{"682797":{"#nid":"682797","#data":{"type":"news","title":"How Was the Wheel Invented?","body":[{"value":"\u003Cdiv\u003E\u003Cp\u003EImagine you\u2019re a copper miner in southeastern Europe in the year 3900 B.C.E. Day after day you haul copper ore through the mine\u2019s sweltering tunnels.\u003C\/p\u003E\u003Cp\u003EYou\u2019ve resigned yourself to the grueling monotony of mining life. Then one afternoon, you witness a fellow worker doing something remarkable.\u003C\/p\u003E\u003Cp\u003EWith an odd-looking contraption, he casually transports the equivalent of three times his body weight on a single trip. As he returns to the mine to fetch another load, it suddenly dawns on you that your chosen profession is about to get far less taxing and much more lucrative.\u003C\/p\u003E\u003Cp\u003EWhat you don\u2019t realize: You\u2019re witnessing something that will change the course of history \u2013 not just for your tiny mining community, but for all of humanity.\u003C\/p\u003E\u003Cp\u003E\u003Ca href=\u0022https:\/\/images.theconversation.com\/files\/669226\/original\/file-20250521-86-2c6okj.png?ixlib=rb-4.1.0\u0026amp;q=45\u0026amp;auto=format\u0026amp;w=1000\u0026amp;fit=clip\u0022\u003E\u003Cimg src=\u0022https:\/\/images.theconversation.com\/files\/669226\/original\/file-20250521-86-2c6okj.png?ixlib=rb-4.1.0\u0026amp;q=45\u0026amp;auto=format\u0026amp;w=754\u0026amp;fit=clip\u0022 alt=\u0022AI-generated image of a wheeled cart inside a mine tunnel.\u0022\u003E\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003EAn illustration of what the original mine carts used in the Carpathian mountains may have looked like in 3900 B.C.E. Kai James via DALL\u00b7E\u003C\/p\u003E\u003Cp\u003EDespite the wheel\u2019s immeasurable impact, no one is certain as to who invented it, or when and where it was first conceived. The hypothetical scenario described above is \u003Ca href=\u0022https:\/\/cup.columbia.edu\/book\/the-wheel\/9780231173384\u0022\u003Ebased on a 2015 theory\u003C\/a\u003E that miners in the Carpathian Mountains \u2013 in present-day Hungary \u2013 first invented the wheel nearly 6,000 years ago as a means to transport copper ore.\u003C\/p\u003E\u003Cp\u003EThe theory is supported by the discovery of \u003Ca href=\u0022https:\/\/ri.abtk.hu\/images\/letoltes_publ\/bondar.maria\/Bondar_Acta_2018_dec_102_tetelhez.pdf\u0022\u003Emore than 150 miniaturized wagons\u003C\/a\u003E by archaeologists working in the region. These pint-sized, four-wheeled models were made from clay, and their outer surfaces were engraved with a wickerwork pattern reminiscent of the basketry used by mining communities at the time. Carbon dating later revealed that these wagons are the earliest known depictions of wheeled transport to date.\u003C\/p\u003E\u003Cp\u003EThis theory also raises a question of particular interest to me, \u003Ca href=\u0022https:\/\/scholar.google.com\/citations?user=CdazOWQAAAAJ\u0026amp;hl=en\u0022\u003Ean aerospace engineer\u003C\/a\u003E who studies the \u003Ca href=\u0022https:\/\/ae.gatech.edu\/directory\/person\/kai-james\u0022\u003Escience of engineering design\u003C\/a\u003E. How did an obscure, scientifically naive mining society discover the wheel, when highly advanced civilizations, \u003Ca href=\u0022https:\/\/www.jstor.org\/stable\/25148110\u0022\u003Esuch as the ancient Egyptians\u003C\/a\u003E, did not?\u003C\/p\u003E\u003Ch2\u003EA controversial idea\u003C\/h2\u003E\u003Cp\u003EIt has long been assumed that \u003Ca href=\u0022https:\/\/doi.org\/10.2307\/2841649\u0022\u003Ewheels evolved from simple wooden rollers\u003C\/a\u003E. But until recently no one could explain how or why this transformation took place. What\u2019s more, beginning in the 1960s, some researchers started to \u003Ca href=\u0022https:\/\/doi.org\/10.1111\/ojoa.12142\u0022\u003Eexpress strong doubts\u003C\/a\u003E about the roller-to-wheel theory.\u003C\/p\u003E\u003Cp\u003EAfter all, for rollers to be useful, they require flat, firm terrain and a path free of inclines and sharp curves. Furthermore, once the cart passes them, used rollers need to be continually brought around to the front of the line to keep the cargo moving. For all these reasons, the ancient world \u003Ca href=\u0022https:\/\/doi.org\/10.1098\/rsos.240373\u0022\u003Eused rollers sparingly\u003C\/a\u003E. According to the skeptics, rollers were too rare and too impractical to have been the starting point for the evolution of the wheel.\u003C\/p\u003E\u003Cp\u003EBut a mine \u2013 with its enclosed, human-made passageways \u2013 would have provided favorable conditions for rollers. This factor, among others, compelled my team to revisit the roller hypothesis.\u003C\/p\u003E\u003Ch2\u003EA turning point\u003C\/h2\u003E\u003Cp\u003EThe transition from rollers to wheels requires two key innovations. The first is a modification of the cart that carries the cargo. The cart\u2019s base must be outfitted with semicircular sockets, which hold the rollers in place. This way, as the operator pulls the cart, the rollers are pulled along with it.\u003C\/p\u003E\u003Cp\u003EThis innovation may have been motivated by the confined nature of the mine environment, where having to periodically carry used rollers back around to the front of the cart would have been especially onerous.\u003C\/p\u003E\u003Cp\u003EThe discovery of socketed rollers represented a turning point in the evolution of the wheel and paved the way for the second and most important innovation. This next step involved a change to the rollers themselves. To understand how and why this change occurred, we turned to physics and computer-aided engineering.\u003C\/p\u003E\u003Ch2\u003ESimulating the wheel\u2019s evolution\u003C\/h2\u003E\u003Cp\u003ETo begin \u003Ca href=\u0022https:\/\/doi.org\/10.1098\/rsos.240373\u0022\u003Eour investigation\u003C\/a\u003E, we created a computer program designed to simulate the evolution from a roller to a wheel. Our hypothesis was that this transformation was driven by a phenomenon called \u201c\u003Ca href=\u0022https:\/\/energyeducation.ca\/encyclopedia\/Mechanical_advantage\u0022\u003Emechanical advantage\u003C\/a\u003E.\u201d This same principle allows pliers to amplify a user\u2019s grip strength by providing added leverage. Similarly, if we could modify the shape of the roller to generate mechanical advantage, this would amplify the user\u2019s pushing force, making it easier to advance the cart.\u003C\/p\u003E\u003Cp\u003EOur algorithm worked by modeling hundreds of potential roller shapes and evaluating how each one performed, both in terms of mechanical advantage and structural strength. The latter was used to determine whether a given roller would break under the weight of the cargo. As predicted, the algorithm ultimately converged upon the familiar wheel-and-axle shape, which it determined to be optimal.\u003C\/p\u003E\u003Cp\u003E\u003Ca href=\u0022https:\/\/images.theconversation.com\/files\/666635\/original\/file-20250508-56-xsvmkr.jpg?ixlib=rb-4.1.0\u0026amp;q=45\u0026amp;auto=format\u0026amp;w=1000\u0026amp;fit=clip\u0022\u003E\u003Cimg src=\u0022https:\/\/images.theconversation.com\/files\/666635\/original\/file-20250508-56-xsvmkr.jpg?ixlib=rb-4.1.0\u0026amp;q=45\u0026amp;auto=format\u0026amp;w=754\u0026amp;fit=clip\u0022 alt=\u0022This diagram shows twelve illustrations, progressing from images of rollers to a wheel-and-axle structure.\u0022\u003E\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003EA computer simulation of the evolution from a roller to a wheel-and-axle structure. Each image represents a design evaluated by the algorithm. The search ultimately converges upon the familiar wheel-and-axle design. Kai James\u003C\/p\u003E\u003Cp\u003EDuring the execution of the algorithm, each new design performed slightly better than its predecessor. We believe a similar evolutionary process played out with the miners 6,000 years ago.\u003C\/p\u003E\u003Cp\u003EIt is unclear what initially prompted the miners to explore alternative roller shapes. One possibility is that friction at the roller-socket interface caused the surrounding wood to wear away, leading to a slight narrowing of the roller at the point of contact. Another theory is that the miners began thinning out the rollers so that their carts could pass over small obstructions on the ground.\u003C\/p\u003E\u003Cp\u003EEither way, thanks to mechanical advantage, this narrowing of the axle region made the carts easier to push. As time passed, better-performing designs were repeatedly favored over the others, and new rollers were crafted to mimic these top performers.\u003C\/p\u003E\u003Cp\u003EConsequently, the rollers became more and more narrow, until all that remained was a slender bar capped on both ends by large discs. This rudimentary structure marks the birth of what we now refer to as \u201cthe wheel.\u201d\u003C\/p\u003E\u003Cp\u003EAccording to our theory, there was no precise moment at which the wheel was invented. Rather, just like the evolution of species, the wheel emerged gradually from an accumulation of small improvements.\u003C\/p\u003E\u003Cp\u003EThis is just one of the many chapters in the wheel\u2019s long and ongoing evolution. More than 5,000 years after the contributions of the Carpathian miners, a Parisian bicycle mechanic \u003Ca href=\u0022https:\/\/transportationhistory.org\/2017\/08\/03\/today-in-transportation-history-1869-a-big-little-invention-for-bicycles\/\u0022\u003Einvented radial ball bearings\u003C\/a\u003E, which once again revolutionized wheeled transportation.\u003C\/p\u003E\u003Cp\u003EIronically, ball bearings are conceptually identical to rollers, the wheel\u2019s evolutionary precursor. Ball bearings \u003Ca href=\u0022https:\/\/www.youtube.com\/watch?v=RihQOUNsN9c\u0022\u003Eform a ring around the axle\u003C\/a\u003E, creating a rolling interface between the axle and the wheel hub, thereby circumventing friction. With this innovation, the evolution of the wheel came full circle.\u003C\/p\u003E\u003Cp\u003EThis example also shows how the wheel\u2019s evolution, much like its iconic shape, traces a circuitous path \u2013 one with no clear beginning, no end, and countless quiet revolutions along the way.\u003C!-- Below is The Conversation\u0027s page counter tag. Please DO NOT REMOVE. --\u003E\u003Cimg src=\u0022https:\/\/counter.theconversation.com\/content\/244038\/count.gif?distributor=republish-lightbox-basic\u0022 alt=\u0022The Conversation\u0022 width=\u00221\u0022 height=\u00221\u0022\u003E\u003C!-- End of code. If you don\u0027t see any code above, please get new code from the Advanced tab after you click the republish button. The page counter does not collect any personal data. More info: https:\/\/theconversation.com\/republishing-guidelines --\u003E\u003C\/p\u003E\u003Cp\u003E\u0026nbsp;\u003C\/p\u003E\u003Cp\u003E\u003Cem\u003EThis article is republished from \u003C\/em\u003E\u003Ca href=\u0022https:\/\/theconversation.com\u0022\u003E\u003Cem\u003EThe Conversation\u003C\/em\u003E\u003C\/a\u003E\u003Cem\u003E under a Creative Commons license. Read the \u003C\/em\u003E\u003Ca href=\u0022https:\/\/theconversation.com\/how-was-the-wheel-invented-computer-simulations-reveal-the-unlikely-birth-of-a-world-changing-technology-nearly-6-000-years-ago-244038\u0022\u003E\u003Cem\u003Eoriginal article\u003C\/em\u003E\u003C\/a\u003E\u003Cem\u003E.\u003C\/em\u003E\u003C\/p\u003E\u003C\/div\u003E","summary":"","format":"full_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EComputer simulations reveal the unlikely birth of a world-changing technology.\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Computer simulations reveal the unlikely birth of a world-changing technology."}],"uid":"27469","created_gmt":"2025-06-16 14:51:53","changed_gmt":"2026-03-19 13:16:54","author":"Kristen Bailey","boilerplate_text":"","field_publication":"","field_article_url":"","location":"Atlanta, GA","dateline":{"date":"2025-06-11T00:00:00-04:00","iso_date":"2025-06-11T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"677232":{"id":"677232","type":"image","title":" The assumption was that the wheel evolved from wooden rollers","body":"\u003Cdiv\u003E\u003Cp\u003EThe assumption was that the wheel evolved from wooden rollers. \u003Ca href=\u0022https:\/\/www.gettyimages.com\/detail\/photo\/new-york-city-ancient-stone-circle-royalty-free-image\/136595864?phrase=ancient%20wheel\u0026amp;searchscope=image%2Cfilm\u0026amp;adppopup=true\u0022\u003ETetra Images via Getty Images\u003C\/a\u003E\u003C\/p\u003E\u003C\/div\u003E","created":"1750085808","gmt_created":"2025-06-16 14:56:48","changed":"1750085808","gmt_changed":"2025-06-16 14:56:48","alt":" The assumption was that the wheel evolved from wooden rollers","file":{"fid":"261114","name":"file-20250505-62-prv9gj.jpg","image_path":"\/sites\/default\/files\/2025\/06\/16\/file-20250505-62-prv9gj.jpg","image_full_path":"http:\/\/hg.gatech.edu\/\/sites\/default\/files\/2025\/06\/16\/file-20250505-62-prv9gj.jpg","mime":"image\/jpeg","size":142258,"path_740":"http:\/\/hg.gatech.edu\/sites\/default\/files\/styles\/740xx_scale\/public\/2025\/06\/16\/file-20250505-62-prv9gj.jpg?itok=AMnnjgfl"}}},"media_ids":["677232"],"related_links":[{"url":"https:\/\/theconversation.com\/how-was-the-wheel-invented-computer-simulations-reveal-the-unlikely-birth-of-a-world-changing-technology-nearly-6-000-years-ago-244038","title":"Read This Article on The Conversation"}],"groups":[{"id":"660364","name":"Aerospace Engineering"},{"id":"1237","name":"College of Engineering"},{"id":"658168","name":"Experts"},{"id":"1214","name":"News Room"},{"id":"1188","name":"Research Horizons"}],"categories":[],"keywords":[{"id":"187915","name":"go-researchnews"}],"core_research_areas":[],"news_room_topics":[{"id":"71881","name":"Science and Technology"}],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Ch5\u003EAuthor:\u003C\/h5\u003E\u003Cp\u003E\u003Ca href=\u0022https:\/\/theconversation.com\/profiles\/kai-james-2263500\u0022\u003EKai James\u003C\/a\u003E, associate professor of Aerospace Engineering, Georgia Institute of Technology\u003C\/p\u003E\u003Ch5\u003EMedia Contact:\u003C\/h5\u003E\u003Cp\u003EShelley Wunder-Smith\u003Cbr\u003E\u003Ca href=\u0022mailto:shelley.wunder-smith@research.gatech.edu\u0022\u003Eshelley.wunder-smith@research.gatech.edu\u003C\/a\u003E\u003C\/p\u003E","format":"limited_html"}],"email":[],"slides":[],"orientation":[],"userdata":""}}}