Ecological adaptations and the origin of lactase persistence

Genetic Origins of Lactase Persistence and the Spread of Pastoralism in Africa

Reported as:

Origins of Lactase Persistence in Africa

Large-scale sequencing effort confirms several mutations that confer lactase persistence in Africans, while haplotype analysis sheds light on the trait’s origins.

By Ashley P. Taylor | March 13, 2014

Excerpt: “Tishkoff and her colleagues identified three known variants…”

My comment: Journalists consistently report that  variants are mutations. Experimental evidence and everything currently known about conserved molecular mechanisms in species from microbes to man show that the variants are nutrient-dependent ecological adaptations.

For example, the link from fermented milk products to vitamin D-induced changes in base pairs, amino acid substitutions and epialleles that stablize the organized genome of human populations is clear. Thus, lactase persistence can be considered in the context of the hemoglobin S variant associated with endemic malaria and sickle cell disease.

Otherwise, journalists may continue to ignore what researchers know about the difference between a mutation and an ecological adaptation. Like the variants reported here, hemoglobin S is a nutrient-dependent ecological adaptation.

Variants associated with nutrient-uptake typically result in reproductive fitness, which is why they show up in different populations. Attributing reproductive fitness to mutations is confusing.

The missattribution may also cause people to think that human population-wide differences associated with skin pigmentation are due to mutations, at a time when molecular biologists realize that ecological variation and ecological adaptations are responsible for morphological and behavioral phenotypes.

Only evolutionary theorists, or those who have been taught to believe in the theory, continue to attribute ecological adaptations to mutation-driven evolution.

 

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