Nature, Nurture, and Human Diversity

Behavior genetics

The study of the relative power and limits of genetic and environmental influences on behavior.

Heredity

The genetic transfer of characteristics from parents to offspring.

(Eg. Height and eye color influenced by parents)

Environment

Every non genetic influence, from prenatal nutrition to the people and things around us.

(Eg. Parenting styles and education)

Chromosome

Threadlike structures made of DNA molecules that contain the genes.

DNA

AKA Deoxyribonucleic acid.

A complex molecule containing the genetic information that makes up the chromosomes.

Genes

The biochemical units of heredity that make up the chromosomes; small segments of DNA capable of synthesizing proteins.

Genome

The complete instructions for making an organism ,consisting of all the genetic material in that organism's chromosomes.

Monozygotic twins

AKA Identical twins.

Individuals who developed from a single fertilized egg that split in two, creating two genetically identical organisms.

Dizygotic twins

AKA Fraternal twins.

Individuals who developed from separate fertilized eggs. They are genetically no closer than ordinary siblings, but shared a prenatal environment.

Temperament

A person's characteristic emotional reactivity and intensity.

(Eg. A shy baby is cautious and slow to warm up)

Heritability

The proportion of variation among individuals in a group that we can attribute to genes.

(Eg. Intelligence is partly heritable but schooling and culture play a role)

Interaction

The interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity).

(Eg. Genetic risk for depression may only show if triggered by stressful life events)

Molecular genetics

The subfield of biology that studies the molecular structure and function of genes.

Molecular behavior genetics

The study of how the structure and function of genes interact with our environment to influence behavior.

Epigenetics

The study of the molecular mechanisms by which environments can influence genetic expression (without a DNA change).

(Eg. Stress can activate genes associated with anxiety)

Culture

The enduring behaviors, ideas, attitudes, values, and traditions shared by a group of people and transmitted from one generation to the next.

(Eg. Greeting styles, parenting styles, dietary patterns, etc)

Norm

Understood rules for accepted and expected behavior. Norms prescribe "proper" behavior.

(Eg. Individuals from certain countries use only their right hand to eat)

Individualism

Giving priority to one's own goals over group goals and defining one's identity in terms of personal attributes rather than group identifications.

(Eg. Focussing on what do "I" want)

Collectivism

Giving priority to the goals of one's group (often one's extended family or work group) and defining one's identity accordingly.

(Eg. Focussing on what is best for the group/family)

Sex

In psychology, the biologically influenced characteristics by which people define male, female, and intersex.

Gender

In psychology, the behavioral characteristics that people associate with boy, girl, man, and woman.

Intersex

Possessing male and female biological sexual characteristics at birth.

Aggression

Any physical or verbal behavior intended to harm someone physically or emotionally.

(Eg. Physical violence such as hitting and pushing, verbal insults, and threats)

Relational aggression

An act of aggression (physical or verbal) intended to harm a person's relationship or social standing.

(Eg. Spreading rumors, social exclusion)

X chromosome

The sex chromosome found in males and females. Females typically have two X chromosomes; males typically have one. An X chromosome from each parent produces a female child.

Y chromosome

The sex chromosome typically found only in males. When paired with an X chromosome from the mother, it produces a male child

Testosterone

Secreted in greater amounts by males.

Stimulates the growth of the male sex organs during the fetal period, and the development of the male sex characteristics during puberty.

Estrogens

Sex hormones, such as estradiol, that contribute to female sex characteristics and are secreted in greater amounts by females than by males.

Puberty

The period of sexual maturation, during which a person usually becomes capable of reproducing.

Primary sex characteristics

The body structures (ovaries, testes, and external genitalia) that make sexual reproduction possible.

Secondary sex characteristics

Non-reproductive sexual traits, such as female breasts and hips, male voice quality, and body hair

Spermarche

A boy's first ejaculation, marking the start of puberty. Usually occurs around ages 12-14.

Menarche

A girl's first menstrual period, marking the start of puberty. Usually occurs within a year of age 12 ½.

Role

A set of expectations (norms) about a social position, defining how those in the position ought to behave.

(Eg. A parent is expected to nurture and guide children)

Gender role

A set of expected behaviors, attitudes, and traits for men and for women

Sexual aggression

Any physical or verbal behavior of a sexual nature that is unwanted or intended to harm someone physically or emotionally. Can be expressed as either sexual harassment or sexual assault.

Gender identity

Our sense of being male, female, neither, or some combination of male and female.

(Eg. binary, non- binary, etc)

Social learning theory

The theory that we learn social behavior by observing and imitating and by being rewarded or punished.

(Eg. Learning manners by observing older siblings or parents)

Gender typing

The acquisition of a traditional masculine or feminine role.

(Eg. Boys praised for being assertive and girls praised for being nurturing)

Androgyny

Displaying both traditionally masculine and traditionally feminine psychological characteristics.

(Eg. Comfortable expressing traits culturally labeled as "masculine" or "feminine"

Transgender

An umbrella term describing people whose gender identity or expression differs from that associated with their birth-assigned sex.