Pheromone dominance

Ayasse M., Maelovits T., Tengo J., Taghizadeh T. and Francke W. (1995). Are there pheromonal dominance signals in the bumblebee Bombus hypnorum L. (Hymenoptera, Apidae) Apidologie, 26,163-180. 

Pheromonal dominance and the selection of a socially parasitic honeybee worker lineage (Apis mellifera capensis Esch.)../. Evol. Biol., 20, 997-1007. 

Species of pine sawflies in the genera Neodiprion and Pi prion secrete a sex pheromone dominated by either the acetate or propionate esters of 3,7-dimethylpentadecan-2-ol (138). Reproductive isolation of these sawflies appears to be partly related to the utilization of one or the other of these diasteriomeric esters. 

As the search progresses, deposited pheromone dominates ants selectivity, reducing the randomness of the algorithm. Therefore, ACO is an exploitive algorithm that seeks solutions using information gathered previously, and performs its search in the vicinity of good solutions. However, since the ant s movements are stochastic. 

Gangrade B. and Dominic C. (1985). Evaluation of the involvement of the vomeronasal organ in the pheromonal influences on the estrous cycle of the laboratory mouse. Anim Reprod Sci 8, 181-185. 

Cairns, B. R., Ramer, S. W., and Komberg, R. D. (1992). Order of action of components in the yeast pheromone response pathway revealed with a dominant allele of the STEU kinase and the multiple phosphorylation of the STE7 kinase. Genes Dev. 6 1305-1318. 

The queen is usually reproductively dominant within the colony and uses chemical cues as both primer and releaser pheromones to suppress the production or fecundity of other sexuals, inhibit reproduction by worker castes, modulate reproductive behaviors (e.g., inhibit swarming and orient swarms), attract males, regulate worker tasks and worker ontogeny, and produce host repellents in slave-making species. Considering the importance of queen semiochemicals in social hymenoptera, few queen pheromones have been chemically identified. The queens of most social hymenopteran colonies are attractive to workers, allowing them to be properly tended as well as to facilitate the dissemination of other pheromone cues. However, the retinue pheromone has been chemically identified in very few species. In the 1980s, queen pheromone components were identified in the fire ant, Solenopsis invicta [91,92], and in the Pharaoh s ant, Monomoriumpharaonis [93]. 

Compared with the protein content of mental gland secretions of P. shermani males, the protein profile for D. ocoee showed a much more complex pattern of protein staining (Fig. 20.4). In D. ocoee, no single dominant protein occurred in this nonolfactory pheromone profile. 

One may wonder why lobsters appear to use urine as a dispersal solvent for chemical signals, whereas terrestrial arthropods such as the well-studied insects use direct release of gland products into the air. Perhaps the answer is that small animals in air (such as insects) are always in danger of desiccation. By contrast, marine lobsters and crabs are relatively large and may experience only minor water loss problems due to osmosis. Thus, it may not be difficult for a 500-g lobster to store 10 ml of urine and release it during a dominance battle at a rate of up to 1 ml/min (27). The advantage of urine-carried pheromones is that the dispersal mechanism already exists urine is injected into the gill current, which in turn injects into ocean currents. 

The list of pheromone controls on reproductive behavior can be extended female pheromones inhibit estrus in adult females and delay puberty in juvenile females, Lee-Boot effect male pheromones can block pregnancy, Bruce effect pheromones from dominant females can suppress reproduction in subordinate females and so on. Have a look at Wyatt s book for an abundance of examples. 

Pheromone propagation by wind depends on the release rate of the pheromone (or any other odor) and air movements (turbulent dispersion). In wind, the turbulent diffusivity overwhelms the diffusion properties of a volatile compound or mixture itself. Diffusion properties are now properties of wind structure and boundary surfaces, and preferably termed dispersion coefficients. Two models have dominated the discussion of insect pheromone propagation. These are the time-average model (Sutton, 1953) and the Gaussian plume model. 

Metabolites in urine or feces provide the energetically least expensive, and evolutionarily probably the original, chemical signals in vertebrates. Much of history of evolution has concerned the development by living things of responses to metabolites, sometimes their own and sometimes produced by others. Those organisms which developed satisfactory responses succeeded, and those which did not, failed. (Lucas, 1944). Interested parties, such as members of the opposite sex, can then spy and read pertinent information about sexual and dominance status, health and body condition, quality of diet, and more. For instance, female goldfish release sex pheromones in their urine that... 

Changing the diet of a fish may change the behavior of conspecifics it interacts with subsequently. For instance, if one of a pair of male brown bullhead, I. nebulosus (a catfish), is removed from the tank and fed beef liver instead of the usual trout chow and then returned to his partner in their original tank, the resident will behave differently than if the same male is reintroduced without a diet change. The former tank mate is now a chemical stranger. The behavior changes include loss of territory and more activity by the smaller, manipulated fish and more aggression and activity by the resident fish. These diet-dependent odors are not specialized pheromones, and yet they are probably important social chemical cues in the natural territorial and dominance behavior of bullhead catfish. Body odor is the more appropriate term (Bryant and Atema, 1987). 

In the second part of this chapter, we discuss communication by pheromones and pheromone-like chemicals in the context of competition, aggression, dominance, and territorial behavior. 

Chapter 6 discussed signaling pheromones that allow discrimination, recognition, and broadcasting dominance and territorial status. This chapter explores the role of pheromones and other odors in reproduction, alarm, trail following, and in connection with food. Some evolutionary considerations conclude the discussion of signaling pheromones. 

Male mouse urine applied directly to the external nares of the female produces pregnancy block (Dominic, 1964). In mice, the vomeronasal mediates this block (Bellringer etal., 1980). The pregnancy-block pheromone of the male may be a product of androgen metabolism, and not one of androgen-dependent... 

Many of the fragrances and tastes from plants are due to esters. The smells we perceive are generally due to a combination of esters, but often one ester fragrance will dominant. By mimicking these natural esters, the food industry has synthesized hundreds of different flavoring agents. Three of these are shown in Figure 15.14. Many pheromones are esters. Pheromones are chemical compounds used by animals for communication. Many medications are also esters. Aspirin is an ester of salicylic acid (see Chapter 13). 

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