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It's No Coincidence That Hitler Was a Germaphobe
Hitler appeared to have been highly sensitive to disgust, and research shows this trait is linked to numerous dimensions of ideology.
Hitler seemed obsessed with the idea of infection. The Nazi leader was, by most accounts, a germaphobe who avoided personal contact and bathed incessantly. He was repelled by sex, horrified by venereal disease. He referred to himself as an Einsiedler – a hermit. He extolled the virtues of celibacy and claimed prostitution was for inferior races, though some have proposed Hitler himself contracted syphilis from a Jewish prostitute in Vienna in 1908.
It was in ideology, however, where Hitler's obsession with infection thrived, becoming the essential Nazi metaphor: Germany was the body, Jews were the parasites.
Examples are abundant in his speeches and writings:
“How many diseases have their origin in the Jewish virus! We shall regain our health only be eliminating the Jew.”
“Anyone who wants to cure this era, which is inwardly sick and rotten, must first of all summon up the courage to make clear the causes of this disease.”
“This is the battle against a veritable world sickness which threatens to infect the peoples, a plague that devastates whole peoples...an international pestilence.”
“The Jew is a parasite in the body of other nations.”
“Germany, without blinking an eyelid, for whole decades admitted these Jews by the hundred thousand. But now… when the nation is no longer willing to be sucked dry by these parasites, on every side one hears nothing but laments.”
“If this battle should not come...Germany would decay and at best sink to ruin like a rotting corpse.”
Do Hitler's germaphobic tendencies and obsession with the infection metaphor reveal anything about his personality traits? While it's impossible to know for sure, it seems likely that he was highly sensitive to disgust.
Over the past couple of decades, studies have linked disgust sensitivity to numerous dimensions of ideology – immigration, political affiliation, sense of justice. If Hitler ranked high on the disgust scale, there were probably deeply rooted psychological forces lurking underneath his xenophobia and murderous fantasies that research on the behavioral immune system might help bring to light.
How disgust relates to personality and ideology
Disgust is a protective emotion. It causes us to lurch back from a rotten apple, or take an extra big step over dog poop on the sidewalk. These reactions are part of the behavioral immune system, which evolved to help us detect and avoid things in our environment that cause disease. That’s why we find some things universally repulsive – urine, feces, vomit.
What’s strange, however, is that an acute sense of disgust can extend beyond these things and into the social world, causing some to feel repulsed by certain ethnic groups. This might have once served an evolutionary function: In earlier times, it was probably useful to be wary of unfamiliar individuals or groups because they might have carried disease.
Today, this same evolutionary function might be playing a role in the immigration debate. According to a recent paper, people who are acutely sensitive to disgust are more likely to oppose immigration. The researchers explained:
It is the presence of physically and culturally distinct immigrants that poses a threat to individuals concerned about pathogens, not the intentions of the immigrants. Second, individuals motivated by pathogen avoidance are especially motivated to avoid contact with immigrants, potentially preventing the sorts of experiences that may engender tolerance. Taken together, these findings demonstrate that the behavioral immune system emerges as a potent—and distinct—obstacle to inclusive attitudes and tolerance.
Other studies have linked high disgust sensitivity to:
Hitler arguably qualifies for almost every dimension to which high disgust sensitivity is linked. Professor of Psychology Jordan Peterson elaborates on the connection between disgust and Nazism in the video below, about an hour into the lecture:
Still, how could one leader's disgust-oriented rhetoric have influenced an entire country?
Metaphor and the Final Solution
The Jew is the parasite of humanity. He can be a parasite for an individual person, a social parasite for whole peoples, and the world parasite of humanity. – Excerpt from "The Jew as World Parasite," a Nazi propaganda pamphlet
The use of metaphoric language in Nazi Germany has been studied at length since the end of World War II. On a psychological level, the dehumanization of the Jewish population through language was crucial in carrying out the Final Solution because deeming the Jews to be rats or parasites made extermination the logical and “necessary” course of action.
(A Nazi propaganda video compares the Jewish population to rats and parasites)
Some have considered the Nazi use of metaphorical language to be a “rhetorical trick,” a cynical manipulation of the cultural conversation to advance a murderous fantasy. But others, like Andreas Mulsoff, who penned Metaphor, Nation and the Holocaust, thought Hitler’s parasite metaphor sat at the bedrock of his ideology, conveying his “fundamental cognitive processes” and serving as an “integral part of the ideology that made the holocaust happen.”
In his essay The Jewish Parasite, Alex Bein argues that Nazi ideology captivated the German people through repeated use of words and concepts that eventually led to “belief in the reality of a fantasy.” Richard A. Koenigsberg, author of the seminal Hitler's Ideology, elaborated:
“In language, Bein explains, thoughts and conceptions are mirrored. Nazism crept into the flesh and blood of the masses by means of “single words, terms and phrases, and stock expressions” which, imposed upon the people a million times over in continuous reiteration, were “mechanically and unconsciously absorbed by them.” The presentation of Jews as corroding and poison parasites as vermin, bacteria and bacilli—everywhere infecting and striving to destroy the body of the German people— “paralyzed any internal resistance on the part of the masses.””
(Anti-Semetic Nazi propaganda)
A recent study suggests that disgust-oriented language can wield surprising power over our biases. Researchers Lene Aaroe, Michael Bang Petersen and Kevin Arceneaux asked two groups of participants to read a passage about a hospital employee coming in contact with bodily fluids. The passage given to one group, however, included an addition part in which the hospital employee thoroughly washes his hands. Anti-immigration sentiment dropped by 47 percent among this group, leading researchers to claim:
[Pathogen avoidance] plays a causal role in the formation of immigration attitudes and because hand washing is not logically connected with immigration attitudes, it ostensibly does so outside of one’s conscious awareness.
The findings imply that threats of actual infection need not be present in order for our sense of disgust to unconsciously affect how we see groups of people. Mere language can accomplish that.
Certain water beetles can escape from frogs after being consumed.
- A Japanese scientist shows that some beetles can wiggle out of frog's butts after being eaten whole.
- The research suggests the beetle can get out in as little as 7 minutes.
- Most of the beetles swallowed in the experiment survived with no complications after being excreted.
In what is perhaps one of the weirdest experiments ever that comes from the category of "why did anyone need to know this?" scientists have proven that the Regimbartia attenuata beetle can climb out of a frog's butt after being eaten.
The research was carried out by Kobe University ecologist Shinji Sugiura. His team found that the majority of beetles swallowed by black-spotted pond frogs (Pelophylax nigromaculatus) used in their experiment managed to escape about 6 hours after and were perfectly fine.
"Here, I report active escape of the aquatic beetle R. attenuata from the vents of five frog species via the digestive tract," writes Sugiura in a new paper, adding "although adult beetles were easily eaten by frogs, 90 percent of swallowed beetles were excreted within six hours after being eaten and, surprisingly, were still alive."
One bug even got out in as little as 7 minutes.
Sugiura also tried putting wax on the legs of some of the beetles, preventing them from moving. These ones were not able to make it out alive, taking from 38 to 150 hours to be digested.
Naturally, as anyone would upon encountering such a story, you're wondering where's the video. Thankfully, the scientists recorded the proceedings:
The Regimbartia attenuata beetle can be found in the tropics, especially as pests in fish hatcheries. It's not the only kind of creature that can survive being swallowed. A recent study showed that snake eels are able to burrow out of the stomachs of fish using their sharp tails, only to become stuck, die, and be mummified in the gut cavity. Scientists are calling the beetle's ability the first documented "active prey escape." Usually, such travelers through the digestive tract have particular adaptations that make it possible for them to withstand extreme pH and lack of oxygen. The researchers think the beetle's trick is in inducing the frog to open a so-called "vent" controlled by the sphincter muscle.
"Individuals were always excreted head first from the frog vent, suggesting that R. attenuata stimulates the hind gut, urging the frog to defecate," explains Sugiura.
For more information, check out the study published in Current Biology.
Are "humanized" pigs the future of medical research?
The U.S. Food and Drug Administration requires all new medicines to be tested in animals before use in people. Pigs make better medical research subjects than mice, because they are closer to humans in size, physiology and genetic makeup.
In recent years, our team at Iowa State University has found a way to make pigs an even closer stand-in for humans. We have successfully transferred components of the human immune system into pigs that lack a functional immune system. This breakthrough has the potential to accelerate medical research in many areas, including virus and vaccine research, as well as cancer and stem cell therapeutics.
Existing biomedical models
Severe Combined Immunodeficiency, or SCID, is a genetic condition that causes impaired development of the immune system. People can develop SCID, as dramatized in the 1976 movie “The Boy in the Plastic Bubble." Other animals can develop SCID, too, including mice.
Researchers in the 1980s recognized that SCID mice could be implanted with human immune cells for further study. Such mice are called “humanized" mice and have been optimized over the past 30 years to study many questions relevant to human health.
Mice are the most commonly used animal in biomedical research, but results from mice often do not translate well to human responses, thanks to differences in metabolism, size and divergent cell functions compared with people.
Nonhuman primates are also used for medical research and are certainly closer stand-ins for humans. But using them for this purpose raises numerous ethical considerations. With these concerns in mind, the National Institutes of Health retired most of its chimpanzees from biomedical research in 2013.
Alternative animal models are in demand.
Swine are a viable option for medical research because of their similarities to humans. And with their widespread commercial use, pigs are met with fewer ethical dilemmas than primates. Upwards of 100 million hogs are slaughtered each year for food in the U.S.
In 2012, groups at Iowa State University and Kansas State University, including Jack Dekkers, an expert in animal breeding and genetics, and Raymond Rowland, a specialist in animal diseases, serendipitously discovered a naturally occurring genetic mutation in pigs that caused SCID. We wondered if we could develop these pigs to create a new biomedical model.
Our group has worked for nearly a decade developing and optimizing SCID pigs for applications in biomedical research. In 2018, we achieved a twofold milestone when working with animal physiologist Jason Ross and his lab. Together we developed a more immunocompromised pig than the original SCID pig – and successfully humanized it, by transferring cultured human immune stem cells into the livers of developing piglets.
During early fetal development, immune cells develop within the liver, providing an opportunity to introduce human cells. We inject human immune stem cells into fetal pig livers using ultrasound imaging as a guide. As the pig fetus develops, the injected human immune stem cells begin to differentiate – or change into other kinds of cells – and spread through the pig's body. Once SCID piglets are born, we can detect human immune cells in their blood, liver, spleen and thymus gland. This humanization is what makes them so valuable for testing new medical treatments.
We have found that human ovarian tumors survive and grow in SCID pigs, giving us an opportunity to study ovarian cancer in a new way. Similarly, because human skin survives on SCID pigs, scientists may be able to develop new treatments for skin burns. Other research possibilities are numerous.
The ultraclean SCID pig biocontainment facility in Ames, Iowa. Adeline Boettcher, CC BY-SA
Pigs in a bubble
Since our pigs lack essential components of their immune system, they are extremely susceptible to infection and require special housing to help reduce exposure to pathogens.
SCID pigs are raised in bubble biocontainment facilities. Positive pressure rooms, which maintain a higher air pressure than the surrounding environment to keep pathogens out, are coupled with highly filtered air and water. All personnel are required to wear full personal protective equipment. We typically have anywhere from two to 15 SCID pigs and breeding animals at a given time. (Our breeding animals do not have SCID, but they are genetic carriers of the mutation, so their offspring may have SCID.)
As with any animal research, ethical considerations are always front and center. All our protocols are approved by Iowa State University's Institutional Animal Care and Use Committee and are in accordance with The National Institutes of Health's Guide for the Care and Use of Laboratory Animals.
Every day, twice a day, our pigs are checked by expert caretakers who monitor their health status and provide engagement. We have veterinarians on call. If any pigs fall ill, and drug or antibiotic intervention does not improve their condition, the animals are humanely euthanized.
Our goal is to continue optimizing our humanized SCID pigs so they can be more readily available for stem cell therapy testing, as well as research in other areas, including cancer. We hope the development of the SCID pig model will pave the way for advancements in therapeutic testing, with the long-term goal of improving human patient outcomes.
Adeline Boettcher earned her research-based Ph.D. working on the SCID project in 2019.
Satellite imagery can help better predict volcanic eruptions by monitoring changes in surface temperature near volcanoes.
- A recent study used data collected by NASA satellites to conduct a statistical analysis of surface temperatures near volcanoes that erupted from 2002 to 2019.
- The results showed that surface temperatures near volcanoes gradually increased in the months and years prior to eruptions.
- The method was able to detect potential eruptions that were not anticipated by other volcano monitoring methods, such as eruptions in Japan in 2014 and Chile in 2015.
How can modern technology help warn us of impending volcanic eruptions?
One promising answer may lie in satellite imagery. In a recent study published in Nature Geoscience, researchers used infrared data collected by NASA satellites to study the conditions near volcanoes in the months and years before they erupted.
The results revealed a pattern: Prior to eruptions, an unusually large amount of heat had been escaping through soil near volcanoes. This diffusion of subterranean heat — which is a byproduct of "large-scale thermal unrest" — could potentially represent a warning sign of future eruptions.
Conceptual model of large-scale thermal unrestCredit: Girona et al.
For the study, the researchers conducted a statistical analysis of changes in surface temperature near volcanoes, using data collected over 16.5 years by NASA's Terra and Aqua satellites. The results showed that eruptions tended to occur around the time when surface temperatures near the volcanoes peaked.
Eruptions were preceded by "subtle but significant long-term (years), large-scale (tens of square kilometres) increases in their radiant heat flux (up to ~1 °C in median radiant temperature)," the researchers wrote. After eruptions, surface temperatures reliably decreased, though the cool-down period took longer for bigger eruptions.
"Volcanoes can experience thermal unrest for several years before eruption," the researchers wrote. "This thermal unrest is dominated by a large-scale phenomenon operating over extensive areas of volcanic edifices, can be an early indicator of volcanic reactivation, can increase prior to different types of eruption and can be tracked through a statistical analysis of little-processed (that is, radiance or radiant temperature) satellite-based remote sensing data with high temporal resolution."
Temporal variations of target volcanoesCredit: Girona et al.
Although using satellites to monitor thermal unrest wouldn't enable scientists to make hyper-specific eruption predictions (like predicting the exact day), it could significantly improve prediction efforts. Seismologists and volcanologists currently use a range of techniques to forecast eruptions, including monitoring for gas emissions, ground deformation, and changes to nearby water channels, to name a few.
Still, none of these techniques have proven completely reliable, both because of the science and the practical barriers (e.g. funding) standing in the way of large-scale monitoring. In 2014, for example, Japan's Mount Ontake suddenly erupted, killing 63 people. It was the nation's deadliest eruption in nearly a century.
In the study, the researchers found that surface temperatures near Mount Ontake had been increasing in the two years prior to the eruption. To date, no other monitoring method has detected "well-defined" warning signs for the 2014 disaster, the researchers noted.
The researchers hope satellite-based infrared monitoring techniques, combined with existing methods, can improve prediction efforts for volcanic eruptions. Volcanic eruptions have killed about 2,000 people since 2000.
"Our findings can open new horizons to better constrain magma–hydrothermal interaction processes, especially when integrated with other datasets, allowing us to explore the thermal budget of volcanoes and anticipate eruptions that are very difficult to forecast through other geophysical/geochemical methods."