Rushton and Jensen are well-known for research on racial differences in intelligence. Jensen hypothesized a genetic basis for Black-White IQ differences in his 1969 Harvard Educational Review article. His later books Bias in Mental Tests (1980) and The g Factor (1998), as well as Rushton's (1995) Race, Evolution, and Behavior, show that tests are not biased against English speaking minorities and that Black-White-East Asian differences in brain size and IQ belong in an evolutionary framework.