Nutrient chemicals cause ecological niches to form that enable interactions among the conspecifics of social niches. Nutrition and pheromones are both required for epigenetic effects on development of a neurogenic niche in the honeybee brain and a hypothalamic neurogenic niche in the mammalian brain.
This fact can be explained to a general audience by saying that food odors cause us to eat what causes us to produce pheromones that cause us to associate, or not associate, with other people. In this context, pheromones are social odors.
…one-way models of evolved complexity don’t work for me, but especially when the “one way” is via degradation.