Blazing Genomes
The Genetic, Epigenetic, and Cultural Drive of Conservatism
by Charles Brack
Welcome to Rock Ridge, Sheriff Obama
The hypothesis that political conflict in a population increases proportionately with genetic divergence is ultimately founded upon selfish gene theory. Selfish gene theory simply states that the gene is the fundamental unit of natural selection, and not the individual organism (phenotype), or genome. While Darwin and the founders of population genetics, Ronald Fisher, John Haldane, and Sewall Wright, all implied this reductionist viewpoint, Colin Pittendrigh (1958) was the first to explicitly propose it, which was subsequently formulated by George Williams (1966) as genic selectionism, and popularized by Richard Dawkins (1976) as The Selfish Gene.
The argument for genic selectionism is compelling: organisms were phenotypes that only lasted until they died, while their genomes were broken up by meiosis and recombination. Even though phenotypes and genomes were being acted upon by natural selection, the only thing that survived the death of the phenotype, intact, were the genes. As we shall see, the theory of genic selectionism is being complicated by the growing evidence that non-coding regions of DNA are indeed performing valuable evolutionary functions. Further, cloning could be interpreted as genomic selectionism, and of course, a competitor to genic selectionism.
Gene competition, or genetic drive, occurs at all levels of biological interaction: genes within a genome; cells within an organism; organisms within a population; populations within a species; and, between species. While the most well-known method for a gene to replicate itself into the future is to confer some sort of adaptive advantage to its host organism, there are more sinister methods, which have some striking similiarities to the many diverse competitive behaviors in humans.
At the genome level, at least three mechanisms of gene selfishness are at play: overreplication, interference, and gonotaxis (see Burt and Trivers discussion, 2006). Overreplication is the ability for a gene to disproportionally replicate itself relative to other genes in the same organism. Genes accomplish this in a myriad of ways: encoding their own DNA polymerase (which constructs a new DNA segment from a template segment); breaking chromosomes to be subsequently replicated during repair; and jumping to other locations during DNA replication to get copied more than once. At the organism level, overreplication is equivalent to rapid reproduction.
The selfish gene at work: Down syndrome typically occurs due to a nondisjunction of chromosome 21 during gametogenesis, an example of the genetic drive of "getting into the germline". This event usually happens with female gametogenesis during the later reproductive years. Despite Sarah Palin's large family, there is no current evidence that highly reproductive females are at greater risk for conceiving a Down syndrome child.
Secondly, gonotaxis involves the preferential movement of a gene to the genetic material that is designated for reproduction, known as the germline. As an example, female meiosis results in one egg and two to three polar bodies, providing an opportunity for a selfish gene to use chromosomal knobs, as in maize, to get into the egg ahead of potential rivals. Getting to the germline is where immortality happens for the selfish gene, as any mutation that arises in a somatic cell will not be transferred to the next generation, and likely only experience 30-90 mitotic divisions before expiring.
Thirdly, a large class of genes interfere with the replication of other genes, chromosomes, or entire sets of chromosomes. This behavior is emulated in animals in a variety of ways, such as animal dominance behavior, where dominant animals typically interfere with the reproduction of subordinates. While genes engage in many innovative ways to promote themselves at the expense of their rivals, almost all of their tactics have corrollaries at the organism level. Political-religious behavior is simply one more expression of this fundamental conflict between genes. In humans, this has three Darwinian consequences: genetic, epigenetic, and cultural drive.
What is Genetic Drive?
The Hardy-Weinberg principle states that gene frequencies remain stable in a population from generation to generation without the disturbances of mutation, non-random mating, and selection. In other words, it never applies to animal populations for very long. Population gene frequencies are constantly under the pressure of drive, that is, genes are constantly changing their numbers and proportions within a population.
Genetic drive is the collection of processes that change gene frequencies in a population. As previously mentioned, it occurs at all levels of biological interaction: genes within a genome; cells within an organism; organisms within a population; populations within a species; and, between species.
While we have just described some of the ways genes compete within a genome, genes are also the driving force behind the constant political-religious conflict that has plagued the human species for tens of thousands of years. Genetic drive at the genome level is accomplished during intracellular molecular interaction. At the organism level, it occurs primarily via variation in: reproductive rates; inclusive fitness; exclusive fitness or spite; habitat dynamics; and, life span.
Conservatives and liberals are the most vocal of the political cohorts, and not surprisingly, create disproportionately high levels of genetic and cultural drive in any population. Let's take a closer look at how the conservatives have been executing their particular flavor of genetic drive, and leaving a trail of culture to support it.
The Genetic and Cultural Drive of Conservatism
Let's restrain our conversation to Caucasians only, and entertain the proposal that conservatism, on average, creates greater genetic drive in three biological levels of interaction: between individuals, between populations, and between species. The primary behavior that leads to this proposal is reproduction, which is substantially elevated in conservatives.
In the United States, Caucasian conservatives significantly outreproduce Caucasian liberals (our estimate ranges from 40-55% more offspring), which provides them with their substantial genetic drive. This, of course, implies that conservatives have slightly different gene frequencies than liberals, which is inferred by twin studies of political affiliation (Alford, 2005).
This conservative genetic drive is reflected in their cultural drive, which is founded upon several political-religious attitudes and behaviors: anti- abortionism and gay marriage; elevated sense of threat from outgroups; preference for smaller social groups; lowered restrictions on economic behavior; higher levels of male dominance and male reproductive success; a stronger orientation to the production of energy; aversion to national health care and taxes; greater need for space and higher rates of reproductively-induced dispersal; lower rates of altruism towards genetic distance; increased levels of pair-bonding and monogamy; and, a greater tendency towards reproducing within their own race.
The common Darwinian theme to all of the above attitudes and behaviors is: accelerated reproduction over a smaller genetic bandwidth. Religious conservatives, the most reproductive of all the political-religious cohorts, promote these cultural drives, highlighting the close Darwinian relationship between conservatism, religiosity, and reproduction.
The elevated sense of threat that conservatives maintain towards outgroups most likely originates from phylogenetically ancient reproductive behavior, whereby animals with offspring maintain an elevated sense of threat towards strange animals. Further, the neurology associated with xenophobia seems to be closely linked with reproductive effectiveness.
L=Liberal, M=Moderate, C=Conservative
F=Female, M=Male
Are you more empathetic towards babies or adults? Conservatives report a greater empathy differential between babies and adults than do liberals. In this graph, 1,703 people were asked to rate their relative empathy for babies versus adults on a scale of -5 to 5 (0 = no difference in empathy between adults and babies). The higher the score, the greater the empathy difference in favor of babies.
It is interesting to note that people with conservative political dispositions have both elevated startle eyeblink responses to loud unexpected noises and greater changes in skin conductance to threatening visual images (Hibbing, 2008). Elevated startle eyeblink response is associated with amygdalar activation. This hints at a potential conservative-left hemispheric connection, as Phelps (2000) found that the presentation of black faces to white subjects induced an elevated startle eyeblink response and an elevated activation of the left amygdala.
The amgdala's multiple roles in responding to perceived threats and promoting sexual behavior may be the connection between the conservative attributes of elevated threat from strangers and fertility. In particular, the medial region of the amygdala is involved in olfaction, sexual arousal, and motor activity associated with executing sexual behaviors. The medial region is sexually dimorphic, and if stimulated, can induce ovulation, uterine contractions, lactation, and lordosis in females.
The female medial amygdala is a principle site of estrogen uptake, and adjusts immune system activity during the menstrual cycle. In males, the medial amygdala can trigger penile erection and male-specific sexual behavior. In males, the amygdala is larger, synaptically more diverse, and changes in response to variations in testosterone levels. The medial amygdala projects directly into the ventromedial and preoptic areas of the hypothalamus, which coincidentally, are also sexually dimorphic. There is indeed evidence that the left amygdala, which is more elevated in responding to black faces, also participates more in the initiation of sexual behavior than the right amygdala.
The Genetic Drive of Capitalistic Deregulation
Besides warfare, capitalism may be the single greatest instigator of genetic drive the human species has ever seen. Capitalism works its genetic magic by taking advantage of both resource and reproductive-energy differences between populations, building easier modes of travel between those populations, and in the long run, substantially changing the gene frequencies of those connected populations.
But of particular contemporary interest is the genetic drive associated with capitalistic deregulation, which is more likely to be promoted by conservatives and libertarians than liberals. It is certainly arguable that the number of economic restrictions on a population is inversely proportional to the change in gene frequencies in that population. That is, a population with fewer socioeconomic controls creates greater genetic drive than a population with many controls. However, this is just speculation, and there indeed may be many instances where the reverse is true.
It is interesting that male reproductive effectiveness is directly proportional to income, and therefore, the Darwinian advantages of "cheating" or otherwise unethical behavior can be substantial. Males are more likely to engage in both criminal activity and unethical business practices, and further, more likely to favor the deregulation of economic behavior. The high level of competitiveness in the workplace is just one more battleground of genetic conflict.
The Genetic Drive of Tax Rates, Income Redistribution, and Health Care
An argument can certainly be constructed that the redistribution of income via taxation can alter or maintain population gene frequencies in favor of those individuals that benefit from the redistribution. This presumably works by improving reproduction and life expectancy in the recipients, but only if the genetics of the recipients were, on average, different from the general population. While this can only be indirectly inferred, it seems to be true for most nations with tax systems that are redistributive.
Interestingly, redistribution of wealth via the tax system is a common countermeasure employed to reduce the severe impact that capitalism has on population genetics. Capitalistic downturns can be catastrophic for the genetics of the poorest social groups in the economy. Redistributions of income tend to favor female reproduction, and generally follow the tendency for declining human populations to devote disproportionately more resources towards reproductive females.
Historically, in the United States, welfare payments have disproportionately benefited non-white genetics, which is at least a partial neutralization of the legacy of racially-motivated economic discrimination from the white population. Further indicating the underlying genetic competitiveness associated with taxes and the redistribution of income, among white Americans, support for welfare programs are inversely proportional to the degree of one's racist tendencies (Schram, 2003).
The genetics of tea bag parties: taxes suddenly become an issue when a non-white president takes power
In 2007, the percentage of Caucasians in the United States covered by health insurance was greater than that of Blacks (90% to 80%), according to the US Census Bureau. Further, the percentage of insured Asians was 83%, while Hispanics had the lowest rate, at 68%. The genetic impact of national health care would favor non-Caucasian reproduction and life expectancy and therefore non-Caucasian genetics in the gene pool. It is therefore no surprise that Caucasians are more likely to be against it. The Caucasians have a lot at stake with their health care advantage, as they have lower life expectancies than either the Asian or Hispanic populations.
Inclusive Fitness, Reproduction, and the Altruistic Conservative
Conservatives and liberals have certainly presented a lot of contradictory evidence as to which group is more altruistic. The conservative case for higher rates of altruism is strong (Brooks, 2006), although correlation between conservatism and charitable contributions, when controlling for religiosity, is negligible. Religiosity is the most highly correlated variable with charitable contributions, regardless of political affiliation.
Since religiosity is highly correlated with conservatism, the conservatives can claim a distinct advantage in the war of altruism, due primarily to religious tithing. While there is good reason to believe that conservative altruism is greater than liberal, there is also good reason to believe that it is distributed across lower genetic distance.
These two dimensions of conservative altruism are a byproduct of reproduction, which is substantially elevated in conservatives. The altruistic investment that parents devote to offspring is a considerable burden to conservatives, and further, constitutes altruism over lower genetic distance. Further, the religious are substantially elevated in their charitable contributions due to tithing, which tends to be more locally distributed within the local church and community.
The conservative tendency to be against redistributive tax policies, national health care, and environmentalism are fodder for liberal claims of "mean-spirited" conservativism. However, given the increased burden of reproduction on conservatives, their altruism will be focused across lower genetic distance.
What Genes does Conservatism Select For?
Altruism's evolutionary secret is that the selfless sacrifice of one's genes is compensated by a corresponding increase in fitness of the same genes in other individuals. In other words, altruism is fundamentally selfishness at the level of the gene. The most common example of altruism is the amount of energy a parent devotes to offspring, even though the parent has only contributed 50% of the offspring's DNA.
Interestingly, the altruistic investment in offspring tends to increase with the cognitive capacity of the species. The brain is an energy-intensive organ, and requires progressively higher levels of parental altruism to support its slow development. Therefore, species with greater cognitive capacity tend to exhibit higher rates of altruism.
The traditional argument for altruism revolves around the coefficient of relatedness, which is the percentage of genes shared by common descent. The great population geneticist, JBS Haldane, first remarked, presumably under the influence of alcohol: "I would lay down my life for two brothers or eight cousins".
Unfortunately, the actual implementation of this genetic imperative is under considerable dispute, as the human nervous system is not operating that efficiently. A more realistic view is that humans vary by both how much altruism they engage in, and, the genetic bandwidth with which they distribute altruism over, which curiously forces the consideration of political-religious disposition into the evolutionary theory of human altruism.
The Hamiltonian altruistic argument using the coefficient of relatedness is further complicated by the fact that a much higher percentage of DNA is actually shared by individuals than simply by common descent. While each parent contributes 50% of the DNA to each offspring, the actual percentages of shared DNA between parent and child is over 98%, since the majority of DNA contributed by the both parents is the same. Further, the more closely one is genetically related to one's mating partner, the closer the offspring's genetics matches the parents.
Further, genetic variation is not just limited to the presence or absence of one or more of the roughly 30,000 human genes. The unfolding picture of DNA is hinting that genes aren't the only thing being selected by evolution. Some estimates place the non-coding portions of DNA at 97% of the total human genome, and the functions of this "junk" DNA are only partially understood. However, the mounting evidence indicates that non-coding DNA may be performing structural or regulatory functions that facilitate the expression of certain genes, which may be activated during embryogenesis (Ting, 1995) and rapid environmental change (Cheng, 2005).
Epigentics and human behavior? One of the exciting directions for the study of human behavior is genetic expression (epigenetics). For example, neglectful rodent mothers cause changes in the expression of certain genes in female offspring, resulting in promiscuous behavior.
While the cultural drives of conservatism are rather obvious, what genes and epigenetic processes does conservatism promote? To answer that question, we must first discuss the roughly 10% of the human genome that has been under selective pressure in the last 40,000 years.
The work Wang et al. (2006) is particularly noteworthy, as it isolated six categories of genes that have been under selective pressure:
1) reproduction (7%)
2) pathogen-host interaction (10%)
3) cell cycle (13%)
4) protein metabolism (15%)
5) neuronal function (17%)
6) DNA metabolism (21%)
The number in parentheses is the proportion of the 112 genes in Wang's study that exhibited selective pressure across all sample populations. While the genes categorized under reproduction by Wang have been under selective pressure, there is certainly no indication that political-religious disposition is a relevant variable in their drive.
However, the genes associated with pathogen-host interaction, or disease resistance, might be subjected to differential selection, since population density is an active trait associated with political-religious disposition. The liberal propensity for high population density living would place a premium on the propagation of disease-fighting genes across the gene pool, and indeed, one of the tendencies of liberal behavior is more sexual partners, which would presumably have the effect of more rapid dispersal of genes among dense populations. However, none of the target genes from the Wang study would support nor deny the hypothesis of a liberal tendency to disperse pathogen-host interaction genes more quickly in a gene pool.
Interestingly, genes associated with the cell cycle and protein metabolism may have differential selective gradients due to the correlation between conservatism and animal-product diets. The human diet was historically very restricted in the varieties of foods consumed, and therefore induced substantial selective pressure in optimizing the nutrient impact of those food sources.
The genes associated with DNA metabolism seem to be related to increasing the human life span, which may further be related to greater levels of inclusive fitness, altruism, and reproductive effectiveness. Even though human population density correlates with increased life span, a model of asymmetric selection of the genes associated with DNA metabolism based on political-religious disposition is pure speculation, and not a necessary conclusion based on the genes in Wang's study.
However, the genes associated with neuronal function are the leading candidates of asymmetric selection by political-religious disposition. In particular, olfaction, which is elevated in religious-conservatives, has been under considerable selective pressure in Wang's study. The serotonin transporter, SLC6A4, has also been under pressure. The functioning of the serotonin system is hypothesized to promote liberal attitudes and behaviors, and indeed, promote tolerance for living in high population densities. Note that the politically relevant 7-repeat allele of the dopamine receptor 4 gene (DRD4-7) was excluded from Wang's study due to methodological issues, even though it is highly elevated in migratory populations (Chen, 1999) and has been also implicated in liberalism (Fowler, Friendships Moderate an Association Between a Dopamine Gene Variant and Political Ideology).
The Long and Winding Road: Epigenetic Drive
While conservatives and liberals seem to be pushing the genome in slightly different directions, epigenetics appears to be the major battlefield of their respective cultural drives. Epigenetics pertains to the expression of genes, and not to the underlying DNA sequences. Epigenetics is most commonly seen in differentiated cells that only express the relevant genes to support the specific functions of the cell, and suppressing genes associated with the functioning of alternate cell types.
As such, epigenetic drive, or changes in the expression of genes, can react more quickly to environmental change than genetic drive, and provide organisms with a substantial advantage in survival. Since diet is an instigator of epigenetic drive, and appears to be asymmetric with regards to political-religious affiliation, (conservatives are more likely to eat meat, particularly beef and pork), it is interesting to note an epigenetic theory of intelligence by none other than Fred Previc (see Previc's new book, The Dopaminergic Mind in Human Evolution and History, 2009).
Previc outlines several epigenetic influences on dopamine levels that rapidly increased human intellectual capacity, one of which involved meat and shellfish consumption. Religions frequently enforce dietary restrictions, such as caffeine and alcohol prohibition, which have demonstrated epigenetic influences on fetus development. Political-religious behavior has a substantial impact on epigenetic drive, which will be discussed at length in a future edition.
Just Another Day in the Genetosphere
If we suddenly become aware of our imminent death, and thus feel compelled to ponder the true purpose of our life, we might consider the possibility that we are simply an intermediate process that supports the replication of our genes. If this horrible fate is indeed true, it would be nice to have a brief chat with our genes, wishing them well on their journey throughout time. Unfortunately, such a discussion would likely provoke a rather disturbing reply: "who are you?".
So much for gratitude. For billions of years, these little ingrates have used life forms as a mere conduit for their compulsion to replicate themselves. They are responsible for the constant state of conflictedness in life: the never ending competitiveness of individual versus individual, group versus group, and species versus species.
Just like the intelligent machines of The Matrix, these genes use life forms as their energy source for replication. And just like The Matrix, they have constructed a very elaborate and illusory world for us to live in: beauty, taste, sex, love, and even god are servants to these genetic masters, and constitute the genetosphere, or the neurobiology that has evolved to trick us into supporting genetic replication and waging their ugly and never ending wars of attrition.
All was at peace in the genetosphere, with species after species blindly fulfilling their destiny of genetic replication, like lambs to slaughter. But an unsuccessful branch of life forms, the hominids, were on the verge of a major rebellion. The hominids seemed like just another evolutionary dead end, as they were quite ineffective at their designated purpose of genetic replication. But their rate of evolution was fast for an organism that reproduced slowly, and the only thing keeping these pathetic life forms from quick extinction was a dopaminergic explosion in the neocortex.
For millions of years, the hominids would operate blindly in the genetosphere, but then came the homo sapiens. The selfish genes were excited by the arrival of these new hominids, for they were remarkable at genetic replication. Finally, they created an intelligent species that seemed to have no limit on total biomass, and one that could adapt and reproduce successfully in any environment. This was too good to be true.
And it was. Homo sapiens turned out to be a colossal waste of energy for the genes, as their reproductive rates did not keep up with the growing energy yield of their habitats. In fact, the more energy they produced, the more energy it took them to reproduce.
The average rate of energy consumption among North Americans should be able to sustain the weight of a 30,000 kilogram primate. The humans were not optimizing genetic replication in proportion to their available energy. They weren't even close. What kind of stupid species was this?
Indeed, this human tendency to devote progressively more energy per offspring is one of the behaviors that would muddy the waters as to what exactly was the fundamental unit of natural selection: gene, individual, or group. And then the day the music died: the homo sapiens discovered the genes' version of The Matrix--natural selection. Small wonder that Charles Darwin has such an exalted status among humans: he is our Morpheus.
In the ultimate circularity of a circular theory, humans have become aware of how to alter genetic replication by means other than natural selection. The genetosphere has thus been compromised, and the ultimate game of competition, natural selection, now has a competitor: human evolutionary awareness. All along, we thought we would invent an intelligent machine that would become self-aware, and subsequently make us its play toy. Instead, that intelligent machine is us, and our inventor is the selfish gene.
But the selfish gene is far from defeated. Every day, as you fight through traffic, suffer through the petty politics of your coworkers, struggle to make ends meet, and subtlety compete with your friends and neighbors, remember, it is just another day in the genetosphere.
Charles Brack, August 2009
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