IN 1875, three decades before genes officially arrived on the scientific scene, : “Twins have a special claim on our attention… their history affords means of distinguishing between the effects of tendencies received at birth, and those that were imposed by the special circumstances of their after lives.” With today’s flood of information from genetics, and with results from many studies of monozygotic (identical) twins raised together and apart, the promise implicit in Galton’s observation should be close to fulfilment. Are we on the brink of knowing conclusively which of nature and nurture is dominant in making us what we are?…
