She and others found in study after study that boys on average really do prefer to play with trucks and cars, while girls on average prefer dolls. ‘The main toys are vehicles and dolls. Those are the most gendered type of toys,’ she says. A study that Hines and her colleagues carried out on infants in 2010, observing how long they looked at one toy rather than another, suggested that these preferences start to emerge before the age of two.
