nature vs. nurture

When you have a small child, many conversations begin like this:
Another parent – often the expensively-educated New York Times-reading mother of at least one boy –will say, with the air of someone who is imparting a profoundly original thought, "You know, I always thought gender was socially constructed, but gosh, it’s just amazing how different boys and girls really are." Her inevitable conclusion? It’s all in their intractable little natures.