What is commonly considered a significant influence on IQ when comparing adopted children in high SES and their biological siblings?

Socioeconomic status (SES) is a significant influence on IQ, particularly when examining adopted children in high SES households compared to their biological siblings who may not have the same advantages. Children raised in high SES environments often have access to resources such as better educational opportunities, enrichment programs, and supportive family environments, all of which can enhance cognitive development.

In the case of adopted children, their IQ may be more influenced by the environment provided by their adoptive families than by their biological families, especially if the adoptive families have a high SES. This highlights the impact that socio-economic factors have on intellectual development. Although parental education and peer influence can also impact IQ, the overwhelming influence of a supportive and resource-rich environment associated with higher SES is pivotal in this context. Therefore, the role of socioeconomic status stands out as a primary factor in determining the cognitive abilities of adopted children.