r/K Selection Theory

Biologists have long noted that species will tend to evolve behaviors which best aid them to effectively exploit their environment. Among these behavioral life history traits are reproductive strategies. Reproductive strategies are, as the name implies, the strategies individuals will use to reproduce. Here we will focus upon the two strategies demonstrated in r/K Selection Theory in Evolutionary Biology.

The science behind r/K Selection theory was hashed out decades ago. It emerged as biologists pondered why some species reproduced slowly using monogamy and high-investment parenting, while other species reproduced explosively, using promiscuity and single parenting. At the time this science was developed, the researchers were wholly unaware of its relevance to our modern ideological battles in the world of politics. The terms r and K came from variables in equations which described how populations would change over time. r represented the maximal reproductive rate of an individual, while K represented the carrying capacity of an environment.

r/K selection theory describes two environmental extremes, and the strategies a population will produce to exploit each extreme. As a result of these strategies, each of these two environments will produce a very particular psychology in the individuals exposed to them.

The first environment an organism may face is the presence of freely available resources, which is referred to as an r-selective environment. This most often occurs when a predator keeps a population consistently lower than the carrying capacity of its environment. Just as rabbits do not strip their grassy fields bare due to the predation they endure, the r-strategy is designed to exploit an environment where resources are freely available, everywhere.

In r-selection, those individuals who waste time fighting for food will be out-reproduced by pacifists, who simply focus upon eating, and reproducing. Fighting also entails risks of injury or death – risks which are pointless given the free availability of resources everywhere. Hence this environment will favor a tendency towards conflict avoidance, and tend to cull the aggressive and competitive. It will also evolve tendencies towards mating as early as possible, as often as possible, with as many mates as possible, while investing as little effort as possible rearing offspring. Here, there are unlimited resources just waiting to be utilized, and even the most unfit can acquire them. As a result, it is more advantageous to produce as many offspring as possible, as quickly as possible, regardless of fitness, so as to out-reproduce those who either waste time producing quality offspring or waste time competing with each other.

Since group competition will not arise in the r-selected environment, r-type organisms will not exhibit loyalty to fellow members of their species, or a drive to sacrifice on their behalf. Indeed, the very notion of in-group will be foreign, and the concept of personal sacrifice for other in-group members will be wholly alien. This is why rabbits, mice, antelope, and other r-selected species, although pleasant, will tend to not exhibit any loyalty or emotional attachment to peers. When resources are freely available, group competition is a risk one need not engage in to acquire resources, so this loyalty to in-group and emotional attachment to peers is not favored.

Here in the r-strategy, we see the origins of the Liberal’s tendencies towards conflict avoidance, from oppositions to free-market capitalism, to pacifism, to demands that all citizens disarm so as to avoid any chance of conflict and competition. Even the newer tendencies to support the ”everyone gets a trophy” movement are outgrowths of this competition-averse urge, and desire for free resource availability. Similarly, Liberals are supportive of promiscuity, supportive of efforts to expose children to ever earlier sexual education, and, as the debate over Murphy Brown showed, Liberals are supportive of low-investment, single parenting. Finally, as John Jost has shown, Liberals show diminished loyalty to in-group, similar to how r-selected organisms do not fully understand the reason for even perceiving an in-group in nature.

In the other environment, a population exists at the carrying capacity of its environment. Since there is not enough food to go around, and someone must die from starvation, this will evolve a specific psychology within such a species.

Termed a K-type psychology, or K-Selected Reproductive Strategy, this psychology will embrace competitions between individuals and accept disparities in competitive outcomes as an innate part of the world, that is not to be challenged. Since individuals who do not fight for some portion of the limited resources will starve, this environment will favor an innately competitive, conflict-prone psychology. Study shows, such a psychology will also tend to embrace monogamy, embrace chastity until monogamous adulthood, and favor high-investment, two-parent parenting, with an emphasis upon rearing as successful an offspring as possible. This sexual selectiveness, mate monopolization, and high-investment rearing is all a form of competing to produce fitter offspring than peers. This evolves, because if one’s offspring are fitter than the offspring of peers, they will be likely to acquire resources themselves, and reproduce successfully.

Although total numbers of offspring will be diminished with this high-investment rearing strategy, the offspring’s success in competition is what is most important in a K-selective environment. Here, wasting time producing numerous offspring that are not as fit as possible will doom one to Darwinian failure. As time goes on, and K-selection continues, forming into competitive groups will often emerge as a strategy to acquire resources. This will add add loyalty to in-group to the suite of K-type psychological characteristics. This is why when we look at K-selected species in nature, we see packs of wolves, herds of elephants, prides of lions, and pods of dolphins, and each individual is loyal to their group and its competitive success. Since the only way to survive will be to acquire one’s resources by out-competing peers, this invariably produces tremendously fast rates of evolutionary advancement. For this reason, K-selected organisms are usually more evolutionarily advanced than their r-selected counterparts, and will exhibit more complex adaptations, from increased intelligence and sentience, to increased physical capabilities, to loyalty and prosociality, in species where group competition occurs.

Clearly, this mirrors the Conservative’s embrace of competitions, such as war, capitalism, and even the bearing of arms in self-defense against criminals. It also mirrors the Conservatives tendency to favor family values, such as abstinence until monogamy and two-parent parenting. It even explains why Conservatives feel driven to see their nation succeed as greatly as possible, regardless of the effects this has upon other nations or just members of their out-group.

To my eye, it is inherently clear that this r/K divergence is the origin of our political divide. Indeed, while policy proposals from Conservatives are predicated upon the premise that resources are inherently limited, and individuals should have to work and demonstrate merit to acquire them, Liberals advocate on behalf of policy proposals which seem to be predicated upon an assumption that there are always more than sufficient resources to let everyone live lives of equal leisure. To a Liberal, any scarcity must clearly arise due to some individual’s personal greed and evil altering a natural state of perpetual plenty.

Here, we see how these two deeply imbued psychologies generate grossly different perceptual frameworks within those who are imbued with them. Just as a Liberal will never grasp why a Conservative will look down upon frequent promiscuity and single parenting, the Conservative will never grasp why the Liberal will be so firmly opposed to free market Capitalism, or the right to self defense when threatened. Each sees an inherently different world, and is programmed to desire an inherently different environment.

In nature, since it is the individuals who best exemplify this r-selected psychological standard who will reproduce under conditions of resource abundance, their offspring will carry these traits. As time goes on, the population will gradually develop ever more extreme presentations of these traits. As we show, there is copious evidence that a genetic allele, which diminishes dopamine signaling, is associated with every facet of the r-strategy’s psychology, as well as a predisposition towards political Liberalism.

In addition, the r-strategy may have evolved to be engendered within individuals by environmental stimuli as well, through a desensitization to the neurotransmitter dopamine. This effect arises from its copious release in such an environment down-regulating receptor expression and consequently reducing receptor densities in nervous tissue. We also maintain that a lack of adversity in the environment will fail to develop a drive or ability to confront adversity, through a failure to develop a brain structure called the amygdala. In summary, an organism placed in an environment devoid of adversity, and filled with pleasure, may find itself more demanding of pleasure and less tolerant of adversity, than an organism which is enured to a less hospitable environment.

Within r/K selection theory, all populations will contain some differing degrees of r and K selected psychologies. As an environment shifts to one extreme or the other, a population will adopt a more r or K-selected psychology, but this will only last as long as the environmental conditions which produced the shift continue. Under conditions of reduced mortality, and copious resource availability, both r and K-selected psychologies will be present. This will continue until such time as resources become limited, and a competitive, K-selected pressure takes hold, or predation begins to cull both sides evenly, and the K-selected individuals, being slower reproducers are relatively culled back.

Interestingly, r/K Theory not only explains a means by which our political ideologies are adaptive to a specific environment. Many have noted an increasingly masculine quality to the women in our culture, as well as a corresponding effeminate nature to our men. Rush Limbaugh will often refer to them as the Feminazis, and the Castrati. In nature, a K-selected model of rearing involves a feminine mother, who nurtures offspring and guides them away from danger, combined with a more masculine male who will aggressively confront dangers, so as to protect his family.

However, when a population becomes increasingly r-selected, the nature of the sexual dimorphism and these sex-specific rearing behaviors will change. As you see a more r-strategy emerge, females of the species will need to become increasingly aggressive and masculine, since due to paternal abandonment, they must provision and protect their offspring alone. Since r-selected males are solely concerned with mating (before abandoning their mate), and fleeing from conflict, they become more diminutive, and more cowardly. The end result is the r-strategy has, inherent within it, a model of aggressive, manly females who raise children alone, and diminutive, effete males who are solely concerned with superficial, mate-attracting flash, and conflict avoidance.

Even more interestingly, as we point out in this blog post, as well as this blog post, there is evidence indicating that this phenomenon, accidentally over-expressed, may be responsible for producing males who are so effeminate that they are actually homosexual, and females who are so manly, they cross the boundary into lesbianism. Not only do the rearing behaviors and sexual characteristics change, but the males become attracted to more manly characteristics (which are now exhibited by the most adaptive females), and the females become more attracted to effeminate characteristics (which are now exhibited by the most adaptive males).

Some will ask, why would we have evolved both of these psychologies, within our species, instead of trending totally r or K. This can occur for a number of reasons. Obviously an organism which inhabits an environment where resources surge in availability, and then become scarce can see its r-types surge in number during times of plenty, only to die back once resources become scarce. Indeed, such a population may eventually see its individuals adapt to change their strategy with the availability of resources. Or, as time goes on, the r-types may evolve strategies designed to see a few members persist during times of scarcity, so they may explode again once resources become plentiful.

But in humans, the mechanism was probably a little more complex. When we first evolved, a critical adaptation was our loss of body hair. It allowed us to move about in the heat of an African day, when all other furred prey needed to bed down. To acquire meat, all we needed to do was roust a bedded down antelope, make it run a short distance, and it would rapidly collapse of heat stroke, so we could then acquire its meat. There are tribes in Africa who still hunt using this method.

This allowed us to explode in numbers, but as in all ecosystems, we eventually found there were not enough resources to support the population. It was at this time that our population divided.

At this point, the competition was fierce. One group adopted the K-selected psychology, stayed put, and slugged it out for resources, in free, merit based competition. They formed into groups, battled for territory and resources, and adopted a competitive, K-selected reproductive strategy. They became the K-type cohort of our population, embracing freedom and self-determination, free competition, monogamy, strong family values, loyalty to in-group, and sexual chastity in the youth.

As the battles began to rage, another cohort, more cowardly and weak, fled. Those who fled the fastest and the farthest, found themselves in a new, untapped territory, with free resource availability yet again. Those among them who did the best from Darwin’s perspective, were those who adopted the most r-type strategy of free promiscuity, single parenting, and early age at first intercourse. They had no need for loyalty to in-group, and indeed, would have adopted a more selfish and cowardly psychology, to better disperse their genes, and serve their own self interests. They became our population’s r-type cohort, and even today, the gene which is associated with Liberalism is found in large numbers in migratory populations, even as social psychologists note that Liberals score highly in novelty seeking, such as preferring new and novel environments, or unusual foods.

As time went on, Homo sapiens likely spread across the globe in this manner. r-types fled as the territory behind them became K-selective and competitive. As time went on, this constant selective pressure favoring fleeing gradually made the r-type more prone to flee competitions and adhere to an r-type mating strategy, and less able to even comprehend why K-types would ever seek monogamy or aggression when threatened, or innately perceive an in-group in need of defense.

In between where the r-types fled to, and where the K-types were battling it out, there was likely a sort of geographical spectrum. At one end were the extreme r-types on the frontier, and at the other were the extreme K-types, battling with neighbors. But in the middle, were areas where some r-types were mingling with some K-types. It is likely that there, these two strategies were evolving psychological traits which would allow them to persist in a mixed population. K-types tried to purge the disloyalty, selfishness, and promiscuity of the r-types, while r-types tried to use deception, as well as the rule-breaking and lack of loyalty identified by Jost (himself a Liberal), as an advantage. It would not surprise me if our political animus was evolved.

It is also interesting to note, even today, as r-types gain hold in a civilization, they seek to provide the unproductive and uncompetitive with the free resource availability of the r-selected environment. As in nature, as this goes on, the r-type cohort grows in the population, until the entire financial ecosystem collapses, the government dissolves, and the civilization becomes ruthlessly competitive. As in nature, free resource availability cannot go on forever.

To be clear, individuals are complex. Just as it is difficult to characterize a single individual organism’s exact reproductive strategy in nature, it is difficult to characterize a single human’s political strategy. However, just as the quantum mechanical world yields the chaos of its uncertainty to the order and formality of Newtonian physics when viewed from a distance, as we zoom out from our society we will find two primary ideologies within it. Just as in nature, these two ideologies match exactly the two psychologies of the r and K-type psychology.

Before closing, I would like to note that the primary environmental condition favoring an r-strategy is free resource availability. Too often the r-strategy is portrayed as a defensive adaptation designed solely to overcome the mortality of predation, or other forms of environmental harshness, through increased reproductive rates. The r-strategy however, is just as much an offensive adaptation designed to exploit free resource availability, and the absence of competitive selections for survival and reproduction.

In the book, we describe how this may be seen most clearly in the world of microbiology. There, complex, highly-adapted microbes are often drawn from a harsh, highly selective environment, and transferred to an unselective environment of ideal conditions and free resource availability (such as a petri dish of nutrient media housed in an incubator). There, they initially grow slowly, as each parent cell carefully produces colonies full of highly adapted daughter cells.

Some parent cells however, make mistakes, and produce less complex offspring, who reproduce more rapidly, as they devote less energy to their parent cell’s complex adaptations. As time goes on a highly evolved isolate can quickly shed its adaptations and devolve into a strain of simpler, less complex cells which grow colonies astonishingly quickly on agar. Over time, if given only free resource availability, the cells of the simpler dysgenic strain will numerically dominate any peers which retain their complexity and adaptation. In this environment, due to the absence of competitive selections favoring fitness or complexity, the sole determinate of survival becomes sheer numerical advantage. As a result, it is this standard which the organism will evolve towards, and one will increasingly find a less complex, less evolved organism devoted solely to mating and reproduction. Free resource availability, and an absence of competitive selection pressure, by itself, is all that is necessary to fuel a rapid growth in the r-strategist cohort within a population.

In closing, it is impossible to deny that every aspect of political ideology revolves around the same fundamental issues of behavior that r/K selection theory revolves around. Although our species’ embrace of group competition has further molded these urges, this is the evolutionary foundation of ideology. It is where political ideology began. For that reason, no individual can ever fully understand political ideology or the forces which motivate it, absent a grasp of r/K Selection Theory.

If you found this information interesting, please consider our plea for virality, on our front page. This information has the potential to greatly enhance our political dialog, and aid in the pursuit of freedom. But I cannot tell everyone about it all by myself. For it to go viral, I need the reader’s help. Please try to find two people who will spread this, and show it to them. I will be eternally greatful.

For more on r/K Selection Theory please see :

Pianka, E. R. (1970). On r- and K-selection. American Naturalist, 104, 592–596.

MacArthur, R., Wilson, E. (1967). The theory of island biogeography. Princeton, NJ: Princeton University Press.

Also, please see the first chapter of our sample text, The Theory Behind this Book, where we describe the mechanisms underlying r/K selection in nature.