Why Do Humans Hate Immigrants? More Importantly, How Can We Get Over It?

It's always been our brains. 

Two groups were asked to lie. One had to speak the untruth; the other write it down. On the way out each participant was offered a cleaning product. As you might expect, the speakers chose mouthwash, while the scribes went for hand soap. 

Why do we confuse a moral transgression with a physical action? Neuroendocrinologist Robert Sapolsky believes humans are more easily tricked than we might believe. In this case he’d label it a case of co-optation more than confusion, though the latter does stem from the former. 

To understand this behavior we have to investigate the insular cortex. In Sapolsky’s latest book, Behave: The Biology of Humans at Our Best and Worst, he calls it an honorary part of our brain’s prefrontal cortex. The insula, for shorthand, is involved in consciousness and plays numerous roles: maintaining homeostasis, perception, cognitive functioning, motor control, and interpersonal experience. 

Among other functions, the insula plays an important role in processing emotions and helping decide what actions we take. Importantly, it often ‘talks’ with our amygdala, the region that helps process memories and emotions. The amygdala is also implicated in our fight-flight-freeze mechanism. When something is off it readies our body for action (or inaction). 

Most of the time we’re balanced. As homeostasis is the system that regulates our body temperature and hormonal concentrations, it makes sense that how we’re feeling physically is related to how we’re feeling emotionally. The two are inseparable. So if something makes us feel “off,” that we “feel” it and “think” it simultaneously is simply how our body and brain communicate. 

Now let’s think about one particular feeling. The insula plays a specific role in disgust. As Sapolsky told Big Think earlier this year, when you bite into rancid food or smell something putrid, a chain reaction occurs: you gag, become nauseous, and sometimes throw up. This is an evolutionary design, a “great way to not get poisoned.” As he writes in Behave,

The insula not only prompts the stomach to purge itself of toxic food; it prompts the stomach to purge the reality of a nightmarish event. The distance between the symbolic message and the meaning disappears. 

You’d expect every animal to purge toxins. It’s how animals avoid death. Purging a toxic thought is another thing entirely. Here’s where it gets more interesting. Humans are a “symbolic species,” Sapolsky says, which has led to “all sorts of interesting improvisations.” 

One of these improvisations is the concept of moral transgression. Sapolsky spent twenty-five years in the field studying baboons. When one does something bad to another, he doesn’t perform a ritual to ask for forgiveness, and he certainly doesn’t sit around for weeks mulling over his poor ethical decision.

Humans developed a different sensibility, one that involved the cooptation of the insular cortex. Or, as Sapolsky puts it, the part of our brain that controls our tongue is also responsible for our morals. This is apparent in the language we use when describing how we feel about a moral transgression: I feel sick to my stomach. It leaves a bad taste in my mouth. I need to wash my hands of having done that. 

Whether we’re physically or morally disgusted our insular cortex plays a role. This leads to another reality, one we’re witnessing on a daily basis. When someone else—say, an immigrant or person of another religious faith—dresses differently, eats different foods, or prays in a different manner, hello insula. We confuse “different" with “wrong.”

We like to think of ourselves as more evolved than the baboons Sapolsky spent countless hours gazing at. In many ways we are; evolution didn’t “give” us opposable thumbs for nothing. But what we call the unconscious plays a more important role than we often give it credit for. Consciousness is just the protruding tip of a very large iceberg. 

As Sapolsky puts it, in the fifty thousand years since we started becoming a symbolic species we haven’t evolved all that much. Nervous systems take time to mature. Evolutionary speaking, maybe we’re teens, though some still act as infants. They bad. We good. Sadly, this explains so much. 

Research matters. If you read the literature you know that why you think you’re entering a study and the actual reason are often worlds apart. If you knew exactly what was being studied your behavior would change. The explanation is often a cover for the details. 

Details such as the difference between sitting in a hard or soft chair. If you meet someone while sitting on an unforgiving substance you’re more likely to label them as “hard.” You’ll have less of a connection. Same goes for hot versus chilly mugs: Wow, is that person cold. No warmth to them. Research also shows that you connect with someone better if they mimic your pantomimes. Fold your arms during conversation with a stranger. If they follow suit, you’re more likely to trust them. 

The insula protects us against life-threatening dangers. With moral transgressions the dangers don't actually need to threaten our lives for our insula to jump into overdrive. Sapolsky points to a study in which subjects did or did not read an article about airborne bacteria. Both groups then read a history article calling the United States an organism.

Those who read about scary bacteria before thinking about the United States as an organism were then more likely to express negative view about immigration.

We’ve long been locked in this Us-Them mentality. It’s an integral part of our biological inheritance. And it’s not going to go away, regardless of how highly we think of ourselves. Or maybe it will, during our next upgrade fifty thousands years from now. Geological and neurological time laugh at our timelines, though. We will always relates to Us’s and take stock of Them’s, regardless of how much the Us is dangerous and the Them is supportive. It’s called politics, and we have our own nightmarish events to contend with. 

This is the reason the Joe Arpaio pardon has brought about so many comments of disgust and disbelief, why Arpaio’s rants against immigrants received so many affirmative cheers. Us and Them is not relegated to skin color or ethnicity. It’s a constant dance. I recently read an article by a woman who didn’t know her husband was a climate change skeptic until months into their marriage, even though she was working as a climate engineer. They are divorced now. How quickly an Us becomes a Them. 

And yet. This very system is responsible for why we feel someone else’s pain. In his book (and this Big Think video) Sapolsky talks about the “love hormone,” oxytocin, which was treated like a miracle for its role in making us bond and cuddle. True, with Us’s. The same hormone makes us more likely to turn our nose in disgust at a Them. This is one of many cases of chemistry interacting with environment. Or, as he writes,

Biologically, intense love and intense hate aren’t opposites. The opposite of each is indifference.

What matters is action. As he reiterates throughout Behave, feeling empathy does not necessarily translate into acting bravely. It can be a catalyst for doing so, yet we often confuse feeling and action, which in a selfish twist makes us feel better without our having really done anything. We’ve reached a point where such selfishness isn’t sustainable. Every day we see the consequences. 

The insular cortex is, as Sapolsky writes, an honorary part of the frontal cortex. And that is where transformative actions are possible:

The frontal cortex makes you do the harder thing when it’s the right thing to do. 

The insula in part led to moral transgressions; now we must co-opt it again. As Sapolsky concludes, do the hard thing enough times and it’s no longer the hard thing. It’s amazing how much easier things could be right now, if only we realized the Them's are a lot more like Us than we think.


Derek is the author of Whole Motion: Training Your Brain and Body For Optimal Health. Based in Los Angeles he is working on a new book about spiritual consumerism. Stay in touch on Facebook and Twitter.

Big Think
Sponsored by Lumina Foundation

Upvote/downvote each of the videos below!

As you vote, keep in mind that we are looking for a winner with the most engaging social venture pitch - an idea you would want to invest in.

Keep reading Show less

Essential financial life skills for 21st-century Americans

Having these financial life skills can help you navigate challenging economic environments.

Photo by Jp Valery on Unsplash
Personal Growth
  • Americans are swimming in increasingly higher amounts of debt, even the upper middle class.
  • For many, this burden can be alleviated by becoming familiar with some straightforward financial concepts.
  • Here's some essential financial life skills needed to ensure your economic wellbeing.
Keep reading Show less

How to flirt: 7 tips backed by science

When it comes to flirting, love meters have nothing on these researchers' findings.

(Photo from Wikimedia)
Sex & Relationships
  • Flirting is an important part of life. It can be a fun, adventurous way to meet others and develop intimate relationships.
  • Many people find flirting to be an anxiety-ridden experience, but science can help us discover principles to be more relaxed while flirting.
  • Smiling and eye contact are proven winners, while pick-up lines are a flirty fallacy.
Keep reading Show less

New fossils suggest human ancestors evolved in Europe, not Africa

Experts argue the jaws of an ancient European ape reveal a key human ancestor.

Surprising Science
  • The jaw bones of an 8-million-year-old ape were discovered at Nikiti, Greece, in the '90s.
  • Researchers speculate it could be a previously unknown species and one of humanity's earliest evolutionary ancestors.
  • These fossils may change how we view the evolution of our species.

Homo sapiens have been on earth for 200,000 years — give or take a few ten-thousand-year stretches. Much of that time is shrouded in the fog of prehistory. What we do know has been pieced together by deciphering the fossil record through the principles of evolutionary theory. Yet new discoveries contain the potential to refashion that knowledge and lead scientists to new, previously unconsidered conclusions.

A set of 8-million-year-old teeth may have done just that. Researchers recently inspected the upper and lower jaw of an ancient European ape. Their conclusions suggest that humanity's forebearers may have arisen in Europe before migrating to Africa, potentially upending a scientific consensus that has stood since Darwin's day.

Rethinking humanity's origin story

The frontispiece of Thomas Huxley's Evidence as to Man's Place in Nature (1863) sketched by natural history artist Benjamin Waterhouse Hawkins. (Photo: Wikimedia Commons)

As reported in New Scientist, the 8- to 9-million-year-old hominin jaw bones were found at Nikiti, northern Greece, in the '90s. Scientists originally pegged the chompers as belonging to a member of Ouranopithecus, an genus of extinct Eurasian ape.

David Begun, an anthropologist at the University of Toronto, and his team recently reexamined the jaw bones. They argue that the original identification was incorrect. Based on the fossil's hominin-like canines and premolar roots, they identify that the ape belongs to a previously unknown proto-hominin.

The researchers hypothesize that these proto-hominins were the evolutionary ancestors of another European great ape Graecopithecus, which the same team tentatively identified as an early hominin in 2017. Graecopithecus lived in south-east Europe 7.2 million years ago. If the premise is correct, these hominins would have migrated to Africa 7 million years ago, after undergoing much of their evolutionary development in Europe.

Begun points out that south-east Europe was once occupied by the ancestors of animals like the giraffe and rhino, too. "It's widely agreed that this was the found fauna of most of what we see in Africa today," he told New Scientists. "If the antelopes and giraffes could get into Africa 7 million years ago, why not the apes?"

He recently outlined this idea at a conference of the American Association of Physical Anthropologists.

It's worth noting that Begun has made similar hypotheses before. Writing for the Journal of Human Evolution in 2002, Begun and Elmar Heizmann of the Natural history Museum of Stuttgart discussed a great ape fossil found in Germany that they argued could be the ancestor (broadly speaking) of all living great apes and humans.

"Found in Germany 20 years ago, this specimen is about 16.5 million years old, some 1.5 million years older than similar species from East Africa," Begun said in a statement then. "It suggests that the great ape and human lineage first appeared in Eurasia and not Africa."

Migrating out of Africa

In the Descent of Man, Charles Darwin proposed that hominins descended out of Africa. Considering the relatively few fossils available at the time, it is a testament to Darwin's astuteness that his hypothesis remains the leading theory.

Since Darwin's time, we have unearthed many more fossils and discovered new evidence in genetics. As such, our African-origin story has undergone many updates and revisions since 1871. Today, it has splintered into two theories: the "out of Africa" theory and the "multi-regional" theory.

The out of Africa theory suggests that the cradle of all humanity was Africa. Homo sapiens evolved exclusively and recently on that continent. At some point in prehistory, our ancestors migrated from Africa to Eurasia and replaced other subspecies of the genus Homo, such as Neanderthals. This is the dominant theory among scientists, and current evidence seems to support it best — though, say that in some circles and be prepared for a late-night debate that goes well past last call.

The multi-regional theory suggests that humans evolved in parallel across various regions. According to this model, the hominins Homo erectus left Africa to settle across Eurasia and (maybe) Australia. These disparate populations eventually evolved into modern humans thanks to a helping dollop of gene flow.

Of course, there are the broad strokes of very nuanced models, and we're leaving a lot of discussion out. There is, for example, a debate as to whether African Homo erectus fossils should be considered alongside Asian ones or should be labeled as a different subspecies, Homo ergaster.

Proponents of the out-of-Africa model aren't sure whether non-African humans descended from a single migration out of Africa or at least two major waves of migration followed by a lot of interbreeding.

Did we head east or south of Eden?

Not all anthropologists agree with Begun and his team's conclusions. As noted by New Scientist, it is possible that the Nikiti ape is not related to hominins at all. It may have evolved similar features independently, developing teeth to eat similar foods or chew in a similar manner as early hominins.

Ultimately, Nikiti ape alone doesn't offer enough evidence to upend the out of Africa model, which is supported by a more robust fossil record and DNA evidence. But additional evidence may be uncovered to lend further credence to Begun's hypothesis or lead us to yet unconsidered ideas about humanity's evolution.