It is actually well documented that males, independent of environmental influences, prefer "masculine" toys, such as trucks, while girls prefer dolls. While it's nice to think about nurture instead of nature, there are innate traits of each gender. Don't make the huge mistake in thinking that lead to David Reimer's suicide: http://en.wikipedia.org/wiki/David_Reimer

Here is an article citing several studies: http://www.psychologytoday.com/blog/homo-consumericus/201212...