Cardiovascular responses in adult male and female alloparents during exposure to a novel, unrelated pup, 1-3 days old. Similar to adult males, females showed a sustained increase in heart rate while caring for a pup, which was accompanied by a decrease in RSA. There were no sex differences in terms of either heart rate or RSA while caring for a pup. Different letters denote significant differences from baseline (p<0.05), such that heart rate increased (A,B) and RSA decreased (C,D) following presentation of a pup in both sexes.