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In the village of Bellewstown, about 15 miles north of Dublin, Ireland, they still talk about what Barney Curley did back in 1975. It all happened during a horse race on the Hill of Crockafotha. It was just an amateur jockey race on a lazy summer day in a sleepy, remote town; it wasn’t meant to be anything special. The last thing anyone expected was to witness the making of history. The race in question occurred on 26 June 1975. Barney Curley–our protagonist, if you could call him that–owned one of the horses running later that day. But at the racecourse, as preparations were being made, Curley was nowhere to be seen. And not because he wasn’t in attendance–it was because he was taking great pains to stay out of sight. If the trackside bookmakers caught wind that he was at Bellewstown that day, or if they discovered that he was the owner of one of the horses, they would be on full alert, and take precautions with the wagers and odds. Curley had earned a reputation in horse racing circles–he was known to engage in some gambling shenanigans from time to time. But the shenanigan he was planning that day was his most ambitious to date, hands-down. As the spectators placed their wagers and settled in around the edge of the track for a pleasant afternoon of laid back horse racing, Curley was concealed in the thicket of gorse shrubs in the center section of the oval-shaped track. This particular infield wasn’t ideal for human occupation, it was all dust and thorns. Nevertheless he stood in his trademark felt fedora, shrouded by tall shrubbery, far from the other spectators, a pair of binoculars pressed to his eyes. In the distance the loudspeaker announced, “They’re off!” Curley tugged his hat down tight over his bald head as if he could hide inside of it, and peered through his field glasses toward the rumble of horse hooves. In the next five minutes, if everything went according to plan, all of Barney Curley’s considerable money troubles would be over. If the plan went sideways–if his animal was not up to the task, or there was one inopportune stumble–he would be utterly ruined. Continue reading ▶
In certain dialects of Chinese, Japanese, Korean, and Vietnamese, the word for ‘four’ sounds very similar to the word for ‘death’1. Consequently, the number 4 is considered by many people in East Asian nations to be unlucky. It is not unusual for buildings in that region to skip the number 4 when labeling floors, much in the same way 13th floors are omitted in some parts of the world2. In Hong Kong, at least one skyscraper avoids the proper numbering for floors 40-49. Four is the smallest positive non-prime number3. It is the only natural number where one can get the same result by multiplying its square roots (2×2), or adding them (2+2). Four happens to be the only number that has the same number of letters as its actual value4. The four color theorem tells us that four is an adequate number of colors for any two dimensional map–no two bordering regions would need to share a color. Four is the number of bonds that a carbon atom can make, which is why life can exist, a quality known as tetravalency. Fear of the number four is known as tetraphobia, and anyone suffering from it has almost certainly stopped reading by now, or at least uttered some four-letter words. It’s no secret that direct donations to Damn Interesting have been on a downward trend in recent years, so we are aiming to diversify. To that end, we’ve made something new, and it’s called Omiword. Continue reading ▶
Edmund Lawall must have felt cursed. He’d brought his family to New York in the late 1800s to carry on his father’s business as a pharmacist, but fate—or perhaps the city itself—seemed determined to drive him back out again. Lawall’s health had been in decline since their arrival, and his wife’s kidney disease had worsened, despite all of the tinctures and patent medicines available to his turn-of-the-century expertise. Not long after that, his business partner had been revealed as a crook, sending Lawall scrambling into bankruptcy court to convince the judge that his pharmacy had nothing to do with shady real estate dealings. Then, in the midst of the bankruptcy proceedings, an anonymous woman had staggered into Lawall’s drug store, collapsed on the floor, and died of unknown causes. Likely no one could have saved her, but it wasn’t exactly a ringing endorsement of the pharmaceutical services available at the corner of Eighth Street and Avenue C. None of that compared, however, to the morning of 27 June 1906, when a disheveled man in a medical coat burst through the narrow glass doors of the pharmacy, begging for protection. He was immediately followed by a young man with a revolver, and an angry crowd screaming in Yiddish. Lawall didn’t speak the language, but there was no mistaking the young man’s intent as he strode purposely forward and raised his gun to the doctor’s head. It was a grim, but recognizable tableau: the young man’s stance and grip were confident, clearly marking him as a budding gangster. The behavior of the crowd, on the other hand, made no sense at all. Innocent bystanders tended to run away from gang violence, yet the pushcart vendors and housewives surrounding the apparent holdup were not frightened, or even appealing for mercy. They were shouting, quite insistently, for the doctor’s execution. And everything seemed to indicate they were going to get what they wanted. In the weeks that followed, blame would be pointed in nearly every direction—because at that moment, unbeknownst to Lawall, similar scenes were playing out all over the neighborhood, with other doctors, teachers, reporters, and even utility workers being assaulted by hordes of people howling at them in Yiddish. By the time it was over, the incident would be measured as one of the largest riots ever in New York City, and the confrontation at Lawall’s Pharmacy would be mentioned only in passing, if at all. Another name, however, would be repeated over and over again: Adeline E. Simpson, the principal of Public School No. 110. Continue reading ▶
Iceland is known to the rest of the world as the land of Vikings and volcanos, an island caught between continents at the extremities of the map. Remote and comparatively inhospitable, it was settled only as long ago as the 9th century, and has seen little additional in-migration since. Even today, more than 90 percent of Iceland’s 390,000 residents can trace their ancestry back to the earliest permanent inhabitants, a Nordic-Celtic mix. The tradition of the Norse sagas lives on in the form of careful record-keeping about ancestry—and a national passion for genealogy. In other words, it is not the place to stumble upon old family mysteries. But growing up in the capital city of Reykjavík in the 1950s, neurologist Dr. Kári Stefánsson heard stories that left him curious. Stefánsson’s father had come from Djúpivogur, an eastern coastal town where everyone still spoke of a Black man who had moved there early in the 19th century. “Hans Jónatan”, they called him—a well-liked shopkeeper who had arrived on a ship, married a spirited woman from a local farm, and became a revered member of the community. The local census did record a man by the name of Hans Jónatan, born in the Caribbean, who was working at the general store in Djúpivogur in the 19th century—but that was all. No images of the man had survived, and his time in Iceland was well before any other humans with African ancestry are known to have visited the island. If tiny, remote Djúpivogur did have a Black man arrive in the 19th century, the circumstances must have been unusual indeed. It was an intriguing puzzle—and solid grounds for a scientific investigation. Given the amount of homogeneity in the baseline Icelandic population, the genetic signature of one relative newcomer with distinct ancestry might still stand out across a large sample of his descendants. Geneticists thus joined locals and history scholars, and they pieced together a story that bridged three continents. Continue reading ▶
It’s been a busy summer, and the large shortfall in donations last month has been demoralizing, so we’re taking a week off to rest and recuperate. The curated links section will be (mostly) silent, and behind the scenes we’ll be taking a brief break from our usual researching, writing, editing, illustrating, narrating, sound designing, coding, et cetera. We plan to return to normalcy on the 11th of September. (The word “normalcy” was not considered an acceptable alternative to “normality” until 14 May 1920, when then-presidential-candidate Warren G. Harding misused the mathematical term in a campaign speech, stating that America needed, “not nostrums, but normalcy.” He then integrated this error into his campaign slogan, “Return to Normalcy.” Also, the G in Warren G. Harding stood for “Gamaliel.”) While we are away, on 06 September 2023, Damn Interesting will be turning 18 years old. To celebrate, here are the first emojis to ever appear in the body of a Damn Interesting post: 🎂🎉🎁 If you become bored while we are away, you might try a little mobile game we’ve been working on called Wordwhile. It can be played alone, or with a friend. If you enjoy games like Scrabble and Wordle, you may find this one ENJOYABLE (75 points). Launch Wordwhile → And, as always, there are lots of ways to explore our back-catalog. View this post ▶
More in science
One reason it's been so hard to directly detect the dark matter is that we're not sure what it is. […]
Back in the ancient mists of time, scientists and mathematicians would circulate preprints of their articles among friends and colleagues via the postal service, as a courtesy, to get feedback and to try to make sure people in the community were aware of their forthcoming work. As the wikipedia entry says, with the advent of widespread LaTeX and the development of the web, Paul Ginsparg (then at LANL) put together an html-based site for electronic sharing of preprints, initially at xxx.lanl.gov (back before "xxx" in URLs was the kind of thing filtered and blocked by employers). In 2001 he moved to Cornell, and by then the lab was perhaps relieved to see the site, rebranded as the arXiv, shift to Cornell's library/repository infrastructure. PIs my age remember (fondly? maybe?) the old days of the arXiv, when Prof. Ginsparg's rather dry sense of humor pervaded the site. The skull-and-crossbones logo. The "help"/FAQ pages that basically said, "if you can't figure out how to .tar.gz all of your necessary LaTeX files, and you can't figure out how to make your .eps figures small, maybe you should reconsider whether you're smart enough to be sharing your ideas here". The arXiv was for preprints, without peer review (though interesting follow-on sites like Scirate now exist for organized commenting on the articles). From these modest beginnings, the arXiv has grown enormously, including imitators/spin-offs such as chemrxiv and biorXiv and socarXiv. The arXiv has recently become an independent nonprofit, hired a CEO, secured multiyear philanthropic support, and hosts over 3 million articles. It's been interesting seeing some level of complaints online about some of these steps, but when the audience is so large, not everyone is going to be happy. Rapid growth has been a major issue - see here for a graph of monthly submissions: The exponential rise (except for a slight pandemic-correlated shoulder) has been problematic, especially recently. One hallmark of the arXiv over the years has been its ability to function with comparatively minimal need for "moderation". Early on, one consequence of the minimalistic help and moderate technical entry barrier was that it was unusual for fringe/pseudoscience to make its way onto the server. (Hence the establishment of viXra.) With the ease of cranking out properly formatted readable manuscripts using AI, clearly the arXiv has been struggling. If 10-15% of submissions need some kind of human intervention or review, the support needs are rapidly outpacing the limited count of support staff. There can be substantial backlogs. To help deal with this, the arXiv recently updated its policies regarding AI-generated content (and AI cannot be a co-author, because the AI tools cannot take responsibility for content), and most recently has had to limit submission rates to two papers per month per submitting author. These moves, too, have drawn some criticism (e.g. here). Personally, I think the operators of the arXiv face an incredibly challenging environment and are doing the best they can - the idea that they are making moves because they are establishment sticks in the mud who don't understand the New Way of Doing Science is just wrong-headed. It's completely unclear where all this is heading. Exponential growth in nature signals instability and does not continue forever. If proponents of very heavily AI-driven research want to establish a repository specifically for that work, that's up to them. [It is very on brand for the hard core AI advocates to argue that the arXiv is somehow morally obligated to host everything (regardless of hardware or personnel costs) so that future AI tools can read everything (a repository growing too quickly for human researchers to keep up) and summarize it.] One overarching point that should come up in any arXiv discussion: The arXiv has become a global repository for an enormous amount of human knowledge, without charging anyone publication fees. This should make interested parties think reallllllly hard about economic models of for-profit publishers.
Is philosophy real? We sent our correspondent to find out.
Stephen J Gould (still my favorite science essayist) wrote an excellent article in 1985 (Red Wings in the Sunset, later published in his book, Bully for Brontosaurus) about artist and naturalist Abbott Handerson Thayer. Thayer wrote about how animals use coloration as camouflage – what he called “cryptic coloration”. His ideas were solid, but he made a classic mistake that scientists sometimes make, overapplying their key discovery. Thayer argued that all animal coloration is cryptic. For example, he argued that flamingos are pink because it hides them in the setting sun (hence the title of the essay). This is a transparently absurd argument, and it shows how Thayer tried to shoehorn all evidence into his preferred and absolute narrative. It is better to assume that nature is complex, and all explanations are at best partial (unless proven otherwise). Animal coloration, in fact, can serve many different purposes, only one of which is camouflage. Thayer also struggled with the male peacock, for example. Butterflies appear to be another example. Actually, many butterflies are camouflaged on the underside of their wings, so that when they are at rest with their wings up they tend to blend into their surroundings. But the top side of their wings are often very colorful and not camouflaged at all. One assumption is that the brightly colored part of their wings is to attract mates. This may be true, but that does not mean the coloration does not serve another function. Often animals use visual cues when choosing their mates that are markers for health and success. As evidence that butterfly wing color may be serving a survival benefit, if you look at birds that feed on insects during flight, they target dully-colored moths much more than brightly colored butterflies, even though the butterflies should be easier to see. A recent study tests the hypothesis that the brightly colored and patterned top side of butterfly wings may have evolved to produce an optical illusion to confuse predators. The idea of using optical illusions as visual protection in animals is not new. For example, zebra stripes allow zebras to hide in the herd, confusing predators as to where one zebra ends and another begins. Stripes on zebras and snakes may also serve to confuses predators about their direction of motion, but this hypothesis has not been tested previously. The researchers started by filming butterflies taking off using high speed cameras. They found that the wing patterns created a powerful “barber pole” illusion. The stripes on a barber pole look like they are moving up or town even when the pole is just spinning. Similarly, the wing patterns combined with the way butterflies move their wings and their flight dynamics combine to create a similar barber pole illusion, making the butterfly look like it is moving down when it is in fact moving up. They also showed that this strategy is phylogenetically widespread. They then did modeling in silico and showed digital creatures converge on butterfly-like patterns. To understand how effective this strategy can be it’s important to understand how catching a butterfly in midflight works. Butterflies have a very jumpy pattern of flight. In order to grab them in flight, a bird will have to zero in on their exact location with a few hundred millisecond and millimeter precision. If the butterfly suddenly zigs while the bird perceives that they zagged, the birdy will miss. Alternatively they may make only a glancing blow or grab an edge of a wing rather than their body. Either way, the butterfly lives another day and the bird goes hungry. In zebras this effect has been referred to as the “visual dazzle” strategy. Now there is some empiric evidence that this works not just by confusing predators, but by creating a specific optical illusion. Zebras will also zig-zag to evade predators, and misjudging that last second movement can cause a pouncing lioness to miss. There are two specific illusion effects at work – the aperture effect and spatiotemporal aliasing. The aperture effect refers to the brain’s processing of visual information through a limited field of view. The visual system has a hard time processing many moving stripes, and specifically will confuse the direction of movement (this is the barber pole effect). So a predator may miss a zebra’s vertical movement, for example, and perceive all movement as perpendicular to the stripes. They may also misinterpret the angle of movement and only perceive the perpendicular motion. Spatiotemporal aliasing has to do with ratio of the movement with the “refresh” speed of the brain’s visual processing. You have likely seen this with spinning wheels that have spoke-like features. As the wheel slows down, at one point the spinning will appear to stop completely, and then will appear to spin backwards. This is simply an artifact of your brain’s visual processing speed. Now imagine being surrounded by a field of rapidly moving and zig-zagging stripes, and your brain trying to make sense of all this information, while trying to compensate for these powerful optical illusions. Butterflies don’t have a herd to hide in, but they do have the added element of their flapping wings. Not only are they moving in a way to maximize these optical illusions, their wings are also doing this, while alternating top-side and bottom-side. Some butterflies have bright spots on their colorful upper wings, that will flash as they flap their wings, causing another type of dazzling disorientation. I will end by returning to my original point – do not be limited in the types of explanations that you reach for when trying to understand nature. Nature is not so limited. Animals do not just use coloration for camouflage and attracting mates. They can also use their coloring for thermoregulation, for mimicking other animals, for producing a danger-signal to would-be predators, and to communicate with other members of their species. It can communicate mood, danger, or social status. Now we have to add optical illusions to the list. There may be other strategies yet to be discovered or imagined. The post Butterflies Are Masters of Illusion first appeared on NeuroLogica Blog.
