The linked study is a lot more interesting than this article:

http://www.gsb.stanford.edu/news/research/halevy_nice_2011.h...

Some choice excerpts:

"Our findings show that people want respectable and admired group members to lead them at times of peace, but when 'the going gets tough' they want a dominant, power-seeking individual to lead the group,"

"...sharing one's resources with both in-group members and outsiders had the most dire net outcomes on a person's status. The researchers discovered that universal generosity decreased perceptions of both prestige and dominance compared with those who shared resources only with members of their group."