Archive for June, 2012
Bee research, human sweet perception, human pheromones, and metabolic disorders
“Bee research sheds light on human sweet perception, metabolic disorders.” June 29th, 2012.
The epigenetic effects of nutrient chemicals, like glucose, and their metabolism to pheromones sheds light on how what is known about the honeybee model organism explains metabolic disorders and other disorders in humans. For example, I use the honeybee model organism to detail the molecular biology of brain development in mammals.
Nutrient chemicals and pheromones are essential to brain development in the honeybee, in mammals, and in us. A diet-reponsive neurogenic niche links nutrient chemical intake to receptor-mediated brain development in mammals. Glucose regulates the hormone secreting nerve cells in this niche, which links it and other nutrient chemicals to levels of luteinizing hormone (LH) and brain development. The same neurogenic niche links mammalian pheromones to LH. Thus, the diet-responsive neurogenic niche appears to also respond to pheromones that regulate brain development.
There are many human pheromone deniers, evolutionary theorists, and psychotherapists who think our brain development and behavior is not substantially altered by pheromones. They need to start thinking clearly. Denying the role of human pheromones in the context of brain development and behavior is like denying the role of food odors in brain development and behavior in all species from insects to other mammals and to us.
The same pathway is involved, and I’ve detailed it in Human pheromones and food odors: epigenetic influences on the socioaffective nature of evolved behaviors.read more June 30, 2012 • 4:55 PM
Epigenetics: Not in Our Genes
Sunday Times, 17 June 2012
Book review of ” Identically Different” by Tim Spector
Excerpt: “This book concludes with a list of four genetic dogmas that have been overthrown: genes are not our essence; our genetic inheritance can be changed; environmental events can be “remembered” by cells; and what happens in your life can affect later generations. Or, to put it bluntly, almost everything you’ve been told about genetics is wrong.”
My Comments (added to the site, but reproduced below):
In an issue dedicated to THE NEUROSCIENCE AND EVOLUTIONARY ORIGINS OF SEXUAL LEARNING, I published: Human pheromones and food odors: epigenetic influences on the socioaffective nature of evolved behaviors.
The 10-page article details how the epigenetic influences of nutrient chemicals and pheromones cause adaptive evolution. This occurs via the required ecological, social, and neurogenic niche construction, which is what allows for our hormone-driven brain development and behavior (e.g., our socio-cognitive niche construction). The required pathway also is detailed and includes the required reciprocity at all levels: gene, cell, tissue, organ, organ system.
What’s painfully clear is the fact that endocrine disruptors and other toxins are responsible for disorders of brain development and behavior that are typically absent with proper nutrition and socialization in other species. Why then, does it take evidence from twin studies to make others realize that we are what we eat, and that our pheromones tell others who and what we are?
That’s the common theme across all of molecular biology, and the effects of a toxic environment are evidenced via my use of the honeybee model organism. What the queen bee eats determines her pheromone production and everything else about the interactions of the colony, including the neuroanatomy of the worker bees’ brains.
Does what one twin eats and the exposure to pheromones cause the neuroanatomy of the human brain to change? How could the epigenetic influences of nutrient chemicals and pheromones not be responsible for the differences in twins, and in everyone else? There’s no other model for those differences, and the molecular biology doesn’t change across species from microbes to man.read more June 29, 2012 • 5:58 PM
Where is the love?
The article I mentioned here on 3/12/12 is in the news, again.
Excerpt: “Love and sexual desire activate different areas of the striatum. The area activated by sexual desire is usually activated by things that are inherently pleasurable, such as sex or food. The area activated by love is involved in the process of conditioning by which things paired with reward or pleasure are given inherent value. That is, as feelings of sexual desire develop into love, they are processed in a different place in the striatum.”
My comment: An animal model is missing from this representation of how the conditioning of sexual desire develops into love. For example, model organisms are typically used to link “…things that are inherently pleasurable, such as sex or food…” to the development of pathways in the brain. These researchers claim that a pathway links love and sexual desire. Where’s the animal model or model organism for that?
Here it is! Pfaus et al., (2012) details how odors are responsible for sexual reward and bonding, which seem to merge in conscious awareness under the right circumstances (e.g., in humans) as romantic love. But the representation in Cacioppo et al, (2012) is one where viewing erotic pictures or looking at photographs of their significant others was used to form a complete map of love and desire in the brain. Are odors responsible for love and desire, or is it what we see?
A complete map of love and desire in the brain must have its basis in what is currently known about the molecular biology of brain development. Fortunately, there’s an animal model for that. For example, the neuroanatomist, Simon LeVay writes: “This model is attractive in that it solves the “binding problem” of sexual attraction. By that I mean the problem of why all the different features of men or women (visual appearance and feel of face, body, and genitals; voice quality, smell; personality and behavior, etc.) attract people as a more or less coherent package representing one sex, rather than as an arbitrary collage of male and female characteristics. If all these characteristics come to be attractive because they were experienced in association with a male- or female-specific pheromone, then they will naturally go together even in the absence of complex genetically coded instructions (LeVay, 2011, p. 210).”
I’ve taken this model of olfactory/pheromonal conditioning (Kohl, 2007), which LeVay summarized, even further in accord with the role of odors and rewards, which is consistent with Pfaus et al., (2012), but not consistent with the representation in Cacioppo et al, (2012). In “Human pheromones and food odors: epigenetic influences on the socioaffective nature of evolved behaviors” (Kohl, 2012), I detailed how the molecular biology that’s common to species from microbes to man allows nutrient chemicals and pheromones to influence reward-driven behavior in all species.
Unfortunately, there is no love in this model. But, if there were, it would be both the love of food and the love of other people. All reward mechanisms in my model are directly linked to behavior from the epigenetic effects of nutrient chemicals manifested in food odors, and the animal ‘chemistry’ of attraction manifested in pheromones. It’s food odors and pheromones that are responsible for our inherently pleasurable experiences with food or sex. Erotic imagery or looking at photographs cannot be used to map love and desire in the brain any more than a picture of food could be used to map the desire to eat or the ‘love’ of food. Showing how the brain lights up, does not show anything about the biology of cause and effect. (The end does not necessarily show the means.)
The map that’s required is one that must be based on what’s already known, which is that olfaction and odor receptors provide a clear evolutionary trail that can be followed from unicellular organisms to insects to humans. That map requires details of the neurophysiological mechanisms required to link sensory input from the environment directly to epigenetic effects on hormones that affect behavior.
If you want to know where love is, you can find out by following the path from your nose to the brain via the epigenetic effects of food odors and pheromones on hormone-secreting nerve cells, not one that somehow links pictures to love and sexual desire. There’s no model for that!
Cacioppo, S., Bianchi-Demicheli, F., Frum, C., Pfaus, J. G., & Lewis, J. W. (2012). The Common Neural Bases Between Sexual Desire and Love: A Multilevel Kernel Density fMRI Analysis. J Sex Med, 9(4), 1048–1054.
Kohl, J. V. (2007). The Mind’s Eyes: Human pheromones, neuroscience, and male sexual preferences. In M. R. Kauth (Ed.), Handbook of the Evolution of Human Sexuality (pp. 313-369). Binghamton: Haworth Press.
Kohl, J. V. (2012). Human pheromones and food odors: epigenetic influences on the socioaffective nature of evolved behaviors. Socioaffective Neuroscience & Psychology, 2, 17338 – DOI: 17310.13402/snp.v17332i17330.17338.
LeVay, S. (2011). Gay, Straight, and the Reason Why: The Science of Sexual Orientation: Oxford University Press.
Pfaus, J., Kippin, T., Coria-Avila, G., Gelez, H., Afonso, V., Ismail, N., et al. (2012). Who, What, Where, When (and Maybe Even Why)? How the Experience of Sexual Reward Connects Sexual Desire, Preference, and Performance. Archives of Sexual Behavior, 41(1), 31-62.
read more June 22, 2012 • 5:29 PM
Human pheromones and inner conflict about evolution (1102 words)
June 24, 2012, 5:00 pm 234 CommentsEDWARD O. WILSON
Excerpt with my emphasis: “Within biology itself, the key to the mystery is the force that lifted pre-human social behavior to the human level. The leading candidate in my judgment is multilevel selection by which hereditary social behavior improves the competitive ability not of just individuals within groups but among groups as a whole. Its consequences can be plainly seen in the caste systems of ants, termites and other social insects.”
My comment: “I should think we might fairly gauge the future of biological science, centuries ahead by estimating the time it will take to reach a complete comprehensive understanding of odor. It may not seem a profound enough problem to dominate all the life sciences, but it contains, piece by piece, all the mysteries.” — Lewis Thomas (1980) as cited in The Scent of Eros: Mysteries of Odor in Human Sexuality (1995/2002)
The force that lifted us from “pre-human social behavior to the human level” was predicted by Lewis Thomas, who allowed me to conclude more than three decades later that “Olfaction and odor receptors provide a clear evolutionary trail that can be followed from unicellular organisms to insects to humans (Kohl, 2012).” Wilson errs when he misses the apparent design in the biology of species that “…can be plainly seen in the caste systems of ants, termites and other social insects…” He apparently can’t see that the apparent design includes the role of pheromones in species from microbes to man.
The concept of “core words” is important here, which is why they are in bold typeface. My model details the ecological, social, neurogenic, and socio-cognitive niche construction that is required for adaptive evolution of species from microbes to man. The details include what is now known about the only pathway that links sensory input directly to behavior. That’s the gene, cell, tissue, organ, organ system pathway, and it starts with an absolute requirement for gene activation in cells.
Using core words makes my model sound complicated, so I uncomplicated the model by using the honeybee model organism as an example. Model organisms make core words easier to understand by placing them in their proper context. (more…)read more June 27, 2012 • 8:24 AM
Receptor-mediated biological cause and effect
Nature (supplement) Vol. 486, No. 7403 (). Produced with support from Ajinomoto Co., Inc.
“Taste is central to our being, but this vital sense is only now becoming clear at the biological level. Scientists have identified the receptors that respond to the five basic stimuli of sweet, sour, bitter, salty and umami (savoury), and are now exploring how the brain interprets them. Nature Outlook Taste reports the latest findings from the front lines of flavour.”
Here are links to the two articles from this supplement that I found most useful.
Taken together, these two open-access articles from the supplement offer a concise and reasonably accurate overview of the receptor-mediated events that are required for adaptive evolution. After reading 4 pages, it would be difficult for anyone who is vaguely familiar with biologically based cause and effect to attribute the required ecological, social, neurogenic, and cognitive niche construction of adaptive evolution to anything other than the epigenetic effects of olfactory/pheromonal input. There is, however, some misleading information on the role of random mutations. Evolutionary theorists can cling to that.
Unfortunately, the concision did not allow details of the evolved pathway in mammals that links food odors and pheromones directly to behavior via changes in intracellular signaling and stochastic gene expression in the hormone-secreting neurons of the medial preoptic area of the hypothalamus (e.g., in brain tissue). This neurogenic niche controls the development of every other neuronal system that is subsequently linked to behavior. For those details, you will need to read 7 more pages (with 3 pages of references). See, for example: Kohl, J.V. (2012) Human pheromones and food odors: epigenetic influences on the socioaffective nature of evolved behaviors. Socioaffective Neuroscience & Psychology, 2: 17338.
Nevertheless, reading only the 4 pages from the Nature supplement may advance the most vocal and errant of evolutionary theorists to a level of understanding about the importance of receptor-mediated events. This could lead further, perhaps even to an understanding of how animal models and model organisms are used to detail the adaptive evolution of behavior from microbes to man.
Anyone who can’t understand (e.g.,after reading 4 pages) why I focus on receptor-mediated events that cause adaptive evolution should remain silent to avoid letting others know how ignorant they are when it comes to the basic principles of biology and levels of biological organization required to link sensory cause to the adaptive evolution of human behavior.read more June 26, 2012 • 5:30 PM
Human pheromones and the viruses that make us
Excerpt: “On rare occasion, a retrovirus may infect an egg. Now something odd may happen. If the egg becomes fertilized and gives rise to a whole adult individual, all the cells in its body will carry that virus. And if that individual has offspring, the virus gets carried down to the next generation.”
I’m struck by the parallels with The Viruses That Make Us: A Role For Endogenous Retrovirus In The Evolution Of Placental Species by Luis P. Villarreal, which was brought to my attention by Greg Bear. Among his other excellent works, Bear wrote two science fiction novels that incorporated ERV-driven adaptive evolution, and pheromonal communication, which is as essential to communication in a new species of humans as it is in microbes.
Pheromones, as we now know, are the chemicals that control nutrient chemical-dependent reproduction in all species. It seems likely that ERVs, including human ERVs (HERVs) cause the changes in intracellular signaling and stochastic gene expression that allow us to use olfaction and odor receptors in the clear evolutionary trail that can be followed from unicellular organisms to insects to humans.
The HERVs, for example, need only alter a cell’s ability to metabolize nutrient chemicals (food) to cause downstream effects on every cell of any organism. The metabolism of the nutrient chemicals to pheromones does the rest in the context of adaptive evolution.
For those who question whether there is sufficient evidence across species for transgenerational epigenetic inheritance, one need only examine the trail that begins with the nutrient-dependent ecological niche of organisms. The metabolism of the nutrients to pheromones establishes a social niche. In multicellular organisms with a nervous system, ecological and social niche construction contribute equally to the construction of a neurogenic niche (a group of nerve cells) that enables brain development, which facilitates construction of our cognitive niche. My cognitive niche, for example, allows me to recognize patterns, like the design in biology that is apparent in the adaptive evolution that results from ecological, social, neurogenic, and cognitive niche construction.read more June 21, 2012 • 5:38 PM
Hacking the Genome
By Karen Hopkin | June 1, 2012
Excerpt: The biggest question of all: Is the genome like an exquisitely engineered Swiss watch, in which carefully crafted parts fit together perfectly and every feature is optimized to function flawlessly? Or, as Hurst puts it, “is it just some cheap Mickey Mouse watch that’ll tell you the time, but its components are poor-quality and it includes lots of crap that’s frankly unnecessary?”
My Comment: Rarely do we see evolutionary geneticists take a stand favoring the “exquisitely engineered Swiss watch” position that so often annoys evolutionary theorists. It is rarer still to see someone succinctly clarify this fact: “It was originally asserted that gene order in mammals is random. This was before anybody even had a complete eukaryotic genome, which was theoretical hubris taken to the nth degree.”
The arrogance of evolutionary theorists who have yet to learn anything about how natural selection continues to epigenetically alter our DNA via the effect of nutrient chemicals and pheromones is like a weight to be dragged forward into a new age of explanations coming from molecular biology.read more June 15, 2012 • 4:35 PM
Evolution of the nervous system: conserved GnRH
“Is the human brain just a lot more of the same stuff, or has it changed in a qualitative way?”
The most likely similarity is the role of glucose in the regulation of gonadotropin releasing hormone (GnRH) secreting neurons of the mammalian brain. Food deprivation suppresses GnRH-dependent pulsatile luteinizing hormone (LH) secretion in rats, sheep, monkeys and humans, which is consistent with inhibition of pulsatile GnRH release.
GnRH, is the molecule Kochman (2012) indicated was perfectly constructed because it hasn’t changed during the past 400 million years, although diversification of its receptor appears to allow for things like pheromone-dependent self / non-self recognition (at the advent of sexual reproduction, which requires a primitive immune system and means for sexual orientation).
GnRH also links nutrient chemicals and pheromones directly to adaptive evolution via the required ecological, social, neurogenic, and cognitive niche construction evidenced by the apparent design in biology.read more June 19, 2012 • 12:58 PM
A detailed model of physical reality and natural selection (722 words)
My knowledge of molecular biology, which is integrated into the physical reality of species from microbes to man, enabled me to model natural selection as the equivalent of a sensing agent. The moderator of the human-ethology yahoo group indicated this might be useful. “ I think it might be useful to consider natural selection the equivalent of a sensing agent. There could be things realized by doing this that would not be realized thinking about it in more conventional ways.”
My model is more useful for others if they first realize that nutrient chemicals and pheromones are responsible for adaptive evolution via natural selection. My model will not be useful to those who think more conventionally, for example, about how visual, auditory, or tactile input might cause natural selection because it is clear that they cannot cause natural selection.
It is equally clear that if nutrient chemicals are not sensed, the individual organism will starve to death, and if pheromones are not sensed, reproduction will not be controlled. The species may starve to death if the supply of nutrient chemicals is exhausted by overpopulation of the ecological niche. Starvation may exemplify natural selection, but it does not represent adaptive evolution.
Adaptive evolution is represented when nutrient chemical-dependent ecological niche construction leads to social niche construction by conspecifics. Ecological niche construction and social niche construction then contribute equally to neurogenic niche construction, which allows nutrient chemicals and pheromones to cause changes in intracellular signaling and stochastic gene expression in specialized hormone-secreting nerve cells that enable the development of the invertebrate brain via the effects of chemical input from the sensory environment on the brain’s hormone-dependent neuroanatomical structure and its function.
Nutrient chemicals and pheromones cause changes in intracellular signaling and stochastic gene expression in the hormone-secreting nerve cells of invertebrates, which is an effect on gene expression that extends to vertebrate brain development and construction of our cognitive niche (or as some have called it, our socio-cognitive niche). The term “socio-cognitive” niche attests to the likely role of social odors, called pheromones, as detailed in the eusocial honeybee model organism that I used to link species from microbes to man.
The concept of the socio-cognitive niche also addresses what Jay Feierman wrote about here: “…the perspective of natural selection, modeled as a brainless sensing agent…: What is physical reality is dependent upon the sensing agent.” Microbes and bees may not cognitively sense their physical environment, but nutrient chemicals and pheromones are part of the physical reality that must be sensed by all “sensing agents” in species from microbes to man.
I mentioned here that “In Human pheromones and food odors: epigenetic influences on the socioaffective nature of evolved behaviors I modeled natural selection as if it were a sensing agent for nutrient chemicals and pheromones.” I also restated that “Olfaction and odor receptors provide a clear evolutionary trail that can be followed from unicellular organisms to insects to humans.” It seems that then even Jay Feierman lost interest in what he said was his idea of “Modeling Natural Selection As If It Were A Sensing Agent.”
Indeed, after a very convoluted post Re: Physical reality and Natural Selection, Feierman seems to have changed his perspective on physical reality and natural selection because he wrote: “I’m using that as a foundation for talking about physical reality from the perspective of natural selection, when one is modeling natural selection as a sensing agent, which it is not (my emphasis). Does this sudden reversal of his idea to model natural selection as the equivalent of a sensing agent, as he indicated might be useful, mean that his idea is not to be considered useful in discussions of physical reality from the perspective of natural selection? Or does his sudden reversal mean that my model of natural selection as a sensing agent is not useful as a foundation when talking about physical reality.
Is there other physical reality for human behavior that is more important than the molecular biology I used in a model that incorporates what Feierman indicated was his idea of natural selection as a sensing agent? My idea is that nutrient chemical-dependent ecological niche construction and pheromone-dependent social niche construction contribute equally to the neurogenic niche construction that is responsible for adaptive evolution, development of the mammalian brain, and construction of our socio-cognitive niche.read more June 19, 2012 • 1:17 PM
Human Pheromones and Comparative Epigenomics
Excerpt: “While the genome of an organism contains all its genes, it is the epigenome that decides which are expressed, or “turned on.”
Article link: Comparative Epigenomic Annotation of Regulatory DNA
In a recent review article: Human pheromones and food odors: epigenetic influences on the socioaffective nature of evolved behaviors I detailed how the epigenetic effects of nutrient chemicals from the ecological niche cause social niche construction via the metabolism of the nutrients to pheromones, which control reproduction and diversity in species from microbes to man. In mammals, the ecological niche and social niche contribute equally to construction of the neurogenic niche responsible for our cognitive niche.
It should surprise no one that nutrient chemicals and pheromones are responsible for the development of the mammalian brain that enabled construction of our cognitive niche. For example, I used the honeybee model organism to detail how what the queen eats determines the production of her pheromones that are responsible for everything that influences the behavior of the colony, including the neuroanatomy of the worker bees’ brain.
What surprises me is that anyone would dispute the significance of modeling behavioral development across the ecological, social, neurogenic, and cognitive niche construction domains by incorporating the epigenetic effects of nutrient chemicals and pheromones on intracellular signaling and stochastic gene expression. Not only do these epigenetic effects directly connect the sensory environment to the development of behavior, but they do so via the conservation of gonadotropin releasing hormone and diversification of its receptor-mediated events. The obvious conclusion is “olfaction and odor receptors provide a clear evolutionary trail that can be followed from unicellular organisms to insects to humans.”
Does anyone think a different conclusion is likely to result from the comparative epigenomic annotation of regulatory DNA or of non-coding ‘junk’ DNA? In my model the ‘junk’ must be there to allow production of the de novo olfactory receptors required for adaptive evolution. If I’m wrong, is there another model for that? If nutrient chemicals and pheromones do not cause the changes in intracellular signaling that cause the stochastic gene expression required for individual survival and the reproduction of species, what sensory cause does result in direct effects on gene expression and adaptive evolution in species from microbes to man?
We can only hope that as works like the one linked above proceed, that similarities and differences in species are considered. My preference is for more consideration of the similarities across species from microbes to man that are apparent in their common molecular biology.read more June 12, 2012 • 7:15 PM