Posts Tagged ‘birds’
“It is entirely possible that you get unpredictable behavior out of predictable rules”*…
For centuries, the hypnotic winter flights of starlings were thought to be telepathy. Today, science reveals a much darker reality. Behind one of nature’s most breathtaking visual displays lies a mathematical masterpiece built entirely on fear. From The Great Planet…
During the autumn and winter months, if you look to the skies over Europe and North America about an hour before sunset, you might witness one of nature’s most breathtaking visual spectacles. These massive black clouds of tens of thousands of European starlings (Sturnus vulgaris)—constantly shifting into spheres, planes, and waves—are known in the scientific community as a “murmuration.” Named after the deep, resonant sound produced by thousands of wings beating in unison, the phenomenon looks from afar like a colossal calligraphy brushstroke across the sky or a ball of fire flickering in the wind. Yet, beyond this aesthetic illusion lies a ruthless and flawless algorithm for survival.
For centuries, researchers were baffled by how tens of thousands of birds could fly at speeds of around 45 kilometers per hour without a single collision. This coordination was so inconceivable that in 1931, prominent ornithologist Edmund Selous described it as “a madness in the sky.” To Selous, there was only one logical explanation for this complex behavior: telepathy. “They must think collectively, all at the same time,” he wrote.
Like many others, Selous assumed that complex behavior must stem from equally complex origins. However, groundbreaking observations made in 2005 by the married physicists Andrea Cavagna and Irene Giardina from the rooftop of the Palazzo Massimo in Rome revealed a truth far more striking than telepathy. Over three years of chilly evenings, the team used pairs of cameras to reconstruct the 3D positions of more than 4,000 birds in a single flock, proving that there is no overarching plan and no leader. Each starling in the flock interacts exclusively with its seven closest neighbors—a number researchers suggest might be the maximum capacity their brains can handle. The starlings do not keep track of these constantly changing alliances; they simply align their flight path with whichever seven birds are nearest, remaining close, but never too close.
The birds do not need to engage in complex communication to navigate their massive trajectories. When Charlotte Hemelrijk of the University of Groningen in the Netherlands plugged just three simple rules—avoidance, alignment, and attraction—along with basic aerodynamics into a computer model, the resulting virtual murmuration perfectly matched the real-world data gathered in Rome.
Physicists explain this vast web of interaction through the concept of “scale-free correlation.” When a starling turns, this new alignment influences its neighbors, who in turn influence theirs. Yet, unlike a children’s game of telephone, this transfer of information does not degrade with errors; instead, the errors are entirely washed away in the movement. No matter how large the flock becomes, the information arrives at the furthest edge completely uncorrupted. Even though each bird only pays attention to seven neighbors, its senses effectively extend across the entire murmuration, allowing it to instantly react to a movement hundreds of birds away. The reason the flock looks like a single entity from the outside is that, physically, it truly behaves like one.
Why do starlings expend such an immense amount of energy to constantly shift shape in the sky? For a long time, the scientific consensus leaned toward the “warmer together” hypothesis, assuming the displays served to advertise a roosting site and gather more birds for thermal benefits on cold nights. However, an analysis of over 3,000 murmurations across 23 countries, gathered through citizen science, revealed only a weak negative correlation between temperature and flock duration. The true determining factor was the “safer together” principle: defense against predators.
In approximately 30% of the recorded murmurations, birds of prey such as hawks, falcons, or harriers were present. As predators approached or actively engaged the flock, both the duration and the size of the murmuration increased…
… Millions of years of evolution have granted starlings this colossal collective intelligence, allowing them to outmaneuver even nature’s most apex aerial predators. Yet, the primary threat they face today comes not from the sky, but from human activity on the ground. While European starlings are omnivorous, they rely heavily on insect larvae, such as leatherjackets, that live in the soil beneath grasslands; as these grassy areas vanish, so does their food supply. Their habitats are rapidly shrinking due to urbanization and changing farming practices, such as moving livestock feed indoors…
… For a species to merely exist within an ecosystem, narrowly avoiding physical extinction, does not mean it has truly been saved. Earth’s most beautiful phenomena only emerge when living things can act together in great, thriving numbers. You can evolve a flawless biological algorithm based on scale-free correlation to outwit nature’s most ruthless predators, but when your habitat is suddenly paved over with concrete, evolution affords you no time to design a new defense mechanism. The fact that we have finally decoded the mathematical secret of the starling murmuration just as we are on the verge of losing it forever remains one of the most haunting questions suspended in our skies—a stark reflection of modern human hubris and our destructive relationship with the planet…
A flawless algorithm is fading from our skies: “The Mathematics of Fear: Why Starlings Murmurate.”
See also: “The brain has corridors surpassing / Material place.”
* Frank Heppner (an ornihologist who helped create the first computer simulations of bird flocks in flight)
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As we fly, we might send beautifully-plumed birthday greetings to Elliott Coues; he was born on this date in 1842. An army surgeon, historian, writer, and geographer, he led surveys of the Arizona Territory, first in his army posting there and later as secretary of the United States Geological and Geographical Survey of the Territories.
But we remember him here for his lifelong pursuit of his boyhood passion for birds. As a teen, he met many naturalists at the Smithsonian Institution and published his first ornithological paper in 1859, at age 19. As his army assignments took him to various locations throughout the West, he continued studying the bird life in each new area, and found new species. His Key to North American Birds (1872) was the first work of its kind to present a taxonomic classification of birds according to an artificial key and promoted the systematic study of wild fowl in North America. He founded the American Ornithological Union in 1883, and was editor of its publication, The Auk.
“The one who plants trees knowing that he or she will never sit in their shade, has at least started to understand the meaning of life”*…
… Yes, and, as John Parker and Justin Nowakowski explain, it turns out that what and how we plant matters enormously…
Around the world, people plan to plant more than 1 trillion trees this decade in an ambitious effort to slow climate change and reduce biodiversity loss. But if the past is prologue, many of those planted trees won’t survive. And if they do, they could end up as biological deserts that lack the richness and resilience of healthy forests.
It doesn’t have to be this way.
The United Nations declared 2021-2030 the Decade on Ecosystem Restoration to encourage efforts to repair degraded ecosystems. Tree planting has become a centerpiece of that effort, championed by initiatives such as the Bonn Challenge and the Trillion Trees Campaign.
However, many tree-planting commitments have a critical flaw: They rely too heavily on monoculture plantations – vast areas planted with just a single tree species.
Monoculture plantations are generally one-way tickets to producing wood. But these high-yield plantations are high risk and can be surprisingly fragile. When drought, pests, or forest fires strike, entire monoculture plantations can fail at once. In one example, nearly 90% of 11 million saplings planted in Turkey died within three months due to drought and lack of maintenance.
Forests are more than just timber factories. They regulate water, store carbon, provide habitat for wildlife, cool the landscapes around them and even provide human health benefits.
Rather than gambling on a single species and hoping for the best, science now points to a smarter path that captures both ecological and economic benefits while minimizing risk: mixed-species plantings that mirror the biodiversity of a natural forest, ultimately creating forests that grow faster and are more resilient in the face of constant threats.
We are community and landscape ecologists at the Smithsonian Environmental Research Center. Since 2013, we and our colleagues have been rigorously testing this idea in a large, ecosystem-scale experiment called BiodiversiTREE. The verdict is striking: Trees in mixed forests don’t just survive – they outgrow their monoculture counterparts and support dramatically more biodiversity…
[Parker and Nowakowski outline their project, unpack it’s (impressive) results, and explore the challenges to sclaing their example. They conclude..]
… The stakes are high. Restoration has become a major global investment, with hundreds of billions of dollars already being spent annually. Getting it wrong means wasted resources and missed opportunities to address some of the most pressing environmental challenges of our time.
If the world is going to plant a trillion trees, we believe it needs to do more than just put seedlings in the ground. It needs to rethink what a forest should be.
The goal isn’t just to grow trees. It’s to grow forests that last.
Eminently worth reading in full: “Don’t just plant trees, plant forests to restore biodiversity for the future,” from @johndparker.bsky.social and Justin Nowakowski in @us.theconversation.com.
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As we see the forest, we might send observant birthday greetings to a man who spent a good bit of time in and around forests, John James Audubon; he was born on this date in 1785. An ornithologist, naturalist, and artist, Audubon documented all types of American birds with detailed illustrations depicting the birds in their natural habitats. His The Birds of America (1827–1839), in which he identified 25 new species, is considered one of the most important– and finest– ornithological works ever completed.
“When words become unclear, I shall focus with photographs. When images become inadequate, I shall be content with silence.”*…
As Josh Begley elegantly demonstrates, silence may be nigh…
The New York Times published its first issue on September 18, 1851, but the first photos wouldn’t appear on the cover until the early 1900s over 60 years later. This visual timeline by self-described data artist Josh Begley captures the storied newspaper’s approach to layout and photography by incorporating every NY Times front page ever published into a single one-minute video. The timelapse captures decades text-only front pages before the newspaper began to incorporate illustrated maps and wood engravings. The liberal usage of black and white photography begins a century later and finally the first color photo appears in 1997. What a fascinating way to view history through image, over 60,000 front pages in all…
Showing instead of (simply) telling: “The Rise of the Image: Every NY Times Front Page Since 1852 in Under a Minute,” from @thisiscolossal.com (who found it via @kottke.org).
See the animated visualization here or here.
(TotH to EWW)
* Ansel Adams
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As we ponder the prevalence of pictures, we might spare a thought for a man who made powerful– and beautiful– use of images, John James Audubon; he died on this date in 1851. An ornithologist, naturalist, and artist, Audubon documented all types of American birds with detailed illustrations depicting the birds in their natural habitats. His The Birds of America (1827–1839), in which he identified 25 new species, is considered one of the most important– and finest– ornithological works ever completed.
Happy Mozart’s Birthday!
“Nature does not hurry, yet everything is accomplished”*…
Paul Constance on a chain of dedicated scientists who are building data sets on the natural world around us, and how– coupled with emerging new nature apps that enable citizen scientists– they are expanding our ecological attention span into the long now…
Every two weeks from March to November, Chris Halsch walks a ten-mile loop near the Donner Pass, high up in California’s Sierra Nevada, for the sole purpose of counting butterflies.
It is one of five sites at various altitudes that Halsch, a PhD candidate at the University of Nevada, Reno, has been visiting with metronomic regularity for the past five years. At each one he retraces his steps, pausing every so often to jot down species and numbers in a notebook.
Along the way, he sometimes meets recreational birders or hikers who take photographs and use nature apps to identify species for fun. But unlike those random snapshots, Halsch’s notes are a coveted resource for scientists. Once he types them into a spreadsheet, each of his data points adds a new segment to a chain of observations that has been growing without interruption for half a century, in one the world’s longest-lived efforts to monitor butterfly populations. Like a relay runner, Halsch is extending a marathon of sustained attention that began 20 years before he was born.
Multi-decadal time-series of field observations are among the rarest and most valuable artifacts in ecosystem science because they help to overcome a peculiar weakness in our ability to perceive and interpret the natural world. Humans have developed powerful methods for reconstructing events in the distant past, from the birth of a galaxy to mass extinctions in the Devonian. We have built instruments that can parse the present down to the zeptosecond. But when it comes to the modest timescale of our own lifespans, we are like near-sighted moles.
Weren’t there more birds in this meadow when we were kids?
Doesn’t it seem like spring is a lot rainier than it used to be?
Are you sure it’s safe to eat fish from this river?
Our answers to these types of questions are notoriously unreliable. Think of the tendency to describe a single weather event as evidence for (or against) climate change, or the panic caused by invasive zebra mussels that, 20 years later, turns out to have been misplaced. Perceptions are distorted by selective memories, cognitive biases, political agendas and shifting baseline syndrome—the propensity of each generation to gradually forget past environmental conditions and accept present ones as normal. In an essay published in 01990, the zoologist John J. Magnuson wrote that this temporal myopia can trap us in the “invisible present,” a space where we fail to see slow changes and are unable to interpret effects that lag years behind their causes. “In the absence of the temporal context provided by long-term research, serious misjudgments can occur not only in our attempts to understand and predict change in the world around us, but also in our attempts to manage our environment,” he warned.
Magnuson was echoing a group of mid-century scientists who believed that some of the biggest questions in ecology could only be answered with field observations that were carefully structured and repeated at the same sites for at least two decades. The longer the time-series, the greater likelihood that the invisible present will “melt away,” exposing the complex and often unexpected dynamics of ecosystem change….
[Constance describes a variety of efforts underway…]
… Collectively, these efforts are widening the aperture of our ecological attention, enabling scientists to find and stitch together scattered fragments of temporal data into panoramas that tell a more illuminating story about the interactions that drive change. Unfortunately, the emerging picture is still largely focused on wealthy countries—particularly ones with long histories of field-based science. A map of the International LTER network, an association of 750 field stations that, like their U.S. counterparts, are making long-term observations, shows that more than two thirds are concentrated in Western Europe. Numerous countries in Asia, Africa and Latin America have no stations at all. Moreover, even as scientists like Moran and Grames are exploiting the new wealth of temporal evidence, it is not clear how this research will influence the wider culture, where the blinkered perceptions of the “invisible present” are still pervasive.
The trend that may ultimately overcome both of these limitations is driven, paradoxically, by smartphones. Non-scientists have long been a critical source of field labor for long time-series, most famously for the Audubon Society’s 122-year-old Christmas Bird Count, but also in hundreds of smaller projects that monitor other kinds of flora and fauna. Now, smartphones with powerful cameras and apps such as eBird, iNaturalist, Seek and Picture Insect have enabled millions of casual observers to supplement this pool of dedicated volunteers. Despite the lively debate on whether smartphone usage in the outdoors enhances or interferes with people’s appreciation of nature, one fact is clear: because nature apps automatically time-stamp, geo-reference and store each observation in a robust database, they are generating potential time-series at an unprecedented scale.
In the 20 years since the Cornell Lab of Ornithology launched eBird, the app has amassed more than one billion observations by 700,000 birders from every country in the world. Carrie Seltzer, who heads stakeholder engagement at iNaturalist, says that more than 2.4 million people have made observations on the app, at a rate that has grown between 50 percent and 100 percent per year since 02012… This torrent of raw field data vastly exceeds what even well-funded researchers could ever dream of gathering with traditional methods…
Understanding the world around us: “Peering into The Invisible Present,” from @presentbias and @longnow. Eminently worth reading in full– then browsing the other remarkable pieces available on the Long Now website.
* Lao Tzu
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As we take the long view, we might send insightful birthday greetings to a man who encourages us to see in different ways, M. C. Escher; he was born on this date in 1898. A graphic artist inspired by mathematics, he created woodcuts, lithographs, and mezzotints, that— while largely ignored by the art world in his lifetime, have become widely celebrated. He’s been recognized as an heir to Parmigianino, Hogarth, and Piranesi.
His work features mathematical objects and operations including impossible objects, explorations of infinity, reflection, symmetry, perspective, truncated and stellated polyhedra, hyperbolic geometry, and tessellations. And though Escher believed he had no mathematical ability, he interacted with the mathematicians George Pólya, Roger Penrose, and Donald Coxeter, and the crystallographer Friedrich Haag, and conducted his own research into tessellation.
For more on (and more examples of) Escher’s work, see here.
“The daily hummingbird assaults existence with improbability”*…
Zito Madu‘s lovely meditation on– and appreciation of– the hummingbird…
… Hummingbirds are wondrous creatures. As Katherine Rundell wrote in her 2022 essay “Consider the Hummingbird”:
There is nothing I admire more than evolution. But it’s difficult, more than with any other living thing, to imagine hummingbirds beginning as archaebacteria among primordial murk, painstakingly working over millions of years to grow bright wings. They seem as if they were made in an instant, a spark of genius from an extravagant god.
They are the smallest living birds in the world. There are 366 known species of hummingbirds, with the smallest being the bee hummingbird that measures at two inches, and the largest being the giant hummingbird, which is 9.1 inches long. Most live in the tropics, largely in Central and South America, but there are around seventeen species in the United States. They have long needle-like beaks, can fly forward, backward, up, down, and in zigzags. They flap their wings faster than any other bird, up to fifty times per second, they have the largest heart-to-body-size rate in an animal, and that heart has typically 500 to 1200 beats per minute, according to The Hummingbird Handbook (2021) by John Shewey. When in a state of deep rest, and to conserve energy, the hummingbird can slow down its heart rate to only fifty beats per minute, and drop its metabolism by 95 percent.
In 2022, a study was published by Yale scientists on the range of colors in the plumage of hummingbirds, which “exceeds the known diversity of colors found in the plumages of all other bird species combined, increasing the total of known bird-visible plumage colors by 56 percent.”…
“Hummingbirds are Wondrous,” from @_Zeets in @Plough.
* Ursula K. Le Guin, No Time to Spare: Thinking About What Matters
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As we appreciate abundance, we might send bucolic birthday greetings to Ralph Waldo Emerson; he was born on this date in 1803. An essayist, lecturer, philosopher, abolitionist, and poet, he articulated the philosophy of Transcendentalism in his 1836 essay “Nature.”
A mentor and friend of Henry David Thoreau, a fellow Transcendentalist, and remains among the linchpins of the American romantic movement.
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