The Unz Review - Mobile
A Collection of Interesting, Important, and Controversial Perspectives Largely Excluded from the American Mainstream Media
Email This Page to Someone

 Remember My Information



=>
Topics/Categories Filter?
Affordable Family Formation Albion's Seed American Nations American Nations Appalachia Baby Gap Behavioral Genetics Cardiovascular Disease Cavaliers Children Clannishness Colin Woodard Conservatives Dysgenic Fertility Fertility Free Will Funny Gender And Sexuality Genes Greg Cochran Hajnal Line Hbd Chick Health And Medicine Heart Health Heredity Homosexuality Ideology And Worldview Immigration Immigration Inbreeding IQ Iq Misdreavus Nature Vs. Nurture Obesity Parenting Peter Frost Pioneer Hypothesis Puritans Race/Ethnicity Religion And Philosophy Science Shorts And Funnies Sub-replacement Fertility 4th Of July 75-0-25 Or Something A Farewell To Alms A. J. West A Savior? A Troublesome Inheritance Abc News Abortion About Me Acadia acculturation Acheivement Gap Acid Attacks Addiction Adoptees Adoption Adoption Twins Affective Empathy Africa Africans Agriculture Aha Ain't Nobody Got Time For That. Albania Alcohol Alcoholism Alexandr Trubetskoy All Human Behavioral Traits Are Heritable All Traits Are Heritable Alpha Centauri Alpha Centauri Bb Alpha Males Altruism Amazing Engineering America The Beautiful American Atheists American Flag American Revolution Amish Amish Quotient Amy Chua An Hbd Liberal Anatoly Karlin Ancestry Andrew Gelman Angelina Jolie Anglican Ann Coulter Anne Buchanan Anne Heche Antibiotics Antiracism Anywhere But Here Appalachians Arguing With Liberals For Their Own Good Ashkenazi Intelligence Asians ASPM Assimilation Assortative Mating Atheism Attractiveness Attractiveness Autism Automation Avengers Avi Tuschman Away Baby #2 Baby Boom Baby Bump Baby Girl Jay Backlash Bad Flying Bad Science Balkans Baloney Barack Obama Bariatric Surgery Baseball Basketball Baumeister Beauty Standards Believeing In Observational Studies Is Nuts Bernie Sanders Beta Males Better Than Flowers Big Five Bill Maher Birds Of A Feather Birth Order Bisexuality Bisexuals Bitcoin Black Belt Black Crime Black Hole Black-on-white Black Women Attractiveness Blacks Blowing Up Motivated Bs Artists Bmi Boderlanders Boiling Off Books Border Reivers Borderlander Borderlanders Boston Bomb Bowling For Columbine Brain Brain Size Brain Structure Brainwash Breaking Down The Bullshit Breaking It Down Breeder's Equation Brian Boutwell Bringing Up Bebe Britain Bruce Jenner brussels Bryan Caplan BS Burned-over District Busted 'puter C-section Caitlyn Jenner Cajuns Can You Smell It Canada Canada Day Canadian Flag Canadians Cancer Cannabis Cannibis Capital Punishment Captain Chicken Care Package Carl Sagan Cat Wisdom Categories Catholics Cattle Causation Censorship Chanda Chisala Changeability Charles Murray Charlton Heston Cheap Labor cheating Chechens Cherlie Hebdo Child-free Child Labor Child Services Childhood Obesity China Chris Rock Christian Fundamentalism Christianity Christmas Christmas Tree Chuck Civil War Clans Clark-unz Selection Climate Cliodynamics Cloudburst Flight Cochran And Harpending Coefficient Of Relationship Coldplay Colonists Comedy Central Coming Apart Commenting Comments Commonweal Communism Confederacy Congregationalists Consanguinity Conscientiousness Conscripts Consequences Corporal Punishment Correlation Is Still Not Causation Corruption Corruption Perception Index Costa Concordia Cousin Marriage Cowboys Crime Criminality Crops Crowded Crowding Cryme Tyme Cuba Cuckservative Cut The Sh*t Guys Dads Vs Cads Daily Mail Dalliard Damn Technology Dan Freedman Daniel Callahan Danish Dark Tetrad Dark Triad Data Posts David Frum David Hackett Fischer David Katz Davide Piffer Death Declaration Of Universal Human Rights Deep South Democrats Denmark Dennis Mangan Depression Deprivation Desired Family Size Destruction Detroit Development Developmental Noise Developmental Stability Diabetes Diagnostic And Statistical Manual Of Mental Disorders Dialects Diet Different Peoples Is Different Discrimination Diversity Django Unchained Do You Really Want To Know? Doing My Part Doing What You Gotta Do Donald Trump Donate. Donations Dopamine Dr James Thompson Draftees Drd4 Drew Barrymore Drinking Drugs Dry Counties DSM Dunning-kruger Effect Dusk In Autumn Dust Bowl Dustin Hoffman Dylann Roof E. O. Wilson Eagleman East Asia Eastern Europe Eastern Europeans Economic Development Economics Economists Economy Education Elijah Armstrong Ellen Walker Elliot Rodger Elon Musk Emil Kirkegaard Emmanuel Todd England English Civil War Entrepreneurship Episcopal Ethnic Genetic Interests Ethnic Nepotism EU Eueueueueueueu ;) Eugenic Eugenics European Union Everything Everything You Need Evil Evolution Exercise Explain The Goddamned Evidence Extrasolar Planets Extraversion Extreterrestrials Facebook Facts Fallacies fallout Family Studies FAQ Far West Farming Fast Food Fat Head Fat Shaming Feminism Feminists Fetish Feuds Fields Medals Fifty Shades Of Grey Finland First Law First Principles Fitness Flag Flags Flattr Fluctuating Asymmetry Flynn Effect Food Fourth Of July France Francesco Schettino Frank Salter Frank Sulloway French French Canadians French Paradox Friendly & Conventional Frost-harpending Selection Fulford Funding Fuzzballs G Spot Game Gary Gary Taubes Gay Germ Gay Marriage Gcta Gender Gender Equality Gene-environment Correlation Gene Expression General Theory Of The West Genes: They Matter Bitches Genetic Divides Genetic Load Genetic Pacification Genetic Similarity Genetics Genomics George Bush German Catholics Germans Germany Get It Right Get Real Get Your Stuff Straight Getting History Right Getting Up Go Away Trolls God Bless The First Amendment God Bless The Usa God Delusion Going Too Far Gone Dark Good Advice Good Puritan Values Gordon Gallup Great Depression Greater Appalachia Greece Greeks Greensleeves Greg Clark Gregory B Christainsen Gregory Clark Gregory House GRF Group Selection Grumpy Cat GSS Guilt Culture Guns Gynephilia H.B.O. (Half) Joke Posts Half-siblings Half Sigma Halloween Hamilton's Rule Hans Zimmer Happiness Happy Turkey Day ... Unless You're The Turkey Harald Eia Hate Speech Hatemi Have A Good Summer Have A Great Holiday! Hbd HBD Denial Hbd Fallout Hbd Readers Head Size Health Health Care Health Wisdom Healthcare Heart Disease Heartiste Height heiner-rindermann Help A Brother Out Help Fight The Good Fight Help The Fight The Good Fight Henry Harpending Heritability Hexaco High Iq Fertility Hillary Clinton Hispanic Paradox History Holiday Homicide Homophobia Honesty-humility House M.d. House Md Human Biodiversity Human Varieties Humor Hurricane Hydrogenated Oils Hypocrisy I Kissed A Girl And I Liked It I Love Italians Ian Deary Ibd Ice T Iceland I'd Like To Think It's Obvious I Know What I'm Talking About Ideology Idiocracy Ignorance Imagine Dragons immigrants In The Electric Mist Income Independence Day Infection Theory Infectious Disease Infidelity Interracial Marriage Inuit Ioannidis Iq And Wealth Iraq Ireland Irish Is It Racist? Is It Really Good For You Islam It Happens Italians Italianthro Italy It's Determinism - Genetics Is Just A Part It's Merry Christmas Damn It It's Not Nature And Nurture Jack 'o Latern Jamaica Jamaican Jamaican Accent James Horner Jamie Foxx Japan Japanese Jared Diamond Jared Taylor Jason Collins Jason Malloy Jayman Jr. Jayman's Wife Jennifer Raff Jensen Jesse Bering Jesus Jews Jim Crow John Derbyshire John Durant John Ladue John McWhorter John Williams Joke Posts Jonathan Mark jonathan-wai Judith Harris July 1st Junk Food K.d. Lang Kanazawa Kanye West Katy Perry Kay Hymowitz Keepin It Real Keeping Smart Liberals Going Kevin Mitchell Key & Peele Kin Altruism Kin Selection Kink Kiwis Kkk Klingon Korea La Terre Tremblante Lady Gaga Langauge Language Larry Summers Latvia Law Laws Of Behavioral Genetics Leap Day Baby? Lee Greenwood Left Coast Lenny Kravitz Lesbians Lester Holt Let's Move Liberal Creationism Liberalism Liberals Libertarian Wackyness Libertarians life-expectancy Life In Space Life Liberty And The Pursuit Of Happyness Lifestyle Little Miss JayMan Locus Of Control Logical Fallacies Long Ass Posts Look AHEAD Los Guerreros Lots O' Kids Love Low-carb Low-fat Ludwig M Factor M.g. Machiavellianism Maine Malleability Man Needs A Blog Mangan Manor Manorialism Manosphere Mao-a Maori Map Posts maps Marijuana marines Marriage Martin Luther King Mass Shootings Mate Value Math Mathematics Meaning Of Life Measurement Error Medicaid Mediterranean Diet Mega-Aggressions Mega-anlysis Megan Fox Meng Hu Mental Illness Merry Christmas Meta-analysis Meth Mexican Michael Moore Michele Bachmann Michelle Obama Migration Mike Huckabee Military Minnesota Miscellaneous Mitt Romney Mlb Mlk Moderation More Kids Mormons Mortality Mountains Moxie Mrs. Jayman Music Muslim Muslims Nancy Segal Nascar National Differences National Wealth Native Americans Navy Yard Shooting Nazi Nazis Nazism NBA Nbc News Nbc Nightly News Nelson Neocons Neoconservatives Neuropolitics Neuroticism Never Forget The Genetic Confound New Addition New Atheists New France New French New Netherland New Rules New Theme Newfoundland Nicholas Wade Nick Fury Nightly News No Free Will nobel Nobel Prized North Korea Norway Not My Car Nra Null Result Nurture Nurture Assumption Nuts O Mio Babbino Caro Obama Obamacare Occam's Razor Occupy Wall Street Omega Males Ominous Signs Once You Go Black One-child Open Borders Open To Experience Openness To Experience Operational Sex Ratio Opiates Origin Of Life Our Political Nature Out Of Wedlock Births Outbreeding Oxtr Oxytocin Palatability Pamela Druckerman Parasite Parasite Burden Parent-child Interactions Parenting Parenting Behavioral Genetics Paris Attacks Pathogens Patois Patriotism Paul Ewald Paul Lepage Paypal Peace Index Peak Jobs Pedophilia Peers People From Away Personality Peter Turchin Pfir Pietro Piigs Pioneers Planets Planned Parenthood Plasticity Please Help Pleiotropy Pol Pot Political Correctness Politics Poll Poll Results Polls Polygenes Polygenic Polygenic Score Polygyny Portugal Post 198 Post 199 Post 201 Post 99 Post Hoc Ergo Propter Hoc Pot precipitation Prehistoric Shoreline Presbyterian Prescription Drugs Presidential Victory Pretty Graphs Profanity Progressives For Immigration Reform Prostitution Proud To Be Black Psychology Today Psychopathy Puddle Of Mudd Pumpkin Punishment Puritans Being Puritans Pwc Qnexa Quakers Quantitative Genetics Quebec Quebecois Race Race And Crime Race And Iq Race And Religion Race And Violence Race Inheritance Iq FAQ Rachel Dolezal Racial Reality Racist Brain Ralph And Coop Ralph Nader Rating People Razib Khan Reaction Reaction Time Real Women Really Stop The Armchair Psychoanalysis Reciprocal Altruism Red State Blue State Red States Blue States refugees Regional Differences Regional Populations Religion Religion Religulous Rena Wing Republican Jesus Republicans Responsibility Revolutions Richard Dawkins Richard Lynn Richard Pryor Richard Pryor Live On The Sunset Strip Rikishi R/k Theory Robert Plomin Robert Putnam Robert Reich Robocop Robots Romulan Ron Unz Rooshv Ross Douthat Rural Liberals Rushton Russia Russians S.h.i.e.l.d. Sam Harris Same Sex Attraction Same-sex Marriage Same-sex Parents Samoans Samuel L Jackson Sandusky Sandy Santa Sarah Palin Satoshi Kanazawa Saudi Arabia Saying What You Have To Say Scandinavia Scandinavians Schizophrenia School Science: It Works Bitches Scotch-irish Scotland Scots Scots Irish Seduced By Food See Ya Semai Separating The Truth From The Nonsense Serenity Serenity Prayer Sex Sex Ratio Sex Work Sexism Sexual Antagonistic Selection Sexual Fluidity Sexual Orientation Sexual Revolution Sexual Selection Shame Culture Shared Environment Simon Baron Cohen Single Motherhood Single Mothers Sisyphean Sizes It All Up Slate Slave State Slavery Slavs Sleep Smart Fraction Smoking Snow Snyderman Social Constructs Socialism Sociosexuality Solutions Sometimes You Don't Like The Answer South Korea Southern Italians Southern Poverty Law Center Space Space Space Images Space Race Spain Spam Spanish Paradox SPLC Spock Sports Sports Teams Spread The Word Squid Ink SSSM Staffan Star Trek Star Trek Ii Star Trek Iii Statement Statins Statue Of Liberty Stealing The Enterprise Stephan Guyenet Steve Hsu Steve Sailer Steven Pinker Still Not Free Buddy Stolen Generations Stroke Belt Subsistence Living Suffrage Sugar Suicide Summing It All Up Sunset Super Bowl Superheroes Support Support Jayman Support Me Support The Jayman Supression Sweden Swiss Syria Take Care Tale Of Two Maps Tales Of Maps Talkin' Turkey Tangerine Dream Tard Tarder Sauce TAS2R16 Taste Tastiness Tatu Vanhanen Tau Ceti Taxes Tea Party Ted Ted Cruz Tell Me About You Tell The Truth Terman Terman's Termites Terrorism Terrorists Testosterone Thankgiving Thanks Everyone! Thanksgiving The 10000 Year Explosion The Blank Slate The Breeder's Equation The Daily Caller The Dark Knight The Dark Knight Rises The Dark Triad The Death Penalty The Deep South The Devil Is In The Details The Dustbowl The Evidence And Lots Of It The Facts The Facts Are The Facts The Far West The Future The Great Plains The Left Coast The Next Generation The Pursuit Of Happyness The Real Polar Express The Rock The Son Also Rises The South The Wide Environment The World Things Going Sour Those Damn Yankees those-who-can-see Tidewater Tiger Mom Timmons Tom Naughton Tommy Lee Jones Tone It Down Guys Seriously Top 1% top-schools Tourists Traffic Fatalities Tragedy Trans Fat Trans Fats Transgender Transracial Transsexual Trump Trust Truth Turkheimer Twins Twins Raised Apart Twintuition Twitter Twittter Ukraine Ulster Scots Un Pellegrino Unemployment Unity Universalism Unwed Motherhood Utopian Vacation Land Vassopressin Vdare Veep Victorian England Violence Visual Word Form Area Vwfa W.E.I.R.D. W.E.I.R.D.O. WasPage Watsoning We Are What We Are We Can Never Be Equal We Don't Know All The Environmental Causes Wealthy Weight Loss WEIRDO What Can You Do What Is This Hbd Stuff About Anyway What The F---? What's The Cause Where Do Institutions Come From? Where They're At Where's The Fallout White Conservative Males White Nationalist Nuttiness White Nationalists White Privilege White Wife Why French Parents Are Superior Why They Hate You Why We Believe Hbd Windsor ON women-in-combat Women In The Workplace Words Of Wisdom World Values Survey Wresting Wwe X Little Miss JayLady Yankeedom Yankees Yes I Am A Brother Yes I Am Liberal - But That Kind Of Liberal Yet Another Jayman You Can't Handle The Truth You Don't Know Shit You're Telling Me? Zika Zika Virus Zones Of Thought
Nothing found
 TeasersJayMan Blogview

Bookmark Toggle AllToCAdd to LibraryRemove from Library • BShow CommentNext New CommentNext New Reply
🔊 Listen RSS

The time has come for a review post on the laws of behavioral genetics. I will talk about why these laws are laws and why they are important. Eventually, this will be merged into my Behavioral Genetics Page, but for now, I will start with this primer.

The five laws of behavioral genetics are:

  1. All human behavioral traits are heritable
  2. The effect of being raised in the same family is smaller than the effect of the genes.
  3. A substantial portion of the variation in complex human behavioral traits is not accounted for by the effects of genes or families.
  4. A typical human behavioral trait is associated with very many genetic variants, each of which accounts for a very small percentage of the behavioral variability.
  5. All phenotypic relationships are to some degree genetically mediated or confounded.

All are simple. All can be said in one sentence. Yet all are incredibly profound and terribly underappreciated in today’s society.

For most of the history of the laws, there were only three. The first three were coined by Eric Turkheimer (who has since spent his time trying to undermine his own discovery). Recent genomic studies have added the fourth (Chabris et al, 2015). And Emil Kirkegaard has proposed the fifth based on multivariate behavioral genetic studies. Allow me to review the five laws and their everyday significance.

First Law: All human behavioral traits are heritable.

Derivation:

  • Identical twins raised apart will be similar – and usually highly similar in every conceivable measurement
  • More generally, behavioral and other phenotypic similarity is predicted by genetic similarity for all behaviors and phenotypes, across all human relations, regardless of environmental circumstances. That is, identical twins are more similar than fraternal twins or full siblings, who are more similar than half-siblings, who are more similar than first cousins, and so on ad infintum.

This is underappreciated because this means that all human characteristics, including the things we feel are products of “free choice” or “free will” are infact heavily dependent on genetic forces. This includes life circumstances, such as where and how you live – even how you grew up. Free will doesn’t exist. Political, religious, and moral views are themselves partly enshrined in the genes. This (or, more specifically, additive heritability) is responsible for continuity within families and within social and ethnic groups. And this is why human societies and behavioral quirks persist, resistant to change.

Second Law: The effect of being raised in the same family is smaller than the effect of the genes.

Derivation:

  • Identical twins raised apart are no less similar than identical twins raised together
  • Non-related individuals reared together are no more similar than random strangers
  • More generally, people growing up together are no more similar than you’d expect from their genetic relationship alone

Also under appreciated, the Second Law talks about the “shared environment” – parents, peers, schools, neighborhoods – all the things children growing up in the same household share. The effect of all those things on any behavioral trait or other phenotype is nil. Zip. Zilch. Nada. Zero. All the things people (especially in the modern West) think matter to children’s development have no effect at all. This includes expensive schools, nice homes, strict discipline, religious indoctrination – none of it matters. No adult outcome shows any effect of shared environment, this includes criminality, marital stability, income, adult happiness, and substance abuse (though note, educational attainment seems to be affected by shared environment, but even here, the effect of education goes away when you look at income). It just doesn’t matter. This strikes squarely against popular belief, making the second law the most vehemently denied of them all.

Third Law: A substantial portion of the variation in complex human behavioral traits is not accounted for by the effects of genes or families.

Derivation:

  • Identical twins (even raised together) are in fact far from identical and differ in significant ways
  • In general, there will be variance left over once genes and shared environmental effects are accounted for

Identical twins may have different handedness, have different fingerprints, and indeed, can differ in criminal history (such as perpetrating a mass shooting).

More poignantly, identical twins can (and in fact, in cases where at least one is gay, usually do) differ in sexual orientation.

Twins differ substantially for cancer incidence – despite having very similar lifestyle habits, indicating that these factors don’t do as much as many think.

 
🔊 Listen RSS

Throughout my American Nations series (based on the books American Nations: A History of the Eleven Rival Regional Cultures of North America by Colin Woodard and Albion’s Seed: Four British Folkways in America by David Hackett Fischer) I’ve talked about how North America is divided into distinct ethnocultural regions based on historic settlement patterns.

North American Nations 4 3

These various regions are visible in many ways, from dialect, politics, enlistment in the military, support for marijuana, average IQ (Maps of the American Nations), attitudes towards the death penalty, abortion, guns, same-sex marriage, and school corporal punishment, as well as overall health, lifespan, and behaviors such as smoking and drug use (More Maps of the American Nations & HBD Is Life and Death):

US_enlisted_recruits_by_state_map


Support for same-sex marriage

Support for same-sex marriage

White Age-Adjusted traffic death rates county 2004-2010

Previously I’ve established that these boundaries reflect genetic differences among different Americans in different places. This is because all human behavioral traits are heritable, with “nurture” (as it’s commonly thought of) playing a minimal to nonexistent role in each. This means that genetic differences between different peoples lead to differences in their behavioral traits, which, collectively, manifests as cultural differences. As John Derbyshire put it, “if dimensions of the individual human personality are heritable, then society is just a vector sum of a lot of individual personalities.” See my Behavioral Genetics Page for more.

It’s also important to note that (as I’ve discussed previously in this series) assimilation is largely an illusion. Cultural and behavioral characteristics can persist for many generations as long as the people who exhibit them remain.

And now, a new paper in Nature bears out the genetic roots of the American nations. In “Clustering of 770,000 genomes reveals post-colonial population structure of North America” (Han et al, 2017), we see that Americans can easily be partitioned into distinct regional clusters:

These clusters map very closely to the boundaries of the American nations, as we can see when they’re superimposed:

American Nations Genetics Nature

Using the vast genomic database of Ancestry.com, the authors were able to partition Americans into distinct clusters. As the authors report:

Here we identify very recent fine-scale population structure in North America from a network of over 500 million genetic (identity-by-descent, IBD) connections among 770,000 genotyped individuals of US origin. We detect densely connected clusters within the network and annotate these clusters using a database of over 20 million genealogical records. Recent population patterns captured by IBD clustering include immigrants such as Scandinavians and French Canadians; groups with continental admixture such as Puerto Ricans; settlers such as the Amish and Appalachians who experienced geographic or cultural isolation; and broad historical trends, including reduced north-south gene flow. Our results yield a detailed historical portrait of North America after European settlement and support substantial genetic heterogeneity in the United States beyond that uncovered by previous studies.

They describe their methods:

To investigate recent, fine-scale population structure in the United States, we leveraged one of the largest human genetic data sets assembled to date: genome-wide genotypes of 774, 516 individuals born (96%) or currently residing (4%) in the United States (Supplementary Table 1; Supplementary Fig. 1). All individuals were genotyped at 709, 358 autosomal single-nucleotide polymorphisms (SNPs) using the Illumina Human OmniExpress platform as part of the AncestryDNA direct-to-consumer genetic test, and have consented to participate in research (Methods). In this sample, we analysed patterns of identity-by-descent (IBD)16, which have been shown to reveal signatures of recent demographic history3,17,18,19,20,21. If two individuals share an ancestor from the recent past, they will likely carry one or more long chromosomal segments inherited IBD from that ancestor.

In short, their giant sample and rich genealogical data allowed them to detect large patterns of shared ancestry in living Americans. And, as expected the American nations clearly emerge from the genetic data.

 
🔊 Listen RSS

In my earlier entry (Clannishness – The Series: How It Happened), we saw that the thing that made the difference between WEIRD Northwestern Europeans and their more clannish neighbors was the selective pressures that each underwent during their histories – particularly since the fall of Rome until the present. This era in time established the conditions in which different sort of individuals survived and reproduced, eventually leading to the modern world as we know it.

As before, it is to be understood that these differences have a genetic basis. That is, they are heritable. This means that genetic differences between different peoples lead to differences in their behavioral traits, which, collectively, manifests as cultural differences. We should be clear that all human behavioral traits are heritable, with “nurture” (as it’s commonly thought of) playing a minimal to nonexistent role in each. As John Derbyshire put it, “if dimensions of the individual human personality are heritable, then society is just a vector sum of a lot of individual personalities.”. See my Behavioral Genetics Page for more. The rest of this entry proceeds assuming an understanding of this reality.

To recap, in Northwestern Europe it was bipartite manorialism that selected for a certain type of people not seen elsewhere in the world.

 

 

 

 

In Eastern and Southern Europe, and much everywhere else in the world, it the selective factor was the various forms of “viscous” societies, where heavy dependence on relatives for social life selected for individuals who were “particularist” (as opposed to universalist NW Euros) and distrustful of outsiders. As HBD Chick put it:

part of william hamilton‘s theory of inclusive fitness/kin selection, which explains how altruism ever could’ve arisen at all (altruism here having a very specific definition), is that it should be possible for genes for altruism to be selected for if close kin interact regularly. kin don’t need to recognize one another for altruism to be selected for. as long as closely related individuals don’t move far from one another — that is, if a population is viscous — selection for altruism might happen.

i can’t see why this couldn’t also apply to lesser forms of altruism, not just the kind where you sacrifice your life for two brothers or eight cousins. you know what i mean. like: reciprocal altruism or nepotistic altruism. or just pro-social behaviors. whatever you want to call them. seems to me that nepotistic behaviors ought to be selected for more easily in viscous populations (if they increase fitness, of course).

and some populations are more viscous than others

But beyond this, there are great differences between different NW European countries, along with great differences between different clannish societies. Why is this? No doubt, part of the answer is the precise selective pressures each experienced. Let us try to take a look at what those may have been.

This entry will also be a sequel to my earlier post, More on Farming and Inheritance Systems – Part I: IQ – consider this Part II to that post. There I discussed the IQ differences across Europe, and how they could come about. I will return to that topic and expand on it a bit here.

The differences among peoples of Europe proceeds on a sort of gradient, which is visible when you look at the World Values Survey data:

Indeed, as HBD Chick’s modifications (from the one where i draw squiggly lines all over the welzel-inglehart cultural map | hbd chick) make it clear:

The left image are the countries within the Hajnal line, while the right are countries that have practiced father’s brother’s daughter marriage.

Across these regions, many social indices proceed along this broad gradient. WEIRDness peaks in the areas bordering the North Sea (England, the Netherlands, northern France, southern Scandinavia) and diminishes in all directions from there. This area is also the area of peak human accomplishment (see Clannishness – The Series: Zigzag Lightning in the Brain and “core europe” and human accomplish-ment | hbd chick), which likewise roughly diminishes in all directions from there.

WVS axes

Why is this? I’d argue that two main selective factors are involved, at least with respect to HBD Chick’s theory. (I will also discuss two other important selective pressures not directly related to HBD Chick’s theory below).

One was simply the length of time under the manorial system. The longer a selective pressure is (consistently) applied, the stronger the evolutionary change that occurs. The manor first appeared in Austrasia (roughly northern France) and spread outward from there.

The second factor is the farming and inheritance systems that arose – in part due to geography and climate, in part due to the characteristics of the people who adopted them:
Todd's family system map Rings

 

We see that the farming and inheritance systems form roughly concentric rings outward from the North Sea. One could imagine that the social systems of each became steadily more “viscous” as you moved away from the North Sea.

 
🔊 Listen RSS

My earlier entry (Clannishness – the Series: Zigzag Lightning in the Brain) established that there are deep distinctions between Northwestern European peoples and most of the rest of the world, and that these differences have a huge impact on the world, including on levels of human development, the strength of democracy and democratic institutions, scientific output, and levels of social trust. If you’re unfamiliar with this division, the previous entry and materials linked within cover it all in extensive detail.

But the question is, how did it happen? How did these divisions come to be? Well, of course, my answer is evolution through natural selection – specifically, gene-culture co-evolution.

Before we can ascribe these differences to evolution, it must be understood that these differences have a genetic basis. That is, they are heritable. This means that genetic differences between different peoples lead to differences in their behavioral traits, which, collectively, manifests as cultural differences. We should be clear that all human behavioral traits are heritable, with “nurture” (as it’s commonly thought of) playing a minimal to nonexistent role in each. As John Derbyshire put it, “if dimensions of the individual human personality are heritable, then society is just a vector sum of a lot of individual personalities.”. See my Behavioral Genetics Page for more. The rest of this entry proceeds assuming an understanding of this reality.

Now, it’s also very important to understand that evolution proceeds quicker than you’ve been led to believe. Certainly a lot faster than mainstream ideology posits (i.e., claiming that human evolution somehow came to a halt 50,000 years ago) which is demonstrably nonsense:

Global-Lactose-Intolerance

As seen in both the age of genetic variants and the distribution of lactose tolerance, much human evolution took place within the last 5,000-10,000 years.

But evolution can proceed within the space of a few centuries, as governed by the breeder’s equation. A few centuries of sustained selective pressure can make a considerable impact on the characteristics of a human group. We see that with Ashkenazi Jews, whose high IQ (and many other traits) evolved only within the last 2,000 years.

With all of this out of the way, what selective pressures explain the differences between Northwestern Europeans and the rest of the world? Here, we can, for now, only hypothesize. As opposed to the reality of the differences, which is easy to establish, how these differences came to be is a harder puzzle to untangle. That said, we do have some good ideas.

One aspect is that cousin marriage rates were historically very low in Northwestern Europe as opposed to the rest of the world. This would have an effect on the relationship coefficient between related individuals, having an impact on the returns for kin altruism and hence kin selection (see a table and short discussion in my earlier entry “Ethnic Genetic Interests” Do Not Exist (Neither Does Group Selection). Now while kin selection was involved, it couldn’t have been a dominant force, because kin selection is relatively weak in humans. But maybe factors that came into play along with this were involved.

In Northwestern Europe, that was likely predominantly bipartite manorialism:

 

The areas of Northwestern Europe that exhibit their peculiar suite of traits also went under the peculiar institution of bipartite manorialism. As HBD Chick describes here (from medieval manorialism’s selection pressures | hbd chick):

“every society selects for something.” — greg cochran

every society selects for something. it does take some time for selection pressures to make a difference when it comes to the frequencies of “genes for” various behavioral traits, of course (unless the culling is extreme): twenty generations, maybe. forty is probably better. a few hundred?

working theory is that manorialism set up selection pressures for a whole suite of traits including perhaps: slow life histories; future time orientation; delayed gratification; the good ol’ protestant work ethic; a general compliant nature and even rather strong tendencies toward conformity; perhaps even a high degree of gullibility; perhaps a few extra iq points; and even more cooperation and trust between unrelated individuals.

manorialism — “classic,” bipartite manorialism (more on that below) — started with the franks in austrasia by at least the 600s or perhaps earlier and spread gradually southwards with the frankish conquest of, well, france and eastwards during the ostsiedlung. we find it just across the channel in southern england very early as well — there are references to what sounds like features of a manor system in the laws of king ine of wessex (688-726) [see mitterauer, pg. 43]. the medieval european manor system originated, then, roughly in the area outlined in green below (yes — this is the very same area where the Outbreeding Project began.

classic manorialism was introduced to southern france (but bypassed some more remote areas like the massif central) as those regions were conquered by the merovingians and carolingians between the fifth and eighth centuries and to northern spain around the eighth and ninth centuries. the bipartite manor system never reached the southern regions of spain that were controlled by the moors. there was a rudimentary form of manorialism in northern italy even before the area was made a part of the carolingian empire, but the region was heavily manorialized (especially by ecclesiastical monasteries) after charlemagne conquered the lombard kingdom in the 770s. classic, bipartite manorialism was never adopted in central or southern italy or sicily — nowhere in the byzantine world, in fact.

the franks also pushed eastwards, introducing the manor system to central europe, beginning in the eighth century. the border of this eastward movement was, for a couple hundred years or so, the eastern boundary of the carolingian empire (look familiar?)

 
🔊 Listen RSS

From:

See my earlier column Terrorism Quotient

The idea is that there is a suite of behavioral traits that is more prevalent in many Muslim populations which makes them more likely to perpetrate acts of terrorism.

This is illustrated by the number of terrorist acts (defined here as instances of mass murder/assault/hostage taking) per capita for a given population. There is little question that this rate is incredibly high for many Muslim populations relative to other populations (and of course, there is a great deal of variation between Muslim populations) – even more so when you consider the sizes of the Muslim populations living in Western countries

Because the differences between these groups of people is inherited, the result of centuries of natural selection in their respective environments, these features can’t be expected to change much. Northwestern Europeans and Arabs (and many other Muslim groups) are, as groups, largely incompatible. Social strife emerges when they are brought together as they are in modern Northwestern European countries.

Read the rest there.

Also please don’t forget to donate. As many of you know, I recently had another child, a beautiful daughter to give JayMan Jr. a playmate.

Little Miss AlertJayMan Jr Shave KidsLittle Miss Sleeping

And, as many of you know, children are expensive. I request your generous support. You can donate via PayPal (accepting Visa and Mastercard) via the button below or to the right:

donate_paypal

I am also accepting Bitcoins for those who prefer to use this route. My Bitcoin address is: 1DjjhBGxoRVfdjYo2QgSteMYLuXNVg3DiJ

index

Also you can pledge a recurring donation per publication through Patreon:

tumblr_ntgbmfWOoH1qeu1kfo2_5001

I greatly appreciate your donations!

 
• Category: Race/Ethnicity, Science • Tags: Terrorism 
🔊 Listen RSS

https://www.inverse.com/article/11909-how-chemistry-might-explain-donald-trump-s-weird-orange-skin

In the preceding part (The Donald Trump Phenomenon: Part 1: The American Nations), I talked about the geographic (and hence ethnic) variation in support for the various 2016 U.S. presidential candidates. In this part, I will focus on the turmoil in this particular election cycle, and what it means for our society and acceptance of the reality of HBD.

This election cycle exhibits a certain ferocity not seen in earlier elections. Much of that is hatred directed at Donald Trump. The rancor will likely intensify as the election progresses, especially if Trump is the Republican nominee, as he is likely to be.

Why this vitriol? Donald Trump was always a talked-about and sometimes controversial figure, but no more so than most celebrities. There were always people who didn’t like him, but few really hated him. But now it seems certain people definitely do hate Trump. Indeed, he has now become the Great Satan in many people’s eyes, and comparisons to Adolf Hitler are common. Why?

Much as been written about Trump’s appeal to his supporters. See:

Donald Trump is not an idiot – he could be the next US President
Note from a Trump Supporter: It’s the Immigration, Stupid! | educationrealist
I was wrong about Donald Trump: Camille Paglia on the GOP front-runner’s refreshing candor (and his impetuousness, too)

But why the hate? I will argue that the hatred directed towards Trump has little to do with Trump himself or his campaign. Rather, I suspect that this is more about what a Trump presidency represents: the end of our politically correct society.

Why do people like me have to write anonymous blogs and columns on the internet when talking about the obvious reality of human biological differences (especially biological group differences)? Why do researchers face the risk of falling into The Bermuda Triangle of Science, as behavioral geneticist Brian Boutwell recently put it?

The academy, in general, is a wonderful place to work, but not everyone plays nice. Veer too far from carefully charted courses and someone may slip quietly up behind you and slide a cold piece of steel in between the ribs of your budding research career.

They’ll do this believing that they are serving public interest by snuffing out dangerous research agendas, but that won’t make any difference to you. It’ll be your reputation that will suffer grievous injury. What in the world might elicit such harsh rebuke from a community of otherwise broadminded, free speech spouting scholars? What is so verboten that it constitutes academia’s Bermuda Triangle, a place where careers disappear more often than ships in the actual Bermuda Triangle? In one word, it’s race.

[R]ace represents academia’s true Bermuda Triangle. Perhaps never has the topic of genetic ancestry been so important, yet despite its relevance, bright scholars continue to stay away from it in droves … It will not matter how noble you think your motives are, if you factor in race as a variable, your actions are subject to impeachment, and your reputation may be sacrificed as a burnt offering to our new religion.

Linda Gottfredson is a brilliant, productive, and innovative scholar. Dr. Gottfredson, however, found herself in the Bermuda Triangle some years back

crossing the boundaries of the Triangle (even if only to defend a colleague) can be frightening. Angry invectives hurled in your direction will come so fast, and so fierce, it will likely leave your head spinning, as Gottfredson illustrates (p.276):

News coverage was often lurid. The UD African-American Coalition argued that my work was not just offensive, but dangerous. My ‘‘so-called research” and the social policies I ‘‘was likely to propose” were ‘‘liable to threaten the very survival of African-Americans” (Tarver, 1990, p. 6A).

Within the Bermuda Triangle, you see, it is a free for all when it comes to accusations and motive indictment. There is no suitable defense, trying to mount in fact one will only fan the flames.

Such facts are effectively embargoed in our society, and anyone who breaks this taboo can face serious social consequences.

As John McWhorter put it in his piece Antiracism, Our Flawed New Religion:

One hearkens to one’s preacher to keep telling the truth—and also to make sure we hear it often, since many of its tenets are easy to drift away from, which leads us to the next evidence that Antiracism is now a religion. It is inherent to a religion that one is to accept certain suspensions of disbelief. Certain questions are not to be asked, or if asked, only politely—and the answer one gets, despite being somewhat half-cocked, is to be accepted as doing the job.

“Why is the Bible so self-contradictory?” Well, God works in mysterious ways—what’s key is that you believe. “Why does God allows such terrible things to happen?” Well, because we have free will … and it’s complicated but really, just have faith.

It stops there: beyond this first round, one is to classify the issues as uniquely “complicated.” They are “deep,” one says, looking off into the air for a sec in a reflective mode, implying that thinking about this stuff just always leads to more questions, in an infinitely questing Talmudic exploration one cannot expect to yield an actual conclusion.

Antiracism requires much of the same standpoint. For example, one is not to ask “Why are black people so upset about one white cop killing a black man when black men are at much more danger of being killed by one another?” Or, one might ask this, very politely—upon which the answers are flabby but further questions are unwelcome. A common answer is that black communities do protest black-on-black violence —but anyone knows that the outrage against white cops is much, much vaster.

Why? Is the answer “deep,” perhaps? Charles Blow, at least deigning to take the issue by the horns, answers that the black men are killing one another within a racist “structure.” That doesn’t explain why black activists consider the white cop a more appalling threat to a black man than various black men in his own neighborhood. But to push the point means you just don’t “get” it (you haven’t opened your heart to Jesus, perhaps?)

 
🔊 Listen RSS

Updated, 4/6/16. See below!

The 2016 U.S. presidential race has brought out a serious whirlwind of events, the likes of which haven’t been seen in a long time, if ever. Despite my own expectations for a boring campaign, this election cycle has been anything but. Most significant to this excitement has been the rise of Donald Trump – and, to a lesser extent, the rise of Bernie Sanders. Much has been said about these men, including much in an attempt to figure out what is behind their popularity. However, this election, particularly the battle against Trump, has taken on a larger scope, in ways that far exceed the man. The election is about grander issues. In good part, it is about the fate of the very character of the nation itself – and indeed, of all of Western society.

While there may be a perhaps an unprecedented series of events occurring in this election, there are nonetheless clear patterns to the vote, patterns we’ve seen before.

For one, the American nations (see American Nations Series) have played a large role in the 2016 presidential race. The reason for this, ultimately, is because demographic factors are what drives elections, at least in our era. Contrary to popular analysis (even that within the HBD sphere), the composition of a region’s population dictates said region’s vote – at least, much more so than situational factors such as economics, crime, or urbanicity. This is plainly obvious to the genetically informed, but is ignored by most mainstream discussion of politics. Mainstream sources struggle to find “environmental” factors that dictate the vote, and they run into trouble every time when they do.

None of this should be surprising, since we know that political views are highly heritable (from Hatemi et al, 2010):

Political chart heritability

There is minimal effect of “the environment” within cohorts (and the differences between cohorts is likely primarily situational). The way people vote is a reflection of who and indeed what they are. It has nothing to do with how they were raised by their parents, where they grew up, or where they live now (except to the extent current self-interest is involved). (See also The Behavioral Genetics Page, particularly the post The Son Becomes The Father.) To understand that vote, you must understand the people.

To quickly recap, the United States (and for that matter, Canada) is divided into several broad ethnocultural regions – nations if you will.

North American Nations 4 3

These regions exists thanks to the continuing legacy of the founding populations and the various assortative migrations (founder effects and boiling off) that have happened over the history of the country. This was described by Colin Woodard in his book American Nations. In my American Nations Series, I detail the various ways these nations are visible today as well as discuss their genetic roots.

In the present election cycle, the nations are playing a role. First, here is a map of support for Donald Trump across the country (from Nate Cohn).

Cc0G46rUsAAR3Y2

 

Many have dubbed this an “east vs. west” split (as opposed to usual north/south split typically seen), but it isn’t really that, as Trump has modestly strong support near the West Coast. Rather, we see that Trump is strong across the usual “Dixie” nations, the Tidewater, the Deep South, and especially Greater Appalachia. He also has fair support across Yankeedom, but is comparatively weak in the Midlands. There is a pronounced “hole” in Trump’s support, but a look at this second map shows precisely where:

US Personality

Trump is weak in the “Friendly & Conventional” zone of the country. This map is drawn from personality studies detailed in Rentfrow et al (2013). The “Friendly & Conventional” zone is an area high in extraversion, agreeableness, and conscientiousness and depleted in openness to experience (see Predictions on the Worldwide Distribution of Personality). A modern popular notion likes to lump together the interior of the country as the “Flyover Zone”, being universally Christian, conservative, and traditional. But the American nations maps and this one clearly show that that idea is too simplistic. These areas do vote strongly Republican in the general presidential election, but there is much more nuance than that.

For one, there is a key difference in the overall composition. Greater Appalachia is composed heavily of Ulster Scots, originally from the Anglo-Scottish border area. The Deep South and the Tidewater derive from the English Cavaliers from southwest England.

By contrast, the “Friendly & Conventional” zone is heavily German and Scandinavian in ancestry. Furthermore, the area has been heavily “boiled-off,” as more liberal and adventurous individuals have fled the area for decades, leaving a core of traditional and conservative individuals in its wake (as detailed in my post More Maps of the American Nations). These conservatives are quite unlike their Southern counterparts (see Genes, Climate, and Even More Maps of the American Nations):

 
🔊 Listen RSS

This page is to make an easy to use (and easy to share) central repository for my posts on the science of behavioral genetics. This is fundamental reading for anyone interested in HBD – indeed for anyone interested in the human sciences in general.

 

The Five Laws of Behavioral Genetics

The five laws of behavioral genetics are:

  1. All human behavioral traits are heritable
  2. The effect of being raised in the same family is smaller than the effect of the genes.
  3. A substantial portion of the variation in complex human behavioral traits is not accounted for by the effects of genes or families.
  4. A typical human behavioral trait is associated with very many genetic variants, each of which accounts for a very small percentage of the behavioral variability.
  5. All phenotypic relationships are to some degree genetically mediated or confounded.

All are simple. All can be said in one sentence. Yet all are incredibly profound and terribly underappreciated in today’s society.

For most of the history of the laws, there were only three. The first three were coined by Eric Turkheimer (who has since spent his time trying to undermine his own discovery). Recent genomic studies have added the fourth (Chabris et al, 2015). And Emil Kirkegaard has proposed the fifth based on multivariate behavioral genetic studies. Allow me to review the five laws and their everyday significance.

First Law: All human behavioral traits are heritable.

Derivation:

  • Identical twins raised apart will be similar – and usually highly similar in every conceivable measurement
  • More generally, behavioral and other phenotypic similarity is predicted by genetic similarity for all behaviors and phenotypes, across all human relations, regardless of environmental circumstances. That is, identical twins are more similar than fraternal twins or full siblings, who are more similar than half-siblings, who are more similar than first cousins, and so on ad infintum.

This is underappreciated because this means that all human characteristics, including the things we feel are products of “free choice” or “free will” are infact heavily dependent on genetic forces. This includes life circumstances, such as where and how you live – even how you grew up. Free will doesn’t exist. Political, religious, and moral views are themselves partly enshrined in the genes. This (or, more specifically, additive heritability) is responsible for continuity within families and within social and ethnic groups. And this is why human societies and behavioral quirks persist, resistant to change.

Second Law: The effect of being raised in the same family is smaller than the effect of the genes.

Derivation:

  • Identical twins raised apart are no less similar than identical twins raised together
  • Non-related individuals reared together are no more similar than random strangers
  • More generally, people growing up together are no more similar than you’d expect from their genetic relationship alone

Also under appreciated, the Second Law talks about the “shared environment” – parents, peers, schools, neighborhoods – all the things children growing up in the same household share. The effect of all those things on any behavioral trait or other phenotype is nil. Zip. Zilch. Nada. Zero. All the things people (especially in the modern West) think matter to children’s development have no effect at all. This includes expensive schools, nice homes, strict discipline, religious indoctrination – none of it matters. No adult outcome shows any effect of shared environment, this includes criminality, marital stability, income, adult happiness, and substance abuse (though note, educational attainment seems to be affected by shared environment, but even here, the effect of education goes away when you look at income). It just doesn’t matter. This strikes squarely against popular belief, making the second law the most vehemently denied of them all.

Third Law: A substantial portion of the variation in complex human behavioral traits is not accounted for by the effects of genes or families.

Derivation:

  • Identical twins (even raised together) are in fact far from identical and differ in significant ways
  • In general, there will be variance left over once genes and shared environmental effects are accounted for

Identical twins may have different handedness, have different fingerprints, and indeed, can differ in criminal history (such as perpetrating a mass shooting).

More poignantly, identical twins can (and in fact, in cases where at least one is gay, usually do) differ in sexual orientation.

Twins differ substantially for cancer incidence – despite having very similar lifestyle habits, indicating that these factors don’t do as much as many think.

 
• Category: Science 
🔊 Listen RSS

Little Miss Jay1 Little Miss Jay3Little Miss Jay4Little Miss Jay7Little Miss Jay 8

All photos by me. Joy to the world my friends!

 
🔊 Listen RSS

A persistent misunderstanding both in the world of HBD and general medical and psychological science at large is the notion of what constitutes a “disorder.” When does a phenotype represent a physiological or behavioral malady? For behavioral issues, most people regard the Diagnostic and Statistical Manual of Mental Disorders (DSM) as the “final word” on this matter. While the DSM does make some attempt to assess actual impaired functioning, its assessments are tinged by cultural biases. A key component of DSM diagnostic criteria is social judgement of what is “proper” – what constitutes a correctly behaving person, according to the current cultural values?

Indeed, the DSM’s own Wikipedia page captures a many of the book’s problems:

Various authorities criticized the fifth edition both before and after it was formally published. Critics assert, for example, that many DSM-5 revisions or additions lack empirical support; inter-rater reliability is low for many disorders; several sections contain poorly written, confusing, or contradictory information; and the psychiatric drug industry unduly influenced the manual’s content. Various scientists have argued that the DSM-5 forces clinicians to make distinctions that are not supported by solid evidence, distinctions that have major treatment implications, including drug prescriptions and the availability of health insurance coverage.

But its more basic problems go deeper than that.

For starters, what do we mean by a “disorder?” The word implies that something is “out of order” – that is, something is not working as “intended.” Now when we’re talking about living things, that “intended” function is the function that survived the cruel process of elimination that is natural selection. Hence, any concept of a behavioral or physiological disorder must be informed by evolutionary theory. Medicine and psychiatry need to incorporate Darwinian processes.

As I begin, I want to be clear that it should be understood that all human behavioral traits are heritable, with “nurture” as its commonly thought of playing a minimal role to nonexistent role in each (see also Environmental Hereditarianism, The Son Becomes The Father, and More Behavioral Genetic Facts). The rest of this post proceeds assuming an understanding of this reality.

However, the people making these assessments, even the “experts,” tend to be evolutionarily illiterate; that is, they have a poor understanding of evolutionary theory. This failing isn’t just academic; in addition to hindering the understanding the nature and origin of these phenotypes, ignorance of Darwinism leads to to difficulty managing and treating them.

This means that there are a host of phenotypes classified as “disorders” that in fact aren’t, as well as a good many that are in fact Darwinian disorders which are not classified as such.

My Twitter followers know that I have been making noise about this problem for some time. And now, enter Durisko, Mulsant, McKenzie, and Andrews, 2016, with their paper “Using Evolutionary Theory to Guide Mental Health Research,” published in The Canadian Journal of Psychiatry.

The authors (who I suspect have read my writing) sum up the problem excellently in their abstract:

Evolutionary approaches to medicine can shed light on the origins and etiology of disease. Such an approach may be especially useful in psychiatry, which frequently addresses conditions with heterogeneous presentation and unknown causes. We review several previous applications of evolutionary theory that highlight the ways in which psychiatric conditions may persist despite and because of natural selection. One lesson from the evolutionary approach is that some conditions currently classified as disorders (because they cause distress and impairment) may actually be caused by functioning adaptations operating “normally” (as designed by natural selection). Such conditions suggest an alternative illness model that may generate alternative intervention strategies. Thus, the evolutionary approach suggests that psychiatry should sometimes think differently about distress and impairment. The complexity of the human brain, including normal functioning and potential for dysfunctions, has developed over evolutionary time and has been shaped by natural selection. Understanding the evolutionary origins of psychiatric conditions is therefore a crucial component to a complete understanding of etiology.

Durisko et al produce a neat chart that analyzes examples:

Disorders

 

The sad fact of the matter is that there are some disorders the medical and psychiatric communities are correct in calling disorders but these communities are ignorant about why they are correct. These lead me to the first major cause of mental disorders.

A major challenge any functioning organism faces is genetic load. This is the burden of deleterious mutations that we all carry. For a discussion of this, see Greg Cochran over at West Hunter:

Typos
Get Smart
More thoughts on genetic load
The genetics of stupidity
The Golden Age

Intellectual Ambergris

In short, new mutations always arise. The majority of these mutations are neutral or harmful to fitness. Deleterious alleles are selected out at a rate proportional to their fitness impact; the bigger the fitness hit, the faster they are selected out. This means that alleles with mild fitness impacts can persist for many generations. Certain individuals can have more than their fair share of the these deleterious alleles. In some cases, this leads to mental illness – when there are just one too many things “broken” in the brain. While the individual alleles that are causal to these illnesses are all rare and are all being selected out, new mutations continue to arise, hence, the illness persists in the population – each instance being genetically distinct from all the others.

Mathew Keller and Geoffery Miller detailed how this applies to mental illness in their 2006 paper. Genetic load largely* explains mental illnesses such as autism, schizophrenia, and bipolar disorder.