Is humanity undergoing a transition to reproductive specialization? Insights on the evolution of modern societies to superorganisms

Edwin F. Herrera-Paz, COCINH-LAB Honduras, Gobierno de la República de Honduras, Tegucigalpa MDC; Faculty of Medicine, Universidad Católica de Honduras, Campus San Pedro y San Pablo, San Pedro Sula. Honduras

A current discussion centers on whether human societies are undergoing a major evolutionary transition in individuality (METI) toward superorganisms. A METI typically involves a population composed of independent units evolving to form a new unit of a higher level of complexity, as for instance, the emergence of multicellular organisms from unicellular organisms, or the evolution of superorganisms, such as beehives. It has been proposed that for a METI to occur, certain key criteria must be met, including division of labor, exponential increase in size, inseparability, and reproductive specialization. All of these characteristics have been documented in human populations over the past 12,000 years, except for reproductive specialization. This involves that only a fraction of the population carries out reproductive functions, while the rest performs maintenance tasks. Recently, human populations are experiencing the so-called “demographic transition,” characterized by a decrease in infant mortality, followed by a decrease in birth rates. The causes of this transition are mainly sociocultural, leading to diminished reproductive competition, which, in turn, could lead to biological infertility. This begins a positive feedback loop of declining fertility, potentially leading to a demographic winter and the risk of extinction of modern societies. To prevent such an outcome, governments will probably implement rescue measures that could lead to reproductive specialization. The study of transitions has medical importance because they may cause shifts in health-disease landscapes.