Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 exam•Written by the Fiveable Content Team • Last updated September 2025
Definition
Behavioral genetics is the study of how genes and environmental factors influence behavior. It examines the role of nature (genes) and nurture (environment) in shaping an individual's traits and behaviors.
Heritability refers to the extent to which differences in a trait between individuals can be attributed to genetic factors. For example, if intelligence has a high heritability, it means that genetic factors play a significant role in determining intelligence differences among people.
Gene-environment interaction: Gene-environment interaction occurs when genetic factors interact with environmental influences to produce certain outcomes or behaviors. An example would be how some people may have a genetic predisposition for developing alcoholism, but only if they are exposed to certain environmental triggers such as social pressure or availability of alcohol.
Epigenetics explores how changes in gene expression occur without changes to DNA sequence itself. It looks at how environmental factors can influence gene activity by "turning on" or "turning off" certain genes. An analogy here would be thinking of your genes as light switches that can be dimmed or brightened by different environmental influences.