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The basic idea of evolutionary psychology is that psychological characteristics, like biological characteristics, may be passed on from one generation to another through hereditary material. Present-day psychological traits may be analyzed in terms of their evolutionary advantage for our ancestors. For example, males today tend to desire many mates while females desire one. According to evolutionary psychologists, this continues on to this day because it was an evolutionary advantage for males of the past to attempt to spread their genetic material as widely as possible because it increased their likelihood of passing on their own traits for future generations.