in fruit flies affecting both body color and courtship.

Monogyne

A social organization in fire ant colonies where there is a single reproductive queen.

Polygyne

A social organization in fire ant colonies characterized by multiple reproductive queens.

Supergene

A set of linked genes that function together to affect many different traits.

Knockout technique

An experimental procedure used to disable or eliminate the expression of a specific gene to examine its influence on behavior.

Thigmotaxis

A preference for physical contact, often used as a measure of anxiety in mice during stress tests.

Quantitative trait loci (QTL)

Stretches of DNA that either contain or are closely linked to genes influencing a specific phenotypic trait.

QTL mapping

A statistical technique that combines genetic information with trait information to identify regions of the genome containing genes that influence a trait.

Candidate genes

Major genes that are suspected of contributing to a large amount of the phenotypic variation in a specific trait.

Gene expression

The process by which gene products are formed, which is dependent on environmental and sensory inputs.

Closed-ended learners

Individuals, such as some bird species, that must hear a tutor sing a specific song during a "sensitive period" shortly after hatching to learn it correctly.

Open-ended learners

Individuals that have the ability to acquire and add new song elements to their repertoire throughout their entire life.

Spectrogram (sonogram)

A visual representation used by researchers to characterize the acoustic structure of vocalizations.

Reaction norm

The range of behaviors or phenotypes expressed by a single genotype when exposed to different environments.

Phenotypic Plasticity

The capacity of a single genotype to produce different phenotypes in response to varying environmental conditions.

Gene-environment interaction (GEI)

A situation where the environment has a significantly greater effect on one genotype than on others.

Sneaker males

Subordinate males in certain fish species that are smaller and behave or look like females to achieve mating success without defending a territory.

Animal Personalities

Consistent individual differences in behavior within a population that persist over time or across different environmental contexts.