Question

Which of the following is/are included under behavioural genetics studies in humans?

• A. Selective breeding studies
• B. Family studies
• C. Twin studies
• D. Adoption studies

Hint:

For human behavioural genetics, remember the trio: {family, twin, adoption}. Anything requiring experimental mating (selective breeding) is out for humans.

Answer 1

The Correct Option is B, C, D

Step 1: Concept. Behavioural genetics in {humans} infers genetic and environmental influences using naturally occurring relationships, not experimental breeding. The classic human designs are {family}, {twin}, and {adoption} studies.

Step 2: Evaluate options.
(A) Selective breeding studies — Not used in humans (unethical/implausible). \Rightarrow Not included.
(B) Family studies — Compare trait similarity among biological relatives across degrees of relatedness. \Rightarrow Included.
(C) Twin studies — Compare MZ vs DZ twins to partition heritability and shared environment. \Rightarrow Included.
(D) Adoption studies — Contrast resemblance to biological vs adoptive parents to separate genes from rearing environment. \Rightarrow Included.
Conclusion: Only (B), (C), and (D) are human behavioural genetics methods.