Here the investigator proposes to test, experimentally, three basic hypotheses on parental role division that were derived from correlational studies on humans. First, parental role division is based on the relative abilities and needs of each parent. Thus, the PI predicts that a large part of parental behavior is not based on inherent gender differences nor does a parent always attempt to off-load its responsibility onto the mate (as assumed in most studies on animals). However, he does anticipate that parental role conflicts will develop when parental differences are reduced. This conflict is manifested when both parents attempt to perform the same activity. Second, it is hypothesized that the resolution of this conflict is based on gender differences, and there is preliminary evidence that females dominate near the offspring while males may dominate away from the offspring. Third, it is hypothesized that gender differences also exist in the stimulus each parent uses in changing, or switching, parental roles. Preliminary evidence suggests that males begin offspring care when the female is absent while females begin irrespective of whether or not the male is present. Similarly, the female is predicted to increase her activities away from the offspring when the male is absent. The studies use the monogamous convict cichlid fish, Cichiasoma nigrofasciatum, as the animal model because, unlike mammals and birds, it is easy to manipulate parental abilities.