The climate your ancestors came from shaped your nose
Knowing the details of genetic variance may help improve personalized medicine.
I have a schnoz just below Cyrano scale. My friend calls it a Roman senator's beak, while my wife claims it's more like a ski slope. I usually interject something like lions have strong noses or that the Romans once controlled most of the known world, which is met with eye rolls or smirks. When people try to guess my ethnicity, they usually say either Jewish or Italian.
Though I'm a mutt, the largest portion of my roots come from Southern Italy, mostly Calabria, Naples, and Sicily. In everyday culture, we consider certain physical attributes as revealing our nationality or ethnicity, such as my Italian-American honker. But is this supported by science?
Well, let's consider the nose. Whether or not there is an evolutionary basis for the wide variety in shape and size among humans has been of much debate among scientists for some time. The nose and surrounding sinuses have a distinct purpose—to warm, moisten, and filter the air we breathe. For this reason, scientists have thought that differences in the size and shape may have something to do with the climate a people developed in.
Now, a recent study published in the journal PLOS Genetics in 2017 lends valuable evidence to the notion. Nostril size varies remarkably from one population to the next. Those with wider nostrils according to this study, developed in warmer, wetter climates, while those with narrower nostrils developed in colder, dryer ones. Narrow nostrils are beneficial in cold climates because they can more effectively trap and heat the air before it's inhaled, and the opposite for wider nostrils in warmer climates. This is thought to be a trait passed down through natural selection.
People from colder, drier climates tend to have smaller nostrils.
A team of scientists from Ireland, Belgium, and the US conducted the study, led by experts at Penn State University. Arslan Zaidi is a postdoctoral researcher and co-author on the study, which included 476 participants. Each had a 3D image taken of their face. Researchers took several nose-related traits into consideration: protrusion, height, and width, and two non-nose related: skin pigmentation, and the person's height.
Participants were of east Asian, south Asian, northern European, or west African descent. Of the total, 140 women, about 40 from each ethnic or racial group, had their nose measurements examined. Dr. Zaidi said, “We selected these to maximize the distance across populations." Each were assigned to a particular temperature and humidity point system, due to where their ancestors originated.
The researchers put that data on a scale, and results became clear. The size of participants' nostrils were directly associated with the temperature and humidity ranges of particular regions. In the future, Zaidi and colleagues hope to add more racial and ethnic groups to their research. Of the five attributes, only nostril width and skin pigmentation showed differences greater than chance, attributing these to genetic mutation and natural selection, instead.
The size and shape of one's nose is passed down from one generation to the next.
The correlation between climate and nostril size was most prominent for Northern Europeans. Skin pigment and climate correlate even more strongly, however. These findings can be corroborated by previous research, which found that the nasal slits in skulls were narrower in peoples who came from northern regions.
The shape of one's nose has also been proven to be inheritable. Unrelated people who had a similar nose shape were found to have comparable genes. The fact that skin pigment had a stronger correlation may say something about other factors, such as what cultures value in terms of aesthetics and attraction.
These results may improve personalized medicine. Knowing the details surrounding genetic variance can help gauge one's risk to certain diseases. “We know there are variable risks of respiratory diseases across different populations in the U.S.," Dr. Zaidi said. “Can we find an explanation for that in morphology?"
It's important to note that the vast majority of human genes are common ones. There's less than 15% of genetic variation in our species, which is attributable to our developing in different regions, according to Dr. Zaidi. “People are more similar than they are different," he said. “What this research does is offer people a view of why we're different. There's an evolutionary history to it that, I think, kind of demystifies the concept of race."
To learn more about how evolution has shaped your body, click here:
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The idea of 'absolute time' is an illusion. Physics and subjective experience reveal why.
- Since Einstein posited his theory of general relativity, we've understood that gravity has the power to warp space and time.
- This "time dilation" effect occurs even at small levels.
- Outside of physics, we experience distortions in how we perceive time — sometimes to a startling extent.
Physics without time<p>In his book "The Order of Time," Italian theoretical physicist Carlo Rovelli suggests that our perception of time — our sense that time is forever flowing forward — could be a highly subjective projection. After all, when you look at reality on the smallest scale (using equations of quantum gravity, at least), time vanishes.</p><p style="margin-left: 20px;">"If I observe the microscopic state of things," writes Rovelli, "then the difference between past and future vanishes … in the elementary grammar of things, there is no distinction between 'cause' and 'effect.'"</p><p>So, why do we perceive time as flowing <em>forward</em>? Rovelli notes that, although time disappears on extremely small scales, we still obviously perceive events occur sequentially in reality. In other words, we observe entropy: Order changing into disorder; an egg cracking and getting scrambled.</p><p>Rovelli says key aspects of time are described by the second law of thermodynamics, which states that heat always passes from hot to cold. This is a one-way street. For example, an ice cube melts into a hot cup of tea, never the reverse. Rovelli suggests a similar phenomenon might explain why we're only able to perceive the past and not the future.</p><p style="margin-left: 20px;">"Any time the future is definitely distinguishable from the past, there is something like heat involved," Rovelli wrote for the <a href="https://www.ft.com/content/ce6ef7b8-429a-11e8-93cf-67ac3a6482fd" target="_blank"><em>Financial Times</em></a>. "Thermodynamics traces the direction of time to something called the 'low entropy of the past', a still mysterious phenomenon on which discussions rage."</p>
The strange subjectivity of time<p>Time moves differently atop a mountain than it does on a beach. But you don't need to travel any distance at all to experience strange distortions in your perception of time. In moments of life-or-death fear, for example, your brain would release large amounts of adrenaline, which would speed up your internal clock, causing you to perceive the outside world as moving slowly.<br></p><p>Another common distortion occurs when we focus our attention in particular ways.</p><p style="margin-left: 20px;">"If you're thinking about how time is <em>currently</em> passing by, the biggest factor influencing your time perception is attention," Aaron Sackett, associate professor of marketing at the University of St. Thomas, told <em><a href="https://gizmodo.com/why-does-time-slow-down-and-speed-up-1840133782" target="_blank">Gizmodo</a></em>.<em> "</em>The more attention you give to the passage of time, the slower it tends to go. As you become distracted from time's passing—perhaps by something interesting happening nearby, or a good daydreaming session—you're more likely to lose track of time, giving you the feeling that it's slipping by more quickly than before. "Time flies when you're having fun," they say, but really, it's more like "time flies when you're thinking about other things." That's why time will also often fly by when you're definitely <em>not</em> having fun—like when you're having a heated argument or are terrified about an upcoming presentation."</p><p>One of the most mysterious ways people experience time-perception distortions is through psychedelic drugs. In an interview with <a href="https://www.theguardian.com/books/2018/apr/14/carlo-rovelli-exploding-commonsense-notions-order-of-time-interview" target="_blank"><em>The Guardian</em></a>, Rovelli described a time he experimented with LSD.</p><p style="margin-left: 20px;">"It was an extraordinarily strong experience that touched me also intellectually," he said. "Among the strange phenomena was the sense of time stopping. Things were happening in my mind but the clock was not going ahead; the flow of time was not passing any more. It was a total subversion of the structure of reality."<br></p><p>It seems few scientists or philosophers believe time is completely an illusion.</p><p style="margin-left: 20px;">"What we call <em>time</em> is a rich, stratified concept; it has many layers," Rovelli told <em><a href="https://physicstoday.scitation.org/do/10.1063/PT.6.4.20190219a/full/" target="_blank">Physics Today</a>.</em> "Some of time's layers apply only at limited scales within limited domains. This does not make them illusions."</p>What <em>is</em> an illusion is the idea that time flows at an absolute rate. The river of time might be flowing forever forward, but it moves at different speeds, between people, and even within your own mind.
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Controversial physics theory says reality around us behaves like a computer neural network.
- Physicist proposes that the universe behaves like an artificial neural network.
- The scientist's new paper seeks to reconcile classical physics and quantum mechanics.
- The theory claims that natural selection produces both atoms and "observers".
Vanchurin interview:<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="539759cbfd8fcd5b6ebf14a3b597b3f9"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/bmyRy2-UhEE?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
Vanchurin on “Hidden Phenomena”:<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="18886ffd5e5840bb19d4494212f88d82"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/2NDVdNwsHCo?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>Vitaly Vanchurin speaking at the 6th International FQXi Conference, "Mind Matters: Intelligence and Agency in the Physical World." The Foundational Questions...
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