Has eliminating hookworms made people fatter?

Okay, yes, obviously when you take the gut parasites out of people, they tend to gain weight immediately after. That’s not exactly what I’m talking about.

First, let’s assume you come from a place where humans and hookworms have co-existed for a long, long time. The hookworms that just about everybody in the American South used to have appear to have come from Africa, so I think it safe to assume that hookworms have probably been infecting a lot of people in Africa for a long time. I don’t know how long–could be anywhere from a few hundred years, if they’d come from somewhere else or recently mutated or something, or could be tens of thousands or hundreds of thousands of years, if they’ve just always been hanging around. Let’s just go with tens of thousands, because if it wasn’t them, it was probably something else.

Over a few thousand years of constant infection, you’d expect to develop some sort of biological response to minimize the chances of death–that is, your ancestors would have evolved over time to be less susceptible to the parasite. Obviously not getting the parasite is one great way to avoid getting killed by it, but let’s assume that’s not an option.

Another solution would be to just absorb food differently–faster, say, or in a manner that circumvents the parts of the gut that are normally infected. Over time, humans and parasites might tend toward an equilibrium–humans stepping up their digestion to make up for what’s lost to the parasite.

Remove the parasite, and equilibrium is lost: suddenly the human starts gaining a lot of weight, especially compared to people from populations that did not adapt to the parasite.

That functional a gut isn’t needed anymore, but it might persist for a while if there are no counter-evolutionary pressures.

White Women’s Tears

Did you know that white women cry a lot? And that it annoys the crap out of black women? I didn’t, either, but “White women’s tears” is a thing SJWs and anti-racists actually talk about. Apparently black women hate it when white women cry.

Some quotes from around the internet:

Serena Williams Drinks, Bathes In, And Makes Lemonade With White Tears:

NOTE: That subtitle is from the article, NOT from me. The person who wrote the article is claiming that Serena Williams makes tear-ade, not me.

Some people even write scholarly articles on the subject, eg, “When White Women Cry: How White Women’s Tears Oppress People of Color” (PDF)

Betcha didn’t know that crying is a form of oppression.

The general sentiment is not just that white women cry a lot, but also that they do it specifically to avoid getting blamed for racism–like “crocodile tears,” implying that the emotions behind them are not real:

From the Urban Dictionary

 

Personally, I’d never given tears a second thought (other than not particularly liking them,) until I stumbled upon these sorts of comments. If I cry, it’s because of emotions, not because I’m trying to avoid blame.

But I suspect these black ladies are actually on to something. White women probably do cry more than black women. No, not to get out of being called racist; they cry because they’re biologically inclined to deal with conflict by crying.

Peter Frost speculates that whites, particularly white women, have been selected for neotenous traits, like pale skin and hair. (Frost has a ton of posts on the subject, so I’m not going to link to them all; you can just go read his blog if you want the details on his argument. I’m summarizing as relevant here; please forgive me if I’ve accidentally mixed in some arguments from West Hunter; it’s hard to keep my thoughts tagged with original authors for too long.)

This implies that white women are more neotenous than black women.

In many traditional African societies, women basically raise their children on their own/with the help of their kin networks, leading probably to a genetic preference for polygyny rather than monogamy and a personality type that we might characterize as strong, independent women. As I have previously noted, these societies happen to be very likely ancestral to much of the US’s African population.

By contrast, the cold, harsh winters of the northern European climate forced people into monogamous relationships in which the men did a lot of the back-breaking agricultural labor. Actually, Frost argues that it started before the advent of agriculture, but with mate selection on the ice age steppes:

“It seems that this evolution took place between 20,000 and 10,000 years ago—long after modern humans had arrived in Europe some 40,000 years ago. This is when Europeans acquired their most visible features: white skin, multi-hued eyes and hair, and a more childlike face shape. In my opinion, such features were an adaptation not to weak sunlight but to a competitive mate market where men were scarce because they were less polygynous and more at risk of early death. This situation prevailed on the European steppe-tundra of the last ice age, whose high bio-productivity made possible a relatively large human population at the cost of a chronic oversupply of mateable women. The result was an unusually intense degree of sexual selection.”

The problem with living in close proximity to men is that men are violent and aggressive. Luckily, men appear to already have a neural subroutine for decreasing aggression: look/act like a baby. Being around babies or small children appears to make men less aggressive/reduces the quantity of the sorts of hormones that lead to aggression, which leads in turn to men being less likely to murder their own children.

The development of neotenous features in women thus both increased the chances of men bonding with them and wanting to care for them (the neural subroutine for bonding with and caring for children hopefully does not require discussion,) and  decreased their chances of being victims of male aggression as proximity increased.

Crying is chiefly a characteristic of babies and small children. Grownups cry far less; men have historically prided themselves (for better or worse) on not crying.

Tears are, for white women, an effective means of decreasing white male aggression. I’m not saying they’re a conscious strategy (though of course sometimes they are.) I’m saying that for thousands of years, white women who cried more were less likely to die childless than women who cried less. So most of the time, when they start to cry, it’s unintentional–they can’t help it. That’s just how they’re wired.

(Note: You don’t have to buy Frost’s line of reasoning to believe that white women cry more than black women; Greg Cochran attributes neotenous white features to selective pressure on white men to behave themselves in large social groups–the idea that “civilization” “domesticated” people; Rushton links longer infancy and childhood and late retention of neotenous features to brain development. There are many potential explanations, but one thing that does seem to be widely agreed upon is that whites are more neotenous than blacks.)

White women cry even when race isn’t being discussed (though this may not be obvious if your only interaction with white women is via SJW/anti-racist communities, where racism and women dominate almost all discussions.) White women love “tear jerker” movies, romance novels and women’s fiction, and all designed to make them cry. They weep over the Pope’s latest pronouncements. They cry about their hair and their weight and their makeup and just about anything, really. They probably even cry if you criticize their lab results. (Of course, if it’s a white dude who’s done nothing to contribute to the advancement of humanity but win a Nobel Prize in Physiology / Medicine for his discoveries of protein molecules that control cell division who says that white women cry [let’s not kid ourselves about the skin tones of most women in science,] then you’re an evil sexist woman-oppressor, rather than a brave social justice warrior helping create our new and better future by calling out racist white women for derailing the conversation.)

Black women, by contrast, haven’t been subject to the same neotenizing pressures. They simply aren’t wired to cry at the drop of a hat. To them, white women are acting like whiny babies:

and thus the contempt for “white women’s tears.”

“If you can’t say something nice, don’t say anything at all”

Back in anthropology class, we talked rather extensively about ethics–specifically, What if you write things that hurt the people you’re studying?

Take the Yanomami (also spelled Yanomamo, not to be confused with the Yamnaya.) While there is some dispute over why the Yanomami are violent, and they probably aren’t the most violent people on Earth, they certainly commit their fair share of violence:

See also my post, “No, Hunter Gatherers were not Peaceful Paragons of Gender Egalitarianism.“

In 1967, anthropologist Napoleon Alphonseau Chagnon published Yanomamö: The Fierce People, which quickly became a bestseller, both for anthropology students and the popular public. On the less scholarly side, Ruggero Deodato released the horror film “Cannibal Holocaust” in 1980, fictional account of Yanomami cannibalism. I have truly never understood the interest in or psychology behind the horror genre, but apparently the film has been banned in 50 countries and highly regarded by people who like that sort of thing–Total Film ranked it the tenth greatest horror film of all time, Wired included it in its list of the top 25 horror films, and IGN ranked it 8th on its list of the ten greatest grindhouse films–so I assume that means it was very horrific and very popular.

Aside from allegations that the anthropologists themselves gave/traded the Yanomami a bunch of weapons that resulted in a big increase in the number of deaths, there are claims that, due to the Yanomamis’ violent reputation, miners in the area have opted to just shoot them on sight. The Yanomami are a rather small, isolated people with no political power to speak of, little immunity to Western diseases, and a lot of negative interactions with miners.

In a more mundane example, an anthropologist I spoke with referred to widespread illegal drug use among a people they had lived with. No one wants to cause legal trouble for their friends/companions/hosts–getting people arrested after they opened their homes and lives to you would be really shitty. But the behavior remains. None of us is perfect; every group does things that other people disapprove of or that would not look so great if someone wrote it down and published it.

The Thumper approach–that most favored by Americans, I suspect–is to just try not to say anything that might be perceived as not-nice. Report all of the good, and just leave out the bad.

My inner Kantian insists that this is lying, and that lying is bad. Maybe I can gloss over illegal drug use, but if I write a book about the Yanomami and don’t mention violence, I am a baldfaced liar, and you, my reader, should be mad at me for deceiving you. If I am in the business of describing humans and fail to do so, then like a stool with two legs, I am not doing my job.

The other solution I see people employ is to dress up all of the potentially negative things in dry, technical language so that normal people don’t notice. This would be the opposite of making a movie like Cannibal Holocaust. We use terms like “genetic introgression” and “affective empathy” and “clades,” which people who don’t generally read technical materials on the subject tend not to be familiar with.

But there are times when there are no two ways about it–there are no polite, responsible ways to disguise the truth, you don’t want to lie, and you genuinely don’t want to cause distress or trouble for anyone.

We never came up with a solution back in class. I still don’t have one.

Making Sense of Maps–violence and grain

So I was looking at this map, trying to figure out what might be causing different rates of violence:

No data for non-EU countries like Norway and Russia

Clearly it’s not degree of Germaness, as the Germans have less (reported) violence than their cousins in France, the UK, and Denmark. Doesn’t look like a Hajnal line effect, as France is solidly inside the line and Greece isn’t. Doesn’t look like latititude, is Ireland and Denmark and Latvia are all around the same latitude. Probably not an immigration thing, as it’s a stretch to blame violence against half of Denmark’s women on whatever relatively small % of the population is immigrants, while Spain and Italy (which I’m sure also have immigrants) are down in the 20%s.

Then I thought, aside from Ireland, it does look rather like a map of when grain arrived in Europe. Maybe the violence is fueled by alcohol, and groups that have been exposed to alcohol for longer are more resistant to its effects. (And Ireland, btw, does not have as much of an alcohol problem as is generally claimed.)

So here is a map of the spread of wheat in Europe:

From Science News: Wheat Reached England before Farming

Since grain originated (as far as Europe is concerned) in Turkey, I suspect that it became a dominant dietary staple faster after introduction in Spain, whose climate is probably similar to Turkey, than in more northerly places like Scotland or Finland. Ireland does not appear to lag significantly behind England, but northern Scotland does. Sadly, this map does not show us the Baltic and Scandinavia, where I gather the hunter-gatherer-fisher-herder lifestyle held on much longer.

Here is another map, of alcohol-related deaths:

source

This map sheds some light on why the UK comes out with more violence than Ireland: the Scottish. The English look pretty okay overall, but the Scots apparently get drunk and beat their wives with the vigor of, well, I guess the French.

I’d really like to see more complete versions of these maps, but oh, well. (Though I’m glad they left off Russia, which I suspect would change the scale on the graph, compressing the rest of the data into uselessness.)

Here are my suspicions: Grain (particularly wheat) started out over in Turkey and spread to Greece, Italy, Spain, the south-Slavic regions, southern French coast, and Germany, in about that order. These areas all seem to have low rates of domestic violence and, except for the Slavs, low rates of alcohol-fueled death. Perhaps the stats on that reflect differences in density or drunk driving laws, or the later admixture of another population like the Magyars that has less alcohol tolerance. East Germany clearly stands out as an anomaly that is probably due to the Cold War.

Wheat farming reached northern Europe later, reaching Scotland, Denmark, the Baltic, and Scandinavia last. Lower rates of alcohol-related death in some of these spots probably reflect people driving drunk less often due to local factors.

According to “investoralist”, in “The geo-alcohol belts of Europe,” “Episodic drunkenness seems embedded in the Nordic culture, so much so that most Scandinavian states have outrageously high alcohol taxes to discourage binge-drinking.  In a country where alcohol is the most common cause of death among working-aged adults, Finland raised its alcohol taxes twice in the 2008-2009 period.”

He further quotes, “[W]hen Finns drink, they drink heavily. The important thing is that I believe that they are not only drinking away their cultural neurosis; they actually value the cathartic effect of Dionysian drinking. This leads to a situation where, as I have put it, you can’t single out the alcoholics at our parties because everyone is as dead-drunk as alcoholics. This leads to a cultural tradition where drunkenness is positively valued among rather large segments of the population. Therefore, there exists no cultural consensus regarding the positive effects of moderation.”

According to the Wikipedia article on binge drinking, Denmark has the most binge drinkers.

Oh look:

Is this a map of where Scandinavians (and Germans) settled in the US?

Your thoughts?

The Good Side of Clannishness

So I was reading a conversation over at HBD Chick’s the other day about why some people take her work way too personally (and confrontationally,) even though it clearly isn’t meant that way, in which someone pointed out that even if she doesn’t exactly mean it that way, if you call people clannish or tribal, they’re bound to get offended, because nobody likes clannishness.

But wait, I thought. I know people who like clannishness.

This seems obvious when you consider that the majority of people who live in societies-that-are-more-clannish-than-mine probably like their societies and prefer their level of clannishness to my society’s level, otherwise they would take steps to change their society. Even if they might balk at the words like “clannish” or “tribal” (or the insinuation that their society has higher levels of in-breeding than some other society,) there are plenty of practical aspects of clannishness that some people actually like.

In the clannish society, you can depend on your extended kin network to always have your back. Clannish societies are generally very friendly–compare the outgoing friendliness of southern Italians to the more reserved-natured Germans. People with strong kin networks are born with a supply of friends, role models, advice givers, and potential business partners. Their kinfolk will even stick up for them, defending them against outsiders.

The inverse of clannishness is atomization, and atomization is lonely and stressful. In the atomized society, you are stuck on your own, with no one to catch you if you fall. You might be a single mother or an only child, or a hikikomori. Either way, you’re alone–and most people don’t seem to cope well with loneliness.

(The downside to tribal societies is that friendly extroverts are more likely to punch you in the face.)

Several of my friends have visited or lived in societies that fall outside the Hajnal Line, and absolutely loved them. “The friendliest place I have ever been,” raved one. “The people there are so friendly, I hear they’d stop and talk to their neighbors on the way to the hospital!” said another. “I just got hit on for the first time in my life,” said a third. “The only place I have ever felt what it meant to have a loving family–if only my family were like that.” “Everyone was so hospitable and polite and absolutely mortified when my hotel got bombed.” “If it weren’t for my [obligations], I would move there in a heartbeat.” (Quotes from five different places.)

Some of these same people have gone through decades of loneliness in outbred societies. One friend had literally no friends for a decade, after losing a spouse to a divorce and a child and parent to death; two are considered unattractive and are perennially alone. Several have little to no relationship with their extended families; most live quite far from their nearest relatives.

So even if people may not like being called “clannish” or “tribal,” these societies certainly have their fans.

Is Acne an Auto-Immune Disorder?

Like our lack of fur, acne remains an evolutionary mystery to me.

Do other furless mammals get acne? Like elephants or whales? Or even chimps; their faces don’t have fur. If so, everyone’s keeping it a secret–I’ve never even seen an add for bonobo anti-acne cream, and with bonobos’ social lives, you know they’d want it.🙂

So far, Google has returned no reports of elephants or whales with acne.

Now, a few skin blemishes here and there are not terribly interesting or mysterious. The weird thing about acne (IMO) is that it pops up at puberty*, and appears to have a genetic component.

Considering that kids with acne tend to feel rather self-conscious about it, I think it reasonable to assume that people with more severe acne have more difficulty with dating than people without. (Remember, some people have acne well into their 30s or beyond.)

Wouldn’t the non-acne people quickly out-compete the acne-people, resulting in less acne among humans? (Okay, now I really want to know if someone has done a study on whether people with more acne have fewer children.) Since acne is extremely common and shows up right as humans reach puberty, this seems like a pretty easy thing to study/find an effect if there is any.

Anyway, I totally remember a reference to acne in Dr. Price’s Nutrition and Physical Degeneration, (one of my favorite books ever,) but can’t find it now. Perhaps I am confusing it with Nutrition and Western Disease or a book with a similar title. At any rate, I recall a picture of a young woman’s back with a caption to the effect that none of the people in this tropical local had acne, which the author could tell rather well since this was one of those tropical locals where people typically walk around with rather little clothing.

The Wikipedia has this to say about the international incidence of acne:

“Rates appear to be lower in rural societies. While some find it affects people of all ethnic groups, it may not occur in the non-Westernized people of Papua New Guinea and Paraguay.

Acne affects 40 to 50 million people in the United States (16%) and approximately 3 to 5 million in Australia (23%). In the United States, acne tends to be more severe in Caucasians than people of African descent.”

I consider these more “hints” than “conclusive proof of anything.”

Back when I was researching hookworms, I ran across these bits:

“The [Hygiene Hypothesis] was first proposed by David P. Strachan who noted that hay fever and eczema were less common in children who belonged to large families. Since then, studies have noted the effect of gastrointestinal worms on the development of allergies in the developing world. For example, a study in Gambia found that eradication of worms in some villages led to increased skin reactions to allergies among children. … [bold mine.]

Moderate hookworm infections have been demonstrated to have beneficial effects on hosts suffering from diseases linked to overactive immune systems. … Research at the University of Nottingham conducted in Ethiopia observed a small subset of people with hookworm infections were half as likely to experience asthma or hay fever. Potential benefits have also been hypothesized in cases of multiple sclerosis, Crohn’s Disease and diabetes.”

So I got to thinking, if allergies and eczema are auto-immune reactions (I know someone in real life, at least, whose skin cracks to the point of bleeding if they eat certain foods, but is otherwise fine if they don’t eat those foods,) why not acne?

Acne is generally considered a minor problem, so people haven’t necessarily spent a ton of time researching it. Googling “acne autoimmune” gets me some Paleo-Dieter folks talking about curing severe cases with a paleo-variant (they’re trying to sell books, so they didn’t let on the details, but I suspect the details have to do with avoiding refined sugar, milk, and wheat.)

While I tend to caution against over-enthusiastic embrace of a diet one’s ancestors most likely haven’t eaten in thousands or ten thousand years, if some folks are reporting a result, then I’d love to see scientists actually test it and try to confirm or disprove it.

The problem with dietary science is that it is incredibly complicated, full of confounds, and most of the experiments you might think up in your head are completely illegal and impractical.

For example, scientists figured out that Pellagra is caused by nutritional deficiency–rather than an infectious agent–by feeding prisoners an all-corn diet until they started showing signs of gross malnutrition. (For the record, the prisoners joined the program voluntarily. “All the corn you can eat” sounded pretty good for the first few months.) Likewise, there was a program during WWII to study the effects of starvation–on voluntary subjects–and try to figure out the best way to save starving people, started because the Allies knew they would have a lot of very real starvation victims on their hands very soon.

These sorts of human experiments are no longer allowed. What a scientist can do to a human being is pretty tightly controlled, because no one wants to accidentally kill their test subjects and universities and the like don’t like getting sued. Even things like the Milgram Experiments would have trouble getting authorized today.

So most of the time with scientific studies, you’re left with using human analogs, which means rats. And rats don’t digest food the exact same way we do–Europeans and Chinese don’t digest food the exact same way, so don’t expect rats to do it the same way, either. An obvious oversight as a result of relying on animal models is that most animals can synthesize Vitamin C, but humans can’t. This made figuring out this whole Vitamin C thing a lot trickier.

Primates are probably a little closer, digestively, to humans, but people get really squeamish about monkey research, and besides, they eat a pretty different diet than we do, too. Gorillas are basically vegan (I bet they eat small bugs by accident all the time, of course,) and chimps have almost no body fat–this is quite remarkable, actually. Gorillas and orangutans have quite a bit of body fat, “normal” levels by human standards. Hunter-gatherers, agriculturalists, and sedentary butt-sitters like us have different amounts, but they still all have some. But chimps and bonobos have vanishingly little; male chimps and bonobos have almost zero body fat, even after being raised in zoos and fed as much food as they want.

Which means that if you’re trying to study diet, chimps and bonobos are probably pretty crappy human analogs.

(And I bet they’re really expensive to keep, relative to mice or having humans fill out surveys and promise to eat more carbs.)

So you’re left with trying to figure out what people are eating and tinker with it in a non-harmful, non-invasive way. You can’t just get a bunch of orphans and raise them from birth on two different diets and see what happens. You get people to fill out questionnaires about what they eat and then see if they happen to drop dead in the next 40 or 50 years.

And that doesn’t even take into account the fact that “corn” can mean a dozen different things to different people. Someone whose ancestors were indigenous to North and South America may digest corn differently than someone from Europe, Africa, or Asia. Different people cook corn differently–we don’t typically use the traditional method of mixing it with lime (the mineral), which frees up certain nutrients and traditionally protected people from Pellagra. We don’t all eat corn in the same combinations with other foods (look at the interaction between the calcium in milk and Vitamin D for one of the ways which combining foods can complicate matters.) And we aren’t necessarily even cooking the same “corn”. Modern hybrid corns may not digest in exactly the same way as corn people were growing a hundred or two hundred years ago. Small differences are sometimes quite important, as we discovered when we realized the artificially-created trans-fats we’d stuck in our foods to replace saturated fats were causing cancer–our bodies were trying to use these fats like normal fats, but when we stuck them into our cell walls, their wonky shapes (on a chemical level, the differences between different kinds of fats can be mostly understood that they are shaped differently, and trans fats have been artificially modified to have a different shape than they would have otherwise,) fucked up the structure of the cells they were in.

In short, this research is really hard, but I still encourage people to go do it and do it well.

 

Anyway, back on topic, here’s another quote from the Wikipedia, on the subject of using parasites to treat autoimmunie disorders:

“While it is recognized that there is probably a genetic disposition in certain individuals for the development of autoimmune diseases, the rate of increase in incidence of autoimmune diseases is not a result of genetic changes in humans; the increased rate of autoimmune-related diseases in the industrialized world is occurring in too short a time to be explained in this way. There is evidence that one of the primary reasons for the increase in autoimmune diseases in industrialized nations is the significant change in environmental factors over the last century. …

Genetic research on the interleukin genes (IL genes) shows that helminths [certain kinds of parasites] have been a major selective force on a subset of these human genes. In other words, helminths have shaped the evolution of at least parts of the human immune system, especially the genes responsible for Crohn’s disease, ulcerative colitis, and celiac disease — and provides further evidence that it is the absence of parasites, and in particular helminths, that has likely caused a substantial portion of the increase in incidence of diseases of immune dysregulation and inflammation in industrialized countries in the last century. …

Studies conducted on mice and rat models of colitis, muscular sclerosis, type 1 diabetes, and asthma have shown helminth-infected subjects to display protection from the disease.”

 

Right, so I’m curious if acne falls into this category, too.

Christianity and the Rise of the Art Instinct

I think there’s a book by the title of “The Art Instinct.” I haven’t read it.If anyone knows of any good sources re human genetics, art, and history, I’d be grateful.

As far as I know, some kind of art exists in all human populations–even Neanderthals and other non-AM primates like homo Erectus, I think, appear to have had occasional instances of some form of art. (I am skeptical of claims that dolphins, elephants, and chimps have any real ability to do art, as they do not to my knowledge produce art on their own in their natural habitats; you can also teach a gorilla to speak in sign language, but it would be disingenuous to suggest that this is something that gorillas naturally do.)

However, artistic production is clearly not evenly distributed throughout the planet. Even when we only consider societies that had good access to other societies’ inventions and climates that didn’t destroy the majority of art within a few years of creation, there’s still a big difference in output. Europe and China are an obvious comparison; both regions have created a ton of beautiful art over the years, and we are lucky enough that much of it has been preserved. But near as I can tell, Europeans have produced more. (People in the Americas, Australia, etc., did not have historical access to Eurasian trade routes and so had no access to the pigments and paints Europeans were using, but people in the Middle East and China did.)

Europeans did not start out with a lot of talent; Medieval art is pretty shitty. European art was dominated by pictures of Jesus and Mary to an extent that whole centuries of it are boring as fuck. Even so, they produced a lot of it–far more than the arguably more advanced cultures of the Middle East, where drawing people was frowned upon, and so painting and sculpture had a difficult time getting a foothold.

I speculate that during this thousand years or so of shitty art, the Catholic Church and other buyers of religious paintings effectively created a market that otherwise wouldn’t have existed otherwise (especially via their extensive taxation scheme that meant all of Europe was paying for the Pope to have more paintings. The (apparently insatiable) demand for religious paintings meant employment for a lot of artists, which in turn meant the propagation of whatever genes make people good at art (as well as whatever cultural traits.) After 700 or a thousand years or so, we finally see the development of art that is actually good–art that suggests some extraordinary talent on the part of the artist.

I further speculate that Chinese art has been through a similar but slightly less extensive process, due to less historical demand, due to the historical absence of an enormous organization with lots of money interested in buying lots of art. Modern life may provide very different incentives, of course.

Thus the long period of tons of boring art may have been a necessary precursor to the development of actually good art.

“Ancestral Microbes”

Since misconceptions bug me, I figure a reasonable way to fix them is to point them out when I see them. Most of these are probably misconceptions I once held, which explains why I am sensitive to them.

Today, “ancestral” microbes. From Hawks:

“Yong also includes a nice discussion of the misconception of “ancestral” or “more ancient” as applied to microbial diversity:

“”Hold on, though. The Hadza and the Matses are not ancient people, and their microbes are not “ancient bacteria”, as one headline stated. They are modern people, carrying modern microbes, living in today’s world, and practicing traditional lifestyles. It would be misleading to romanticise them and to automatically assume that their microbiomes are healthier ones.””

Hawk also notes, “A naive prediction from community ecology would be that a harmful element disrupting the microbiome should restrict its diversity, not increase it. But from the view of the microbes, the parasites add nutrients to the gut system by extracting more energy from the host, creating opportunities for microbial niches that may not be there in a healthy gut. Your microbiome is not all about you, after all.”

You Probably Aren’t Adapted to the Paleo Diet

Sorry, guys.

Look, I like the Paleo Diet as much as you do–maybe even more than you do. After all, I didn’t name this blog Evolutionist X because I haven’t been reading about paleolithic peoples.

The basic idea of the Paleo Diet–in case you’ve been living under a rock–is that you will be healthier if you eat only veggies, fruit, and meat (no grains or milk products,)–the diet your Paleolithic ancestors evolved to eat.

The problem with the Paleo Diet is that evolution did not stop 10,000 years ago. Evolution is constant. It doesn’t stop. You are not a caveman in a suit. You are a modern person. Unless your grandparents were hunter-gatherers, chances are good that your ancestors have been under significant evolutionary pressure to adapt to agriculture for thousands of years.

For example, Lactase Persistence evolved in dairying populations entirely within the last 10,000 years. Today, 80% of Europeans and European-descended people have the gene for lactase persistence. Outside of traditionally dairying areas, this trait is rare. It has spread entirely in response to the development of dairying–which means that if your ancestors have been raising animals for their milk for the past few thousand years, there is a very good chance that you are adapted to drinking milk well after infancy.

Of course, you’re probably not going to hurt yourself drinking water instead.

Likewise for wheat; if your ancestors have been eating wheat for thousands of years, you can probably digest it okay. If your ancestors haven’t been eating wheat for thousands of years, then you might want to avoid it–a Vietnamese friend of mine gets stomach aches from eating wheat (especially whole wheat, which contains more of the irritating chemicals from the external part of of the grain, designed to inspire your stomach to pass out the seed within without digesting it). Their ancestors ate rice, not wheat, so this is hardly surprising. (They also are lactose intolerant, since their ancestors did not keep dairy cows.) However, they have no difficulties digesting rice–a food they are adapted to eat.

If you aren’t adapted to wheat, wheat will give you a stomach ache. If wheat gives you a stomach ache, avoid it! But if your ancestors ate wheat and it doesn’t give you a stomach ache, you’ll probably be safe eating it.

It is reasonable to ask whether there are long-term bad effects from eating wheat or drinking milk–some disease that doesn’t kick in until you’re in your 70s, for example, would be difficult to develop adaptations to combat because it kills you after you’ve already had all of your kids. On this count, I would love to see more research.

Also, there may be some people who, like the 20% or so of Europeans who lack lactase persistence, are particularly sensitive to various foods. People with the ApoE4 gene (the “Alzheimer’s Gene”) may benefit from specific dietary modifications.

However, there’s no particular reason to believe that you are all that well-adapted to eating a diet your ancestors haven’t eaten in thousands of years.

Theory: Americans are fat because we don’t eat enough

I’ve long had a theory that dieting makes people gain weight. Just think about it for a second: at the very least, the correlation is tremendous.

Lots of studies have shown that diets are pretty useless–people tend, on average, to lose little to no weight on them. The whole diet industry, from diet sodas to lite beer to Weight Watchers, is, of course, basically a fraud.

The reasons are probably simple: One, humans have evolved no mechanisms to resist eating whenever possible. Your ancestors are people who ate when they could, not people who were indifferent to food, especially not tasty food*. And two, we live in a society with abundant, cheap, delicious food. Chances are good you’ve never even lived through a famine, much less had to go without for significant periods every few years of your life.

*Or have we?

I have watched people try to diet (mostly relatives.) The process goes something like this:

1. Relative declares, “I am going to lose weight for sure this time!”
2. Eats meager breakfast of oatmeal and apples.
3. Eats more apples for snack.
4. Comes over to my house, devours all my chips.
5. Weight-loss fails.

(A lot of people claim that you are supposed to feel “full” using various diet methods, but I’ve watched this happen enough times to enough different people to suspect that it’s a pretty common scenario.)

So tonight I was getting a bowl of icecream for a sick kiddo. Normally when getting icecream, I sneak a bite at the end. I can’t eat a full bowl of icecream, because hypoglycemia, but the taste is very tempting. But tonight, I looked at the icecream, and said, “No, I don’t want icecream.” What the hell was wrong with me? I’d just eaten a bowl of beans + cheese. I was full.

I suspect that our willpower, our ability to resist the kinds of foods that we can basically all agree aren’t really great to be eating, goes completely down the drain when we are hungry. And people are most likely to be hungry when they are dieting. So if you eat nothing but apples for breakfast, then somewhere along the way, you’re likely to eat nothing but cookies for dinner. But a solid breakfast of eggs, toast, and even a little bacon will probably leave you feeling full and happy, rendering temptation less, well, tempting.