Food odors and pheromones in flies (but not in flycatchers?)

Uncovering the genomic signatures of species differences in flycatchers. Speciation genetics (2013)  B Hansson.

Bill S. Hansson co-authored Attraction of Drosophila melanogaster males to food-related and fly odours

Abstract excerpt: “We showed that upwind flights are initiated by food odours. At shorter distances, males are attracted by volatiles produced by conspecifics. However, only odours produced by copulating flies attract males. This suggests either a synergistic effect of both male and female odours or changes in pheromone release during mating, that indicate the presence of sexually receptive females. Our findings demonstrate the essential role of food odours and pheromones for mate location in D. melanogaster.”

My comment: Is the same author/co-author suggesting that species differences in flies (D. melanogaster) might arise via different molecular mechanisms in flycatchers? If so, perhaps there is something to be said for mutations theory after all. But, I doubt it!

I’m more inclined to believe that the molecular mechanisms of speciation genetics are the same in species from microbes to man (as in my model).  Apparently, we can still rule out random mutations theory, however. For example, Hansson (2013) states:  “The divergence islands were non-randomly distributed across the genome and highly overrepresented towards chromosome ends.”

That suggests adaptive evolution occurs in flies and in flycatchers via the same non-random molecular mechanisms involving nutrient (e.g., food odors) and social odors (e.g., pheromones). But, until someone like Hansson clarifies how adaptive evolution occurs in some invertebrates but not vertebrates, most people may need to determine for themselves whether speciation is caused by food odors and pheromones (as in flies) or via unknown molecular mechanisms (as in flycatchers).

See also: Divergence of odorant signals within and between the two European subspecies of the house mouse. Behavioral Ecology (2008). “Our earlier studies documented mate preference and signal divergence between the 2 subspecies. Hence, we consider the role of the urinary odors as mating signals. We discuss how signal divergence between the 2 subspecies may relate to reproductive character displacement.”

And see: On the scent of speciation: the chemosensory system and its role in premating isolation.  Heredity (2009). “Although most studies of chemosensory speciation concern sexual isolation mediated by pheromone divergence, especially in Drosophila and moth species, other chemically based behaviours (habitat choice, pollinator attraction) can also play an important role in speciation and are likely to do so in a wide range of invertebrate and vertebrate species.”

My comment: If species divergence is not nutrient-dependent and pheromone-controlled in Drosophilia and moth species and in all invertebrates and in all vertebrates, like mice and flycatchers, what drives and controls species divergence? Is there a model for that?

About James V. Kohl 1308 Articles
James Vaughn Kohl was the first to accurately conceptualize human pheromones, and began presenting his findings to the scientific community in 1992. He continues to present to, and publish for, diverse scientific and lay audiences, while constantly monitoring the scientific presses for new information that is relevant to the development of his initial and ongoing conceptualization of human pheromones. Recently, Kohl integrated scientific evidence that pinpoints the evolved neurophysiological mechanism that links olfactory/pheromonal input to genes in hormone-secreting cells of tissue in a specific area of the brain that is primarily involved in the sensory integration of olfactory and visual input, and in the development of human sexual preferences. His award-winning 2007 article/book chapter on multisensory integration: The Mind’s Eyes: Human pheromones, neuroscience, and male sexual preferences followed an award winning 2001 publication: Human pheromones: integrating neuroendocrinology and ethology, which was coauthored by disinguished researchers from Vienna. Rarely do researchers win awards in multiple disciplines, but Kohl’s 2001 award was for neuroscience, and his 2007 “Reiss Theory” award was for social science. Kohl has worked as a medical laboratory scientist since 1974, and he has devoted more than twenty-five years to researching the relationship between the sense of smell and the development of human sexual preferences. Unlike many researchers who work with non-human subjects, medical laboratory scientists use the latest technology from many scientific disciplines to perform a variety of specialized diagnostic medical testing on people. James V. Kohl is certified with: * American Society for Clinical Pathology * American Medical Technologists James V. Kohl is a member of: * Society for Neuroscience * Society for Behavioral Neuroendocrinology * Association for Chemoreception Sciences * Society for the Scientific Study of Sexuality * International Society for Human Ethology * American Society for Clinical Laboratory Science * Mensa, the international high IQ society