Counterargument: Genetic influences on behavior

In contrast to Zimbardo's situational determinism, Lykken (2000) argued that twin studies suggest genetic traits account for significant behavioral differences, with heritability estimates varying by trait (Plomin et al., 2016). Research on identical twins raised together shows that individual choices and experiences shape distinct personalities (Sinha, 2004). Furthermore, epigenetic studies demonstrate that environmental factors can modify gene expression, supporting a dynamic interaction between genetics and context (Meaney, 2010). Thus, Zimbardo's nature-versus-nurture framework oversimplifies the interplay of individual agency, genetics, and environment.