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Modal Pheromones

Thiessen et al. (1968) report that dominant gerbils ‘ventral rub’ their environment more frequently than subordinates. Ralls (1971) quotes the unpublished work of Johnston on golden hamsters in which dominant males apply their male pheromones organs to the arena many times more often than do subordinates. She quotes similar results of work with rabbits, sugar gliders, marmosets, Maxwell's duikers and pangolins. The need to express dominance is thus as strong in small mammals as it is in large and there can be no other explanation of these results. The role of Human Pheromone Odors 15.4.3. Individual range and territory maintenance The question of territorial and individual range marking amonst pheromone users and related issues is also the subject of a separate communication in this volume (Mykytowycz ch. 17) and will not be dealt with here. The main questions for further research must involve a critical analysis of exactly what messages are conveyed by the odor used in marking and the identification of the active ingredients responsible for each message. 15.4.4. Family and clan cohesion Cohesion of the social group of pheromone users, whether it be family or clan, appears to depend upon olfactory communication. Indeed the mother rat has been shown to recognize the odor of her young and selectively choose her own from a large group (Beach and Jaynes 1956). 

The existence of a ‘maternal pheromone’ has been identified in lactating mice and rats (Cowley and Wise 1970; Leon and Moltz 1971, respectively). This substance emitted from the female has an attractant effect on pre-weanling juveniles. Given the choice between an air stream tainted by a lactating rat and untainted air, a strong selection is made for the tainted air. Rat pups moved as readily towards any lactating female as towards their mother, thus demonstrating that the cue is not litter specific. In an extension of this pheromone, Leon and Moltz (1972) showed that the substance is first emitted on about the 14th day of lactation at which time the pups are starting to leave the nest. By testing whether young of various ages from one to 41 days choose to go towards their own mother or a nulliparous female, it appears that by 14 days the young begin to approach their own mother preferentially.  Learn more at

The preference is lost by 41 days. By testing young of 16 days with lactating females at different stages of lactation, it appears that they start emitting the substance at about the time the young are able to perceive it and cease to produce it at the time the young are no longer able to perceive it. Since it is known that a sharp decline in retrieving behavior by the mother occurs at about 14 days, it is thought that the pheromonal bond serves to attract the young to the mother for the remaining two weeks of lactation. The site of production of the maternal pheromone is not known, but the mammary glands cannot be overlooked as a possible site. (It is interesting to note in passing that components in human and pig milk occur in the same proportions throughout lactation, but in the echidna, platypus and kangaroo the ratio of high palmitic acid/C18 unsaturated acids in early milk changes to a low one in late milk. In these species at least, the mammary gland is constantly able to change the composition of its secretory output (Griffiths et al. 1972).)