“…In mammals, fatty acids can be produced and released from other common tissue of mammals such as sweat gland, vagina, tear gland and fur in addition to mammary gland and milk, which may communicate the presence of mother or of other members of the same species [12][13][14][15][16][17] . In some mammalian species, fatty acids are also present and released in urine and specialized scent glands with the identified pheromones in rats, golden hamsters, musk rats, etc [18][19][20] . However, few fatty acids were detected in the urine and preputial glands in mice, and if fatty acids function as appeasing pheromones in mice, they are supposed to arise from the above-mentioned organs common to mammals, explaining why fatty acids are common appeasing pheromones in all mammals 2,21,22 .…”