1.1 Interaction of heredity and environment

Nature-nuture issue

The longstanding controversy over the relative contributions that genes & experience make to the development of psychological traits & behaviors. Today's science views traits & behaviors as arising from the interaction of nature & nature

Nature

Everything before conception, genes

Nurture

Everything after conception, environment

Natural selection

The principle that the inherited traits enabling an organism to survive and reproduce in a particular environment will (in competition with other trait variations) most likely be passed on to succeeding generations

Principle of natural selection

From among chance variations, nature selects those traits that best enable an organism to survive and reproduce in a specific environment

Evolutionary psychology

The study of the evolution of behavior and the mind, using principles of natural selection; how are we humans alike because of our shared biology and evolutionary history

Evolutionary psychologists

Seek to understand how our traits and behavior tendencies are shaped by natural selection

Behavior genetics/geneticists

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

Belyaev and trut

Fox domestication

Mutations

Random errors in gene replication that become nature's preliminary tests of alternative possibilities

Genome

Our common complete set of genetic instructions for making an organism

Environment

Every nongenetic influence, from parental nutrition to our experiences of the people and things around us

Heredity

The genetic transfer of characteristics from parents to offspring

Genes

Small segments of the giant DNA molecules, 46 chromosomes

Polygenic

A trait or characteristic is controlled by the combined action of two or more genes

Identical (monozygotic) twins

Develop from a single fertilized egg that splits; genetically identical

Fraternal (dizygotic) twins

Develop from two separate fertilized eggs; genetically no more similar than ordinary siblings

Genetic relatives

Biological parents and siblings

Environmental relatives

Adoptive parents and siblings

Interact

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

Epigenetics

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

Epigenetic marks

Chemical tags attached to DNA or its packaging proteins that turn genes on or off without changing the underlying genetic code (often methyl molecules)

Heritability range

1 is genetics and 0 is environment

Eugenics

Scientifically inaccurate theory and practice of trying to improve the human race through selective breeding

7 psychological perspectives

Psychodynamic, behavioral, cognitive, biological, humanistic, evolutionary, & sociocultural

Psychodynamic

Focuses on the unconscious mind, early childhood experiences, and unresolved inner conflicts

Behavioral

Concentrates on observable behaviors learned through environmental conditioning, rewards, and punishments

Cognitive

Focused on internal mental processes, this view compares the mind to a computer to study memory, problem-solving, perception, and decision-making

Biological

Examines the physical and biological bases of behavior, including genetics, brain structures, hormones, and neurotransmitters

Humanistic

Free-will, personal growth, motivation, and drive toward self acutalization

Evolutionary

Applies principles of natural selection and survival advantages to explain why certain psychological traits and behaviors evolved over time

Sociocultural

Examines how social norms, cultural values, ethnicity, and economic factors shape human thought and behavior