Sexual attraction existed in different cultures is controversial. Pheromones have been determined to play a role in sexual attraction between people. They influence gonadal hormone secretion, for example, follicle maturation in the ovaries in females and testosterone and sperm production in males. Research conducted by Donald G. Dutton and Arthur P. Aron in the 1970s aimed to find the relation between sexual attraction and high anxiety conditions. In doing so, 85 male participants were contacted by an attractive female interviewer at either a fear-arousing suspension bridge or a normal bridge. Conclusively, it was shown that the male participants who were asked to
Melanocyte-stimulating hormone when the animal is in a dark location. This causes pigment to be dispersed in pigment cells in the toad's skin, making it become darker, and harder for predators to spot. The pigment cells are called melanophores and therefore, in amphibians, the hormone is often called melanophore-stimulating hormone. An increase in MSH will cause darker skin in humans too. MSH increases in humans during pregnancy. This, along with increased estrogens, causes increased pigmentation in pregnant women. Cushing's disease due to excess adrenocorticotropic hormone (ACTH) may also result in hyperpigmentation, such as acanthosis nigricans in the axilla. Most people with primary