http://www.newscientist.com/article/...fair-play.html

Comparing the hormone data with the results of the money game showed a correlation between high testosterone levels and an increased likelihood of refusing the low, "unfair" offer of $5.

Men who rejected the deal had an average testosterone count of 380 picomoles per litre of saliva, whereas those who accepted it had an average of almost 40% of that figure.
which basically means, selfish maximisers, the - according to economists, the optimum attitude - to always take the best offer, does not tally with real behaviour men - except that lower testosterone males will behave as selfish maximisers. willing serfs.

in other studies it is revealed that in general humanity rejects self-maximiser attitude. so fair play and socialism is innate - opposition is deviant.