“My opinion is that you will find differences wherever they were reinforced, because we love categories,. . .we need to have categories. And so once we’ve decided, once we’ve labeled ‘this is a girl,’ ‘this is a boy,’ then we have so many culturally strong biases that we maybe produce differences in abilities. So for example, in physical abilities, if we push boys to be more active and to deal with danger, then of course later in life when they’re children, they will look different. But that does not mean the differences were in the biology,” says Gliga.