By Edyta Zielinska
Humans can tell the difference between the body smells of the young and the old, and find that youth is smellier.
Nutrient chemicals in the ecological niche calibrate individual survival, and the nutrient chemicals metabolize to pheromones in the social niche, which standardize and control reproduction in all species. Ecological and social niche construction also are required for adaptive evolution. For example, the construction of ecological and social niches results in epigenetic effects of food odors and pheromones on the hypothalamic neurogenic niche responsible for mammalian brain development and behavior. This exemplifies the design that is apparent in biology. That is, the transgenerational epigenetic inheritance of the molecular mechanisms for food preferences and social/kin preferences are manifestations of the common molecular biology of organisms from microbes to man.
Given the fact that body odors (social odors called pheromones) convey social cues that are as important as food odors to species survival in all species, it should surprise no one that we can detect differences in age via these olfactory/pheromonal cues. How could this not be the same in humans as in every other species that can detect the differences in aged foods and aged conspecifics. Food odors and pheromones classically condition our response to the visual appeal of food and conspecifics as occurs in all other animals. It’s nice to see the data that prove another aspect of this model for species survival, but to many people it’s common sense. Isn’t it? You’re not likely to eat something that doesn’t smell right, or mate with anyone who doesn’t smell right. The common sense that ensures that is olfaction.