How Species Diversify

Science 2 November 2012: Vol. 338 no. 6107 pp. 619-621 DOI:10.1126/science.1224818

Perspective

How Cichlids Diversify

M. Emília Santos, Walter Salzburger | 0 Comments [Note, I tried several times to comment on Nov. 2, 2012, but comments do not seem to be open — despite my AAAS membership.]

Article excerpt: “The heterogeneous light conditions in this lake led to diversifying selection on opsin genes as a function of water depth. The divergence in opsins, in turn, affects sexual selection, because differences in color perception influence the female preference for male coloration (17). Here, the interplay between natural and sexual selection resulted in speciation in the absence of geographic barriers through selection on a sensory system (“sensory drive”).”

My comment: There is no animal model of female preference for male coloration that is not primarily dependent on sex differences in species-specific pheromones. Pheromones, not coloration, are responsible for epigenetic effects on intracellular signaling and stochastic gene expression in hormone-secreting nerve cells of tissue in vertebrate brains.

In mammals, these hormone-secreting nerve cells are the gonadotropin releasing hormone (GnRH) nerve cells that control the hypothalamic-pituitary-gonadal (HPG) axis and hypothalamic-pituitary adrenal (HPA) axis.

GnRH control of the HPG and HPA axis controls the adaptive evolution of behavior that links nutrient chemical-dependent individual survival to speciation via the metabolism of the nutrient chemicals to pheromones, which control reproduction. The reciprocal relationships are clear: 1) nutrient chemicals -> food acquisition 2) pheromones -> mate acquisition 3) adaptive evolution -> speciation via behaviors required for appropriate food choice and best mate choice in all animal species.

Cichlid species diversify via selection for food and pheromones like every other species on this planet. Attributing their diversity to selection for color (or a “sensory drive” associated with visual input) ignores the obvious fact that “Olfaction and odor receptors provide a clear evolutionary trail that can be followed from unicellular organisms to insects to humans.

The molecular mechanisms are conserved across species and they result in species radiation (i.e., diversity).  Thus, the perspective on evolution offered in this article is the wrong perspective. It is olfactory/pheromonal input that is responsible for the sensory drive and species diversity of Cichlids and the diversity of all species.

About James V. Kohl 1307 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