Glossary
Adaptive Behaviors
Behaviors that have evolved because they increased an organism's chances of survival and reproductive success in its environment.
Example:
The human tendency to form social groups is considered an adaptive behavior because it provided safety and resources for early humans.
Adoption Studies
A research method that compares adopted children to both their biological and adoptive families to differentiate between genetic and environmental influences on traits.
Example:
If an adopted child's personality traits are more similar to their biological parents than their adoptive parents, an adoption study would suggest a genetic influence.
Behavior Genetics
The scientific study of the relative power and limits of genetic and environmental influences on behavior. It investigates how heredity and environment interact to shape individual differences.
Example:
Behavior genetics research often uses twin and adoption studies to disentangle the contributions of nature and nurture to personality traits like extroversion.
Biological Psychology
The scientific study of the links between biological processes (like genetics, neural activity, and hormones) and psychological processes (like thoughts, emotions, and behaviors).
Example:
A biological psychologist might investigate how specific brain regions are activated when someone experiences intense fear.
Biopsychosocial Approach
An integrated perspective that considers the combined influence of biological, psychological, and social-cultural factors on behavior and mental processes.
Example:
Understanding why someone develops an eating disorder requires a biopsychosocial approach, considering genetic predispositions, body image perceptions, and societal pressures.
Chromosomes
Thread-like structures found within the nucleus of cells, composed of DNA and proteins, that carry genetic information in the form of genes. Humans typically have 23 pairs.
Example:
Each human cell contains 46 chromosomes, which are essentially the organized packages of our genetic code, determining our inherited traits.
DNA
Deoxyribonucleic acid, a complex molecule containing the genetic instructions used in the development and functioning of all known living organisms. It forms the basic building blocks of chromosomes.
Example:
The unique sequence of your DNA determines everything from your eye color to your predisposition for certain personality traits.
Environment
Every non-genetic influence, ranging from prenatal nutrition and exposure to toxins to social interactions, cultural norms, and educational experiences.
Example:
A child's environment, including their family's parenting style and access to quality education, significantly impacts their cognitive and social development.
Epigenetics
The study of how environmental factors can influence gene expression without altering the underlying DNA sequence. These changes can turn genes on or off, affecting an organism's traits.
Example:
A person's diet and stress levels can lead to epigenetic changes, influencing how their genes are expressed and potentially impacting their health or mood.
Eugenics
A discredited and unethical movement based on the idea that selective breeding can 'improve' the human race by promoting desirable traits and discouraging undesirable ones.
Example:
Historically, the eugenics movement led to forced sterilizations and discriminatory policies against marginalized groups.
Evolutionary Psychology
A field of psychology that applies the principles of natural selection to understand the origins and functions of human behaviors and mental processes.
Example:
Evolutionary psychology might explore why humans tend to be attracted to certain physical features, linking it to ancestral reproductive advantages.
Evolutionary Psychology
A field that studies how natural selection has shaped human behavior and mental processes over generations. It seeks to explain universal human traits and behaviors from an evolutionary perspective.
Example:
An evolutionary psychologist might explain why humans have a universal preference for sweet and fatty foods as a survival mechanism developed when food was scarce.
Family Studies
A research method that examines how traits are shared among genetically related individuals within a family to determine if a trait has a genetic basis.
Example:
Observing that a particular artistic talent appears consistently across several generations in a family might be explored through family studies.
Fraternal (Dizygotic) Twins
Twins who develop from two separate fertilized eggs at the same time, making them genetically no more similar than regular siblings.
Example:
Comparing the similarities between fraternal twins and identical twins helps researchers estimate the heritability of various traits, such as susceptibility to certain phobias.
Genes
Segments of DNA located on chromosomes that serve as the basic units of heredity, coding for specific traits or proteins. They are the blueprints for an organism's characteristics.
Example:
A specific gene might influence whether someone has a natural talent for music or a tendency towards shyness.
Genome
The complete set of genetic material (DNA) present in an organism or cell. It contains all the instructions needed to build and maintain that organism.
Example:
Scientists are working to map the human genome to understand the full genetic makeup that defines our species.
Heritability
The proportion of variation among individuals in a group that can be attributed to genetic factors. It is a population-level statistic, not an individual one.
Example:
If the heritability of a specific personality trait is found to be high, it means that genetic differences account for a large portion of the variation in that trait across a group of people.
Identical (Monozygotic) Twins
Twins who develop from a single fertilized egg that splits into two, resulting in two individuals with nearly identical genetic material.
Example:
Studying identical twins raised in different homes can provide valuable insights into the impact of environment on traits that are largely genetic, like intelligence.
Interaction
The interplay between genetic predispositions and environmental influences, where the effect of one factor depends on the presence or level of another.
Example:
A genetic predisposition for musical talent might only flourish if an individual is exposed to music lessons and encouragement, demonstrating the interaction between nature and nurture.
Molecular Genetics
A subfield of biology that studies the structure and function of genes at a molecular level. It focuses on identifying specific genes that influence behavior.
Example:
Researchers in molecular genetics might investigate which specific genes are linked to a higher risk of developing a particular mental health condition.
Mutations
Random errors in gene replication that can lead to changes in the DNA sequence, potentially introducing new traits or variations.
Example:
A spontaneous mutation in a gene could lead to a new physical characteristic, like a unique hair color, or even a beneficial adaptation in a species.
Natural Selection
A core principle of evolutionary psychology where traits and behaviors that enhance an organism's survival and reproduction are more likely to be passed down to subsequent generations.
Example:
The development of camouflage in certain animals is a result of natural selection, as it helps them avoid predators and survive.
Natural Selection
The principle that traits contributing to survival and reproduction are more likely to be passed on to succeeding generations. Organisms with advantageous traits are more likely to survive and reproduce.
Example:
The development of a strong fight-or-flight response in humans is a result of natural selection, as those who reacted quickly to threats were more likely to survive and pass on their genes.
Nature
Refers to the influence of an individual's inherited genetic makeup on their development, including physical traits, behavioral tendencies, and mental abilities.
Example:
A person's natural hair color and eye color are examples of traits determined by their nature.
Nurture
Encompasses all the environmental factors and experiences that shape an individual's development, such as family interactions, education, culture, and life events.
Example:
The language a child learns to speak and their cultural traditions are heavily influenced by nurture.
Twin Studies
A research method used to investigate the relative contributions of genetics and environment by comparing the similarities between identical twins and fraternal twins.
Example:
If identical twins are more likely to share a specific phobia than fraternal twins, a twin study would suggest a genetic component to that phobia.