Nature’s Calling: How Long Should Humans Live?
Tyler Volk: Our closest primate relatives are the chimpanzees and gorillas, with the chimpanzees being closer to us genetically. They’re natural life spans are approximately half of ours. And that’s of some interest because the chimpanzees are a bit smaller than use in body mass and the gorillas are larger than us in body mass. We can’t know for sure the lifespan of the last common ancestor of humans and chimpanzees, but there would be some – you might guess that it would be half of what our current lifespan is.
Question: This is the natural lifespan?
Tyler Volk: Let’s make a distinction that we’re not talking about the infants dying – small children dying of diseases or death by predator, but the natural lifespan in normal, almost perfect circumstances. So looks throughout history, there’s always been people who have made it to age 80 or so, or longer, even though the average life expectance at birth, given all factors, given diseases, predators, and then the diseases of aging and senescence, even those have been more prevalent, the natural lifespan has been approximately the same as it is today. The maximum – the natural maximum lifespan, which is different from life expectancy at birth which can vary even in different countries today. Russia right now has a relatively low life expectancy, people in Africa have a relatively low life expectancy, Japan has the highest life expectancy of any nation now. So, there’s variations, but take those individuals into relatively equal healthy environments and they’re all going to live close to the same age.
Question: And this natural life expectancy has not gone up?
Tyler Volk: Right. The natural life expectancy has not gone up very much. However, since the diseases, some of the diseases that modern medicine is tackling, such as heart disease and cancer, become more and more the diseases that we are dying from in elderly age, we can be expected to live longer without trying to genetically go in and manipulate our metabolisms in some ways. There’s a lot of work being done on what is called caloric restriction.
There’s a lot of research being done on what is called caloric restriction. Animals that are given reduced calorie diets, and yet have the essential nutrients that they need, live longer. We haven’t been able to do the experiments on human beings yet. There are people out there attempting to do this by themselves. You can get books and join organizations to try to enhance or help you – how you can make recipes that satisfy your hunger and have caloric restriction.
I’m saying this to show that there are probably going to be ways that science is going to understand this natural demise, this metabolic demise of our repair mechanisms that set up our natural lifespan that has kept it pretty constant for a long time. And we’re probably going to bring that forward. We’re going to live longer lives I really think. I don’t know if it’s right around the corner, that’s hard to judge. You’ve had people on your show that are saying what they think it’s going to be. But just from reading the literature, it’s clear that these kinds of advances are going to happen.
Question: Why do lifespans vary across species?
Tyler Volk: I find it really fascinating to consider why certain species of mammals live longer than other species of mammals. For example, we live longer than dogs, dogs live longer than mice. Often there’s a tendency, or trend, that the large creatures live longer. But you might try to say, from an evolutionary viewpoint, that it would serve creatures well to live for a long time. They can reproduce more, let’s say if they live for longer, and therefore can pass on their genes for even a longer period of time. But we know that there’s a large variation in when creatures senesce and what the average lifespan is. And it turns out, there’s two ways of looking at this. One is to go down deep into the organism and ask, why are the cellular repair mechanisms breaking down when they do; a couple years in the case of some small mammals. For us it’s many decades, 70, 80, 90 years. But the other way to look at it is that these cellular repair mechanisms themselves must be subject to evolution. We know that these repair mechanisms vary among creatures.
It’s been shown that birds, for example, have better cellular repair mechanisms than mammals do. The current reasoning has to do with the ecological niche that a certain creature lives within as a member of its species. And if that niche allows the possibility for many of the individuals to live long lives, then it has been worthwhile for the evolutionary process to build in better repair mechanisms for its cells to allow it to live longer. So, if I go back to the example of birds, the phrase that’s sometimes used in the technical literature for birds and why the birds live so much longer than the mammals of the same body mass is the phrase, “fly now, die later.” And the idea being that birds in the trees and in flying have very good predator escape mechanisms that make it worthwhile for the birds to have cellular repair mechanisms inside their bodies that allow this longevity for a certain body mass to occur.
And what I find fascinating here is that there is a tuning of the creature’s niche, or environmental lifestyle and the possibilities that that lifestyle has for longevity and the very internal, deep internal, cellular repair mechanisms. The enzyme repair mechanisms issues about oxidative stress that either facilitate that longevity or cut the life short. One particular example I think is very telling is the case of the several species of the Pacific Salmon that live in the Northwest United States, Canada, and in Alaska. These salmon are born in upstream fresh water streams, or rivers. Very quickly, they go down to the saltwater oceans so they have a transition from fresh water to saltwater ocean. They live in the ocean for typically two to three years, depending on the species. They find their way back through a process somewhat mysterious, but maybe having to do with the water chemistry of their birth stream. They find they’re way back to their birth stream and at that point, the males and the females undergo some physiological changes. Their bodies turn more red, they bolt out – the males, the jaws get very bulked out. And if you look at what’s happening hormonally in them, it’s like they’re on an incredible dose of steroids. They’re revved up for this upstream swim that we see dramatic pictures of where they’re swimming these rapids and can they hop this dam or not, or do they have ladders to go up.
They go upstream and the males and females mate. The females lay the eggs in these little depressions in the sediments, and then the males and females all die. They do not go back downstream to say, live another year and come back upstream. And you might think that what’s happening is a real waste of these salmon. It’s been shown that they add some nutrients to the stream water, but they’re not dying to add nutrients to the upstream waters, they’re dying because what’s happened to their bodies has put such stress on their bodies that they’ve done this incredible swim and put all their efforts into getting to a place to mate and into mating. And this is a wonderful example of how it’s important for these organisms to remain healthy up until sex, up until successful sex and reproduction and then it’s possible to die. Senecessence is, it’s possible just after sex. If there were senecessence before sex, that creature is out of the evolutionary game, obviously. But you could have death following right on the heels of sex and in the case of the salmon, this has occurred in evolution. So, we can see here that there is a tuning between death and when senecessence that happens and the ecological, or environmental, circumstances that have resulted in various adaptations in the case of Pacific Salmon. A really dramatic case.
Mammals, including humans, have natural lifespans that have remained about the same through each species’ existence. What are these figures, and why do they vary so greatly across species?
Join Radiolab's Latif Nasser at 1pm ET on Monday as he chats with Malcolm Gladwell live on Big Think.
The Labour Economics study suggests two potential reasons for the increase: corruption and increased capacity.
Cool hand rebuke<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQyMTIyNy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NjY1NTYyOH0.0MCPKN3If94mYCNf3mMNrnTvJXjXN_bKLhgk9203EXk/img.jpg?width=917&coordinates=0%2C0%2C0%2C0&height=453" id="1627b" class="rm-shortcode" data-rm-shortcode-id="6d76421ba1ea0de4b09956b97e80c384" data-rm-shortcode-name="rebelmouse-image" />
A chart showing prison population rates (per 100,000 people) in 2018. The United States has the highest rate of incarceration in the world.
Who profits with for-profit prisons?<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="97ac37e6c7f6f22ec130ea2d56871701"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/dB78NV2WpWc?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span><p>The Labour Economics study suggests that privately-run prisons do convicts a few favors at the moment of sentencing. However, proponents of private prisons often point to other benefits when making their case. Specifically, they argue that private prisons reduce operating costs, stimulate innovation in the correctional system, and reduce recidivism—the rate at which released prisoners are rearrested and return to prison.</p><p>In regard to recidivism, the research is mixed. <a href="https://journals.sagepub.com/doi/abs/10.1177/0011128799045001002" target="_blank">One study</a> compared roughly 400 former prisoners from Florida, 200 released from private prisons and 200 from state-run facilities. It found the private-prison cohort maintained lower rates of recidivism. However, <a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1745-9133.2005.00006.x" target="_blank" rel="noopener noreferrer">another Florida study</a> found no significant rate differences. And two other studies—one from <a href="https://journals.sagepub.com/doi/abs/10.1177/0011128799045001002" target="_blank" rel="noopener noreferrer">Oklahoma</a> and another out of <a href="https://journals.sagepub.com/doi/abs/10.1177/0734016813478823" target="_blank" rel="noopener noreferrer">Minnesota</a>, both comparing much larger cohorts than the first Florida study— found that prisoners leaving private prisons had a greater risk of recidivism.</p><p>The research is also inconclusive regarding cost savings. <a href="https://www.hamiltonproject.org/assets/files/economics_of_private_prisons.pdf" target="_blank" rel="noopener noreferrer">A Hamilton Project analysis</a> noted that such comparisons are difficult because private prisons, like all private companies, are not required to release operational details. In comparing what studies were available, the authors estimate the costs to be comparable and that "in practice the primary mechanism for cost saving in private prisons is lower salaries for correctional officers"—about $7,000 less than their public peers. They add that competition-driven innovation is lacking as the three largest firms control nearly the entire market.</p><p>"We aren't saying private prisons are bad," Galinato said. "But states need to be careful with them. If your state has previous and regular issues with corruption, I wouldn't be surprised to see laws being more skewed to give longer sentences, for example. If the goal is to reduce the number of incarcerated individuals, increasing the number of private prisons may not be the way to go."</p>
What exactly does "questions are the new answers" mean?
- Traditionally, intelligence has been viewed as having all the answers. When it comes to being innovative and forward-thinking, it turns out that being able to ask the right questions is an equally valuable skill.
- The difference between the right and wrong questions is not simply in the level of difficulty. In this video, geobiologist Hope Jahren, journalist Warren Berger, experimental philosopher Jonathon Keats, and investor Tim Ferriss discuss the power of creativity and the merit in asking naive and even "dumb" questions.
- "Very often the dumb question that is sitting right there that no one seems to be asking is the smartest question you can ask," Ferriss says, adding that "not only is it the smartest, most incisive, but if you want to ask it and you're reasonably smart, I guarantee you there are other people who want to ask it but are just embarrassed to do so."
A vertical map might better represent a world dominated by China and determined by shipping routes across the iceless Arctic.
- Europe has dominated cartography for so long that its central place on the world map seems normal.
- However, as the economic centre of gravity shifts east and the climate warms up, tomorrow's map may be very different.
- Focusing on both China and Arctic shipping lanes, this vertical representation could be the world map of the future.
The world, but not as we know it<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMDU1Nzg1NS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNTkwMjIyNn0.qmQfwUdjQka8JX6q4KGANagleiuucpWay5ytMenZxUU/img.jpg?width=980" id="b95e4" class="rm-shortcode" data-rm-shortcode-id="ac088ec55c0585a93a9a310faab9a4c7" data-rm-shortcode-name="rebelmouse-image" />
A Chinese 'vertical world map,' showing the world in a different perspective from the one we're used to.
Image: Prior Probability<p>Europe is tucked away in a corner, an appendage of Asia dwarfed by neighboring Africa. North America is stood on its head, facing the rest of the world from the top of the map — cut off from South America, which cuts a solitary figure at the bottom. Africa is justifiably huge, but equally eccentric. </p><p>The eye scouts elsewhere for a place to land: not the Indian Ocean, which dominates the middle of the map, but some terra firma. Antarctica and Australia are too small, mere stepping stones for the land mass of Asia. Ultimately our gaze is drawn toward China, the lynchpin of this unfamiliar world. </p><p>Managing to leave both poles intact, this "vertical" world map is about as far away as you can get from the classic Mercator projection – which slices up both, giving center stage to a puffed-up Europe. Perhaps this new map will become more familiar soon: It may do more justice to the world of the near future, dominated by China and determined by shipping routes across the iceless Arctic. <br></p>
China's 'ten-dash line'<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMDU1Nzg1Ni9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1NTI4MzQyNn0.sBe0oFTif4Jef1vWh1kAnUylU_QMPXT5xQjm-5aA3sA/img.jpg?width=980" id="a3b81" class="rm-shortcode" data-rm-shortcode-id="80fc6e4f5c9c1c978f698be2c8de5484" data-rm-shortcode-name="rebelmouse-image" />
'China without any part left out': includes Taiwan and the islands and atolls in the South China Sea, surrounded by a ten-dash line
Image: Global Times<p>While there's no indication that this map represents the Chinese government's "official" worldview, it is no secret that China has a thing with maps – and more specifically, the country's representation on them. </p><p>In China, the country's current economic success is seen as a redress of the unequal treatment meted out by western superpowers in the 19th century. China's world dominance is a return to a more natural state of world affairs, many feel. Cartographic rectifications are a symbolically significant corollary of that sentiment.</p><p><a href="https://www.citylab.com/equity/2015/12/china-cracks-down-on-politcally-incorrect-maps/421032/" target="_blank">Fines are regularly imposed</a> on companies – domestic and foreign – that fail to represent China to the fullest extent of its external borders, disputed though they may be by others (e.g. India, Taiwan and any of the countries with claims overlapping China's in the South China Sea). But the People's Republic's cartographic obsession doesn't end at China's territory itself. It also includes the country's position on the world map. <br></p>
The Kingdom at the Middle of the World<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMDU1Nzg2MS9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyOTkwODEzMX0.SGrAZBH6iJVggFYSaIahzv9GvfEh17y1SwUNINbVicQ/img.jpg?width=980" id="1774c" class="rm-shortcode" data-rm-shortcode-id="99790d80a909d17a948f7c5d463d7d98" data-rm-shortcode-name="rebelmouse-image" />
Early Japanese color copy of Ricci's world map
Image: public domain<p>China's name for itself is <em>Zhōngguó</em>, which means 'Central State' or 'Middle Kingdom', reflecting its ancient self-image as the civilized center (<em>Huá</em>) of the world, with wild tribes (<em>Yí</em>) at the edge. That view is not unique to China. Vietnam, for example, at certain times also styled itself as the "central state" (<em>Trung Quóc</em>) – considering the Chinese in turn as the uncouth outsiders.</p><p>It may be surprising to recall, but Europeans themselves once considered their own continent a relative backwater, viewing Jerusalem as the true center of the world. That changed with the Age of Discovery, which placed Europe at the center of an ever-expanding world. Maps reflected that worldview, and largely continue to do so. That's why today's standard world map still has Europe at its center – with China off toward the periphery on the map's right-hand side. </p><p>The most notable feature of the very first major modern world map produced in China, the <em>Kunyu Wanguo Quantu</em> (1602), is that it places China firmly at the center of the world. Produced for the Chinese emperor by Jesuit missionary Matteo Ricci, it was the first map ever to combine that perspective with modern western knowledge: it was the first Chinese map to show the Americas, for instance. </p><p>That representation may not have taken off elsewhere, but it will be instantly recognizable to Chinese students, as it's the standard format for world maps in China's schools today.<br></p>
America on its head<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yMDU1Nzg2My9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYwMzQ5NTc0MH0.EqadI2Yp-2dPwi3VccFZelIDK4V9t0ZOfTfHjdB6wVw/img.jpg?width=980" id="97104" class="rm-shortcode" data-rm-shortcode-id="2b66e8de389b3d736bc28e019e445cd0" data-rm-shortcode-name="rebelmouse-image" />
Upside down you turn me: North America on its head, in Chinese characters
Image: Prior Probability<p>For those used to "classic" Eurocentric world maps, Europe's marginalization may come across as a bit of an upset. America's new position on the horizontal Chinese world map is less jarring: It merely moves from the left- to the right-hand side of the picture. But then there's this vertical world map, which deals a similar blow to the American land mass: divided in two and pushed to the upper and lower edges of the map.</p><p>Unfamiliar? Sure. Shocking? Perhaps. Wrong? Not really. First off, no world map is totally right, since it's mathematically impossible to transfer the surface of a three-dimensional object onto a flat surface without some distortion. And since the world is a globe, where you center that map is a matter of purely subjective choice.<br></p><p>Those choices have historical reasons. Mercator's map was not specifically designed to put an inflated Europe at the center of the world. That was just a side effect; its main purpose was to aid shipping: Straight lines on the map correspond to straight lines sailed on the seas.</p>
By 2050, a completely melted Arctic could enable the Transpolar Passage, shortening trade routes between Asia and Europe and boosting business for Alaskan ports like Nome and Dutch Harbor.
Image: The Maritime Executive<p>The vertical world map, showing the relative proximity of China (and the rest of Asia) to Europe and (even the East Coast of) North America, has a similarly maritime <em>raison d'être</em>, or it will have by mid-century. <a href="https://www.maritime-executive.com/editorials/the-arctic-shipping-route-no-one-s-talking-about" target="_blank" rel="noopener noreferrer">Experts project</a> that by 2050 (if not sooner), the Arctic will be sufficiently ice-free to enable the so-called Transpolar Passage, i.e. shipping straight across the North Pole. </p><p>That would shave more than three weeks off a traditional sea voyage between Europe and Asia, via the Suez Canal – and even be significantly faster than other northern alternatives like the Northwest Passage (via Canada) or the Northern Sea Route (hugging the Siberian coast). Since ships would not need to go through locks or pass over shallow waters, it would also remove current restrictions on tonnage per ship. <br></p><p>The only country seriously preparing for such a future: China. None of the other Arctic powers is giving the Transpolar route any strategic thought. On the other hand, China's Arctic Policy document, released in January 2018, already matter-of-factly refers to the Transpolar route as the 'Central Passage' – one of several 'Polar Silk Roads' that China seems to want to develop. And they already have the world map to go with it.</p>
A large-scale study from King's College London explores the link between genetics and sun-seeking behaviors.
- There are a number of physical and mental health benefits to sun exposure, such as boosted vitamin D and serotonin levels and stronger bones.
- Addictions are multi-step conditions that, by definition, require exposure to the addictive agent and have also been proven to have a genetic factor. Countless people are exposed to addictive things, but not all become addicted. This is because of the genetic component of addiction.
- This large-scale study explores the link between sun-seeking behaviors and the genetic markers for addiction.
The benefits of sunlight<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQyMjI1Ni9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNzk0NDUxNH0.lbYbZidJkNXPUcWM6m8cucuzAFOANkqPaIVfJdqkJ4Q/img.jpg?width=1245&coordinates=0%2C52%2C0%2C52&height=700" id="d5fcd" class="rm-shortcode" data-rm-shortcode-id="f44fcc9a31393c8102803eb50d01a19a" data-rm-shortcode-name="rebelmouse-image" alt="woman sitting on dock in the sunlight" />
The mental and physical health benefits of sunlight have been heavily researched.
Credit: eldar nurkovic on Shutterstock<p>The benefits of sunlight have been widely discussed for many years. In fact, there are a number of physical and mental health benefits to sun exposure.</p><p><strong>Sunshine (and the lack of) impacts your hormone levels. </strong></p><p>Sunlight (and alternatively, the lack of sunlight) triggers the release of certain hormones in your brain. Exposure to sunlight is thought to increase serotonin, which is associated with boosting your mood and helping you feel calm and focused. </p><p>Alternatively, dark lighting triggers melatonin, a hormone that is helpful in allowing you to rest and fall asleep. Without enough sunlight, your serotonin levels can dip - and low serotonin levels have been associated with a higher risk of major depression with seasonal pattern (formerly known as seasonal affective disorder).</p><p><strong>Sunlight can build strong bones. </strong></p><p>Exposure to the ultraviolet-B radiation in the sun's rays can interact with your skin, causing it to create vitamin D. <a href="https://www.nhs.uk/conditions/vitamins-and-minerals/vitamin-d/" target="_blank" rel="noopener noreferrer">According to NHS</a>, vitamin D helps regulate the amount of calcium and phosphate in the body. A lack of vitamin D can lead to bone deformities or bone pain. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2290997/" target="_blank" rel="noopener noreferrer">A 2008 study</a> has shown that even 30 minutes in sunlight (while wearing a bathing suit) can boost vitamin D levels. </p><p><strong>Can sunlight actually prevent cancer? </strong></p><p>Although heavy exposure to sunlight has been proven to contribute to certain skin cancers, a moderate amount of sunlight has actually been shown to have preventative benefits.</p><p><a href="https://cjasn.asnjournals.org/content/3/5/1548.full" target="_blank" rel="noopener noreferrer">According to a 2008 study</a> from the Clinical Journal of the American Society of Nephrology, those who live in areas with fewer daylight hours are more likely to have some specific cancers (including but not limited to colon cancer, ovarian cancer, and prostate cancer) than those who live in areas with increased daylight hours.</p><p><strong>Additionally, sunlight has been shown to help people with skin conditions such as psoriasis. </strong></p><p><a href="http://www.who.int/uv/faq/uvhealtfac/en/index1.html" target="_blank" rel="noopener noreferrer">According to the World Health Organization</a>, sun exposure may also be able to help treat skin conditions such as psoriasis, eczema, jaundice, and acne. <a href="https://www.healthline.com/health/depression/benefits-sunlight#benefits" target="_blank" rel="noopener noreferrer">Some research</a> has also indicated the sun benefits people who struggle with rheumatoid arthritis (RA), systemic lupus erythematosus, and inflammatory bowel disease. </p>
Can you be addicted to the sun?<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNDQyMjI1Ny9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYwMzE5NTMwOX0.pHOWSr3FcIndYkBAVND1UsD8AheTQmxsePKRi3XvYTw/img.jpg?width=1245&coordinates=31%2C0%2C32%2C0&height=700" id="93c87" class="rm-shortcode" data-rm-shortcode-id="384e08fdcd535ed2b792eef419af9e2c" data-rm-shortcode-name="rebelmouse-image" alt="hands holding up the sun" />
The large-scale study examines the link between addiction and sunlight, with some surprising results...
Credit: KieferPix on Shutterstock<p>Addictions are multi-step conditions that, by definition, require exposure to the addictive agent. Due to the increase of serotonin (a chemical in the human body <a href="https://www.healthline.com/health/mental-health/serotonin" target="_blank">that has been proven</a> to help reduce depression, regulate anxiety, and maintain bone health), it's natural that being exposed to prolonged periods of sunlight could become somewhat addictive to the human body and mind. We crave things that make us feel good, and sometimes those cravings become something we depend on. This is the very nature of addiction.</p><p>Countless people are exposed to addictive things (substances, medications, and yes, even the sun), but not all become addicted. This is because of the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3506170/" target="_blank" rel="noopener noreferrer">genetic component of addiction</a>. </p><p>A large-scale study from King's College in London examines more than 260,000 people to better understand how sun-seeking behavior in humans can be linked to genes involving addiction, behavior traits, and brain function. </p><p><strong>The study included two phases:</strong></p><p>Phase one suggested genetics play a role in sun-seeking behaviors and phase 2 helped pinpoint what those genetic markers are.</p><p>Phase 1: The researchers studied the detailed health information of 2,500 twins, including their sun-seeking behavior and their genetics. Identical twins in a pair were more likely to have similar sun-seeking behavior than non-identical twins, indicating that genetics plays a role here. </p><p>Phase 2: The team of researchers then were able to identify five key gene markers involved in this sun-seeking behavior from further analysis of 260,000 participants. Some of the genes indicated have been linked to behaviors traits that are associated with risk-taking and addiction (including smoking and alcohol consumption).</p><p><strong>What does this study really prove? </strong></p><p>Some may think it's natural to become addicted to something that makes you feel good. The physical and mental health benefits of the outdoors have been heavily studied...so what does this study really mean? </p><p>First and foremost, it means more research needs to be done to examine the link between human conditions and exposure to sunlight. Senior author Dr. Mario Falchi explains to the <a href="https://www.kcl.ac.uk/news/addicted-to-the-sun-its-in-your-genes" target="_blank">King's College London News Center</a>: "Our results suggest that tackling excessive sun exposure or use of tanning beds might be more challenging than expected, as it is influenced by genetic factors. It is important for the public to be aware of this predisposition, as it could make people more mindful of their behavior and the potential harms of excessive sun exposure."</p><p>Additionally, it could mean alternative treatments, and further research needs to be conducted in terms of how we treat certain conditions that are caused or heavily influenced by human exposure to sunlight. </p>