The paper is excellent, though it doesn't support tola8's conclusion. Section 5.2. summarizes nicely.

The biology and psychology literature suggest that competitiveness results both from nurture and nature (see Niederle & Vesterlund 2007 for a discussion)

Economic research to date is consistent with nature, nurture, and the interaction between the two influencing an individual’s attitude toward competition. Although it is unclear, and likely to remain unclear, how much of this drive to compete can be attributed to nurture, there appears to be room for manipulating the preferences for competitions. Indeed, gender stereotypes held in a society have been shown to affect the performance of females on a stereotypical-male task such as math (Niederle & Vesterlund 2010, Pope & Sydnor 2010). If stereotypes can be changed, then it may be possible to encourage more women to compete on stereotypical-male tasks.