behavior geneticists

While most behavior geneticists agree that a large component of intelligence is inherited, they would say that the contribution of environment is also significant.

Psychologists and behavior geneticists began using twin studies in the 1980s to study variation in social attitudes, and these studies suggested that both genes and environment played a role.

In his response, Jensen cites the Synderman and Rothman study as a "thorough presentation of expert opinion among behavior geneticists and psychometricians" on the subject of intelligence.

Thus rather than "nurture", behavior geneticists distinguish shared family factors (i.e., those shared by siblings, making them more similar) and nonshared factors (i.e., those that uniquely affect individuals, making siblings different).

Rather, it has become a widely accepted belief among behavior geneticists that the superiority of the bright rats was confined to Tryon's specific test; thus, it is not possible to claim that there is a difference in learning capacity between the two groups of rats.