Basten , U. , Hilger , K. & Fiebach , C. J. ( 2015 ) Where smart brains are different: a quantitative meta-analysis of functional and structural brain imaging studies on intelligence . Intelligence 51 , 10 – 27 .

Broca , P. ( 1873 ) Sur les cranes de la caverne de l’Homme Mort . Revued’Anthropologie 2 , 1 – 53 .

Deary , I. J. , Whalley , L. J. & Starr , J. M. ( 2009 ) A Lifetime of Intelligence . American Psychological Association , Washington, DC .

Gale , C. ( 2005 ) Commentary: height and intelligence . International Journal of Epidemiology 34 , 678 – 679 .

Galton , F. ( 1888 ) Head growth in students at the university of Cambridge . Nature 38 , 14 – 15 .

Lynn , R. ( 1990 ) The role of nutrition in secular increases of intelligence . Personality and Individual Differences 11 , 273 – 285 .

Lynn , R. ( 1994 ) Sex differences in intelligence and brain size: a paradox resolved . Personality and Individual Differences 17 , 257 – 271 .

Lynn , R. & Harland , E. P. ( 1998 ) A positive effect of iron supplementation on the IQs of iron deficient children . Personality and Individual Differences 24 , 883 – 887 .

Pietschnig , J. , Penke , L. , Wicherts , J. M. , Zeiler , M. & Voracek , M. ( 2015 ) Meta-analysis of associations between human brain volume and intelligence differences: how strong are they and what do they mean? Neuroscience & Biobehavioral Reviews 57 , 411 – 432 .

Porter , W. T. ( 1892 ) The physical basis of precocity and dullness . Transactions of Academy of Science of St. Louis 6 , 161 – 181 .

Raven , J. , Raven , J. C. & Court , J. H. ( 2000 ) Standard Progressive Matrices . Oxford Psychologists Press , Oxford .

Raven , J. H. ( 2008 ) Standard Progressive Matrices Plus . Pearson , London .

Ritchie , S. J. , Booth , T. , Valdés Hernández , M. D. C. , Corley , J. , Maniega , S. M. , Gow , A. J. & Deary , I. J. ( 2015 ) Beyond a bigger brain: multivariable structural brain imaging and intelligence . Intelligence 51 , 47 – 56 .

Rushton , J. P. ( 2000 ) Race, Evolution and Behavior . Charles Darwin Research Institute , Port Huron, MI .

Rushton , J. P. & Ankney , C. D. ( 2009 ) Whole brain circumference and general mental ability: a review . International Journal of Neuroscience 119 ( 5 ), 692 – 732 .

Vernon , P. A. , Wickett , J. C. , Bazana , P. G. & Stelmack , R. M. ( 2000 ) The neuropsychology and neurophysiology of human intelligence . In Sternberg, R. J. (ed.) Handbook of Intelligence . Cambridge University Press , Cambridge, UK .

Walker , S. P. , Grantham-McGregor , S. M. , Powell , C. A. & Chang , S. M. ( 2000 ) Effects of growth restriction in early childhood on growth, IQ, and cognition at age 11 to 12 years and the benefits of nutritional supplementation and psychosocial stimulation . Journal of Pediatrics 137 , 36 – 41 .