A series of studies conducted by the University of Zurich have found that women tend to be a lot more kind and generous than men.
The study looked at how each gender responded to 'prosocial' (or kind) behaviour. The results showed that women showed a much higher feeling of satisfaction after doing something kind than men did, in return they were incentivised to do something kind more often.
The researchers noted that "the reward and learning systems in our brains work in close cooperation. Empirical studies show that girls are rewarded with praise for “prosocial” behaviour, implying that their reward systems learn to expect a reward for helping behaviour instead of selfish behaviour."
"With this in mind, the gender differences that we observed in our studies could best be attributed to the different cultural expectations placed on men and women."