Posted on: 02 March, 2017
Author: Alexander P
Let us discuss the top pheromones. The term aphrodisiac is widely used to describe this phenomenon, but care should be exercised in its use because of anthropomorphism, the tendency of anecdotal obser... Let us discuss the top pheromones. The term aphrodisiac is widely used to describe this phenomenon, but care should be exercised in its use because of anthropomorphism, the tendency of anecdotal observations to be given more credence than they deserve, and the assumption that an aphrodisiac is always successful. Male aphrodisiacs are wide- spread and most well known from the Lepidoptera, but even in this group we know little about the initimate behavioral interactions, the role of these pheromones in the population biology of the insects, or their signicance in pheromone evolution. The brush-organs of the Sphingidae may now be at this stage of development. Many sphingid species have complex male abdominal brush-organs (Birch 1969; Grant and Eaton 1973), which are everted as part of a warning/defensive display when handled or disturbed. This may be the primitive function of male scent organs in general (Birch 1970c), but it is difficult to see how only one sex could develop such a defensive mechanism unless the defensive function arose secondarily (Grant and Eaton 1973) or coincidentally with a sexual function. There is virtually no evidence as to the real function of the brushes. A different line of development could have been by specializing from a more generalized male sex pheromone. For example, males of Achroia grisella (Fabr.), the lesser waxmoth, produce an attractant pheromone: the female, as far as is known, produces no sex pheromone. The male pheromone attracts females and, together with auditory stimuli, facilitates copulation (Dahm et al. 1971). This may have been the primitive role of male aphrodisiac pheromones with the attractant function being later taken over by the female according to http://thongchaimedical.org/benefits-of-using-human-pheromone/ All we can say at present is that the male pheromones and their organs of production have evolved by some means, that they have evolved independently many times, and also have been lost very many times. The selection pressures behind their evolution (and subsequent loss) may be one or many, probably the latter. However, where they exist. the male pheromones are used in courtship. Aggregation pheromones in the Scolytidae Insect aggregation pheromones cause ‘other members of the same species to aggregate in a particular area’ (Shorey 1973). With a few possible exceptions, they occur throughout the family Scolytidae (Coleoptera) (Borden and Stokkink 1971), in which large numbers of beetles of both sexes are characteristically attracted. Thus, the pheromones serve as population aggregation pheromones. ln the majority of scolytid species, the beetles construct galleries in living or recently felled trees beetles in the phloem tissue, and ambrosia (timber) beetles in the xylem tissue. ’l'hcse habits render scolytid beetles extremely important pests of forests and timber, particularly in North America (Davidson and Prentice 1967). It is well known that scolytids aggregate in great numbers in a mass attack on selected hosts. 'l'his mass attack (aggregation) is considered essential to overcome the resistance of u living host tree (Anderson 1948) or to utilize temporary habitats to their fullest extent (Atkins 1966a). The possibility that scolytids use odor to help them find their host was investigated as early as 1916 (Miller and Keen 1960). However, Anderson (1948) produced the first evidence for population aggregation pheromones. Source: Free Articles from ArticlesFactory.com Alexander P is a blogger who studies pheromones. He is from Los Angeles, CA.