On group differences in the heritability of intelligence: A reply to Giangrande and Turkheimer (2022)

Abstract

Here we reply to Giangrande and Turkheimer's (2022; G&T) recent critique of a meta-analysis we published in Intelligence regarding the Scarr-Rowe Hypothesis and the apparent lack of putative race/ethnic group differences in the heritability of intelligence (Pesta et al., 2020). Our rebuttal is divided into three sections that address ubiquitous misstatements in their critique: Section 1 focuses on conceptual and theoretical points. Section 2 addresses methodological, statistical, and interpretative points. Section 3 provides new analyses suggested by G&T that support our original interpretations. We note that G&T published their critique in Perspectives on Psychological Science (PoPS), which did not invite us to respond before their paper was published and our subsequent submission of a rebuttal was not accepted. Our unsuccessful appeal of these events based on possible ethics violations is detailed here (Appendix E). We recognize that this is a controversial area of research with legitimate disagreements and hope our responses maintain a degree of rigor and professionalism that others can emulate.