Sex differences, environmental complexity, and mother-infant relations.
D000375:Aging; D000818:Animals; D000831:Animals, Newborn / Q000254:growth & development*; D001143:Arousal; D004644:Emotions; D004777:Environment; D005260:Female; D006234:Handling, Psychological; D000882:Haplorhini; D006801:Humans; D008297:Male; D008425:Maternal Behavior; D012737:Sex Factors; D012919:Social Behavior; D012931:Social Environment; D013045:Species Specificity