Natural Selection Is Still With Us
“Courtiol is not certain how strong natural selection is today, particularly in the developed world. But he says that at the very least, the data show that even as recently as 200 years ago, it still played a role in shaping humans as a species. As such, he notes, biological and cultural processes should both be considered in understanding how humans are changing through time.”
Background: Cultural processes are biologically based.
Explanation: Nutrient chemicals calibrate intracellular signaling and stochastic gene expression that establishes diversity in ecotypes (i.e., in the organisms that do not die of starvation). The metabolism of nutrient chemicals to pheromones that standardize and control intracellular signaling and stochastic gene expression establishes diversity in ecotype-dependent social niches, which are the basis for the development of culture.
Problem: Ignoring the molecular biology common to all organisms from microbes to man makes it appear that biological and cultural processes operate somewhat independently across species — as if there were significant differences in the molecular biology of different species. Instead, the significant differences are in the availability of nutrient chemicals and in the pre-existing genetic variation that 1) contributes to the metabolism of nutrients to pheromones; that 2) control species-specific reproduction, that 3) makes it appear that cultural processes should be considered outside the context of the basic principles of biology and levels of biological organization required to link sensory stimuli from the environment directly to changes in pre-existing genetic variations.
Solution: In the past few years, the importance of sexual selection for chemosensory cues, which are called pheromones, has been demonstrated in birds and in fish to be a requirement for adaptive evolution as it is in other species that sexually reproduce, including humans. The cultural denial of human pheromones is akin to denying that food odors do not exist, because — as I said — nutrient chemicals calibrate... and pheromones standardize and control species survival via the same molecular mechanisms.