Evolution can select traits that are good for individuals, but bad for the species as a whole ANTAGONISM is built into the nature of sexual reproduction itself. Members of each sex try to maximise their own reproductive fitness, which is a combination of the quality and the quantity of offspring they are able to raise to the point where those offspring can themselves reproduce. If conflict between males and females is part and parcel of reproduction, some still have it much tougher than others. Spare a thought, in particular, for the females of the cowpea seed beetle. 

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