Showing posts with label science. Show all posts
Showing posts with label science. Show all posts

Tuesday, August 04, 2026

Can science be rescued?

 kw: book reviews, nonfiction, science, history of science, scientists, biographies, inquisition, polemics

At the defense of my PdD dissertation, one prominent professor growled, "This isn't geology, it is computer science." To a certain extent, he was right. I was surprised that he was the one to say it, though, for among the faculty he was the most computer-literate. I had used a great deal of computer modeling and simulation in conjunction with my research. This was 1983, and the geology faculty in general were much more comfortable out in the field with a rock hammer than they were poking at a computer terminal connected to a mainframe computer hidden away in the basement of the Electrical Engineering building. Desktop personal computers were rare. On the other hand, I was quite computer literate, and I was at that time an adjunct professor of computer science.

That wasn't the only objection to my work. I'll discuss that in a moment. The turning point from interview to inquisition began when someone asked, "Do you really believe this stuff?" I answered, "Believe? That's the wrong word. 'This stuff' cannot save my soul. I believe in Jesus. But 'this stuff' is the best scientific explanation for the phenomena we observe." Hostility ensued. I felt like St. Sebastian, who was tied to a tree where archers used him for target practice.

I had spent a few years of research to determine what effect directional heat flow in Earth's crust might have on the emplacement of "gneiss domes" such as the Black Hills of South Dakota. My supervising professor and I went all over the Black Hills to gather specimens of rocks that had originally underlain the domed structure and rocks in the lowest layers above the granitic/gneiss core of the Hills.

I needed to determine the thermal conductivity of these rocks in three directions. I used a large core drill to cut out cylinders, which I sliced into sections a centimeter or so in thickness, and then I polished the flat surfaces for use in a special press with heaters and thermocouples. I still have some of these. I call them my "hard disks".

The ratio of heat flow across the grain, versus along the grain, is the thermal anisotropy. For a pure, platy mineral such as mica, I found that this ratio could be as high as 6:1. For the shales and schists in the lower sections of the Black Hills, I measured thermal anisotropy between 1.2:1 and 1.6:1. The initial discussions of the early results with my committee were not encouraging. I did a series of computer simulations which showed that the excess heating caused just by thermal anisotropy was no more than a few degrees.

As it happened, I spent time that summer on a project about fluid flow. Another graduate student and I found that the anisotropy of fluid flow in layered rocks could be quite high, 10:1 to 100:1 and even greater. Any fluid flowing through these rocks would be very strongly affected by this directional fabric, and the solid-rock thermal anisotropy wouldn't matter at all. As a side project, the student and I dug into literature and studies about fluid flow in the crust. We determined that even in "dry rock" there is water, and it is in motion, and if there is any heat flow it is directed almost entirely by fluid flow. This was new; there was no literature on this particular point.

Therefore, I wrote a dissertation in which I stated that my initial theory was not tenable, and that further study would be needed to quantify the results of anisotropy in fluid flow. This was quite unpopular and it apparently stepped on a few toes. It was "this stuff" that caused my committee along with the other gathered faculty to reject my dissertation. I became, not a PhD, but AbD, "all but dissertation". Coda: I had an established relationship with scientists at a national laboratory in California. I passed my materials on to them, and they were glad to have them.

With such a background, I was well primed to receive Matt Kaplan's historical survey of scientific mavericks in I Told you So! Scientists Who Were Ridiculed and Imprisoned for Being Right

The book is in part a biography of Ignaz Semmelweis, the best-known of those who learned how necessary it is to clean a doctor's hands and equipment before treating a patient. Semmelweis was also the one who seems to have suffered the most for it. The various parts of his life story are woven with others. The book opens with a scene in which a graduate student named Alison, at a poster session, is being shouted into submission by a gaggle of offended professors. Her sin? Being right. Theirs? Feeling threatened by the truth. It costs something to learn something new that reveals the flaws in older ideas.

One scientist who didn't fall prey to this phenomenon was Louis Pasteur. He had the political acumen to make sure he had powerful friends when needed, he was a showman who used public demonstrations (thoroughly prepared beforehand) to publicize his ideas, and he was careful to tailor his presentations to make it seem like his discoveries came as flashes of insight, where in reality he labored long and hard upon them.

The author tells stories of others, including friends and acquaintances, who survived being right only because of more established mentors, and by finally "being right" in a sufficiently public way that could not be denied. Katalin (Kati) Karikó and Drew Weissman received the Nobel Prize in 2023 for working out the therapeutic use of mRNA agents, which led to the "vaccines" used during the Covid-19 pandemic. But Kati had rough going for many years, suffering abusive supervisors and disdainful department heads. Somehow, she plowed through, and collaborations such as that with Dr. Weissman kept her work going. Many others have been less fortunate. Alison left science, as have several others mentioned in the book.

Being right is not enough to ensure being received. Max Planck is known for saying that science proceeds one funeral at a time. My father used to speak of the "Moses Effect", meaning that it takes 40 years in the wilderness for a generation to die out so a new generation can make progress.

Semmelweis seems to have had no such advantages, and many disadvantages. He was not the only doctor to learn the value of chlorine-laced wash water for disinfection. But in his own hospital, he seems to have had the knack for presenting his findings in a way that didn't just challenge other doctors, including his supervisor, he actually indicted them along with himself for killing thousands of young mothers through ignorance.

Arthur C. Clarke's "first law of science" is, "When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong." The trouble is, the distinguished and elderly scientists usually stopped having good ideas half a lifetime ago and feel threatened by the next generation.

These days, it may seem we have moved beyond the times of Galileo, who had to stand before the Holy Office of the Inquisition for saying that Earth moves. Scientists these days don't have the rack or a team of archers to deal with mavericks. But they do have powerful weapons to destroy us anyway. Today, money runs science, in a way much more pervasive than ever before. The "old guard" controls the flow of money, which determines who can afford to do experiments, and who must find a different profession.

I think of two doctors I knew well. One, named Henry, was a radiation oncologist. He once said he could cure most cases of breast cancer, at lower cost than chemotherapy. However, most patients get steered toward chemo rather than radiation. When I asked why, he just rubbed two fingers together, the sign for "money". The other doctor, named Benjamin, is a friend I once asked about how thyroid issues affect fertility. He said, "One third of infertility cases are due to low thyroid, but it is the last thing tested, when it is tested at all." Of course I asked why, and he said, "Treating low thyroid is the cheapest remedy."

In the last chapter the author discusses possible remedies for the prejudice-dominated grant-awarding process. While he has some good ideas, including ideas that are being used on a small scale, he recognizes that government action would be needed to motivate widespread change. Given the huge pharmaceutical and medical lobbying that goes on, useful change is unlikely. I fear that Max Planck was only partly correct, because he said "one funeral at a time." It takes several.

I think of Ignaz Semmelweis and the other pilloried scientists as being like Jeremiah: never wrong; never believed.

Friday, July 24, 2026

The first Mars generation

 kw: book reviews, nonfiction, science, astronomy, astronomers, biographies, mars, social phenomena

In 1877, Mars and Earth had a "great opposition". The two planets were close together, just about 56 million km (35 million miles). The orbit of Mars is somewhat elliptical, so at "less favorable" oppositions, dates when Mars is directly outward from the Sun and high in our night sky at midnight, the distance can be as great as 102 million km (63 million miles). Astronomer Giovanni Schiaparelli took advantage of the great opposition to observe Mars nightly, for weeks. In addition to blotches and pale areas, he saw a few seemingly linear features, which he called canali, the Italian word meaning "channels".

The word canali does not refer to artificial waterways; other meanings are "troughs" and "gullies". Unfortunately for the next generation or two of the American and European public, when Schiaparelli's  work was translated into English, the translator chose to use the word "canals".

About seventeen years later, Percival Lowell, nearing the age of forty, having observed Mars in telescopes located in Boston and elsewhere, built his observatory near Flagstaff, on "Mars Hill". With the 24-inch diameter telescope he installed there, he watched Mars obsessively during every period of opposition. The drier, steadier air in Flagstaff enabled him to see the planet more clearly. Over time, he discerned numerous linear features, writing of them as "canals". He inferred that they were produced by intelligent Martians.

Lowell's articles, books, lectures, drawings and later photographs of Mars stirred a kind of Mars Mania for a generation, as described by David Baron in The Martians: The True Story of an Alien Craze that Captured Turn-of-the-Century America.

Percival Lowell was rich, driven, obsessive, and probably bipolar. He had earlier had a varied career, including being a kind of envoy for Korea and Japan. Once the observatory was completed, and he had released his book Mars, the planet and his theories about the Martians and their engineering abilities dominated his life and enthralled the public.

His public lectures and writings kept Mars Mania going for the rest of his life, in spite of opposition from roughly half of the scientific establishment. One particularly telling blow came from an experiment conducted by Walter Maunder, which became known as the "Small Boy Theory". Maunder began with maps of Mars produced by Schiaparelli and Lowell. He removed all the canals and replaced them by scattered dots or bits of riverine shapes. For each of several tests, such a doctored map was hung high on the wall at one end of a large classroom, and schoolboys were seated throughout the room. They were asked to copy the map as well as they could, without moving from their seats. Those closest to the front made the best facsimiles, of course. The farther back a boy sat, the more likely he was to add straight lines where dots and fragments seemed to run together in his vision.

Lowell never wavered from his view of a canal-riddled Mars. This image from page 62 shows one of his maps showing the "canals" and "oases" (dots) he drew. Just below it is an image I captured from Google Mars, taking in the approximately same view of the planet. The straight edges of some dark areas are artifacts of different camera views stitched together.

The scattered dots in the lower image are craters. I remember in 1965 when the Mariner 4 spacecraft sent us images of Mars that resembled a moonscape: loads of craters, and no canals. This was just a century after the Flagstaff Observatory was established.

Have you looked at clouds to see "cloud animals" and other fantasies? Various amorphous shapes can look like faces. There is a blotch in the abstract pattern in my shower that looks a little like a panther's head, only when I have my glasses off. This is called pareidolia. A roughly lined-up string of spots can look like a straight line when seen from a certain distance.

But what further affected Lowell as he aged was a bad case of confirmation bias. It's something we are all prone to: when we like an idea, we remember facts that support our view and discount those that don't.

At one point, Lowell spent some time looking at Venus. He produced the map in the upper part of this pair (from page 76). He was told that the "map" seemed to just reflect the blood vessels in his retina; he apparently agreed, and retracted the map. 

I've viewed Venus a number of times with various size telescopes. To a normal human eye, it is featureless, a blank white disk. However, if Lowell had lived a century later, and had a cataract operation, he might have seen features on the surface that are visible in ultraviolet light, particularly if he used a dark blue filter such as Cobalt glass. The lower image simulates such a view; I just "blued up" an ultraviolet photo of Venus. The natural lenses in our eyes are yellow, to filter out deep blue and UV light, which are hard to focus and tend to blur the vision. Cataract operation patients can see more UV than the rest of us.

Well, that would only be true before 1980. Since then, the plastic lenses that are inserted to replace the natural lens also filter out UV light. Oh, well, my hopes of getting my cataracts out and gaining UV vision are dashed!

Percival Lowell married at age 53. Eight years later, somewhat a fallen hero but still well remembered by the public that had been enthralled by his lectures, he passed away at age 61. When Clyde Tombaugh discovered Pluto in 1930 Lowell was still sufficiently famous that the planet was given the symbol  using Lowell's initials.

I have just skimmed over Lowell's life. I sympathize with his "neurasthenia", which was probably depression in the "low" phase of bipolar syndrome. I've been there. David Baron did an amazing amount of research to put this book together. The apparatus—source notes, bibliography, list of illustrations, and index—take up a quarter of the volume, almost 80 pages. Many other people who surrounded Lowell and the Mars phenomenon, including Nikola Tesla, Sir Arthur Conan Doyle, and Camille Flammarion, play their parts in this narrative. The fabric of these lives is a fascinating tapestry of the American and European societies of the thirty years surrounding the year 1900, when so much happened.

Why did I title this piece "The first Mars generation?" A new Mars generation has arisen, enthralled by the vision of Elon Musk, who wants to establish a colony on Mars with a million inhabitants. He hopes the first humans to reach mars will do so in the early or mid 2030's. Maybe it will work...

Saturday, February 21, 2026

Looking past old bones

 kw: book reviews, nonfiction, science, geology, paleontology, plants, evolution

Cyanobacteria, which were called "blue-green algae" when I was taking Freshman botany more than sixty years ago, arose about 2.7 billion years ago. The Earth started to become green. Before that it was primarily orange. The greening of Earth began in earnest once certain cyanobacteria became incorporated into the cells of an Archaean species to become chloroplasts in the first eukaryotic cells. Multicellularity, in the sense that among a bunch of cells that were sticking together, the cells began to have different functions, came about perhaps 1.5 billion years ago. By 1.2 billion years ago a proto-alga we call Bangiomorpha was the tallest plant in the shallows of the Precambrian ocean, being all of 2 mm tall, towering over micron-sized prokaryotes.

Bangiomorpha features in the first chapter of When the Earth was Green: Plants, Animals, and Evolution's Greatest Romance by geologist Riley Black. The chapter is titled "Sex in the Shallows" because it is pretty certain that Bangiomorpha was among the first organisms to reproduce via sexual differentiation of gametes and gamete fusion.

Side note, not related to the content of the book: The preference in nature to use DNA rather than RNA for long-term storage and retrieval of genetic information is based on its stability. RNA copying is much more prone to error, and the lack of pairing of RNA strands makes an "RNA world" very fragile. However, RNA is essential for helping DNA make copies of itself, and for translating sections of DNA into proteins. The fact that the biosphere was extremely slow to change during the first billion years after life began indicates that DNA is "too slow"! The mix-and-match processes of meiosis and gametogenesis sped things up appropriately, so that complex life could arise before the Sun burned out (not that "nature" had any idea it had such a deadline). Sex combines a level of stability much greater than an RNA basis allows, while also providing mechanisms for making changes more rapidly, particularly when small populations are isolated under adverse conditions. As you might imagine, biological theorists are still arguing strenuously about the pace of evolutionary change at various levels.

Back to the book: The fifteen chapters each tell a story of a particular organism or ecosystem, focusing on the plants. Most of paleontology is "shells and bones". Having done my time clambering over desert landscapes all over North America—as Riley Black is still doing, lucky kid!—I relate strongly to the tendency to focus on the hard bits. It is easy to climb a cliff that was a marine reef in the Pennsylvanian Era and snatch up brachiopods, bryozoans, clams, snails, and corals. The plants that accompanied them are simply not in evidence; they don't fossilize well in the gritty sands that surround the structures of the reef. And why collect fossils in deserts? I live in Delaware now, and most rocks containing fossils are buried under tens of feet of soil. In Nevada, there are lots of rocks right at the surface.

Some of the chapters tell stories that feature sundry animals, retaining the emphasis on the plants they lived among, and often upon. For example, Chapter 13, "Far from the Tree" has a proto-hyena watching two monkeys squabble on the branch of a tree in late Miocene Ethiopia, hoping one will fall. The tree is the "hero" of the story, along with the effects tree dwelling had on the morphology of the little primates. The focus of the chapter is the gradual spread of grasses as the forests retreat. 

By the way, it is stated that grasses have C3 photosynthesis, making them more efficient than trees at turning CO2 and water into carbohydrates. This is an error. Grasses are the primary C4 plants, while most shrubs and trees use the older C3 photosystem. I don't know if this is a typo; it should have been caught by the copy editor at very least (The author had a copy editor, who is named in the Acknowledgements). Anyway, to my point: Prior to the evolution of C4 photosynthesis, CO2 content of the atmosphere was nearly always between 500 ppm and 2,000 ppm. C3 plants thrive best with at least 500 ppm. C4 plants can draw down CO2 below 100 ppm, at which point most trees won't grow at all. So, you folks out there that want to grow stuff to draw down CO2, use grasses, not trees. Even at today's CO2 level of 440 ppm, the trees are struggling.

My favorite chapter is 3, "The Forest Primeval", in which the author lyrically describes aspects of life in the Carboniferous Era (as it is called in Europe; in North America this era is divided into the Mississippian and Pennsylvanian Eras).

This image I generated using Seedream V4.5 in OpenArt is not as densely packed with trees as I wanted, but it shows the alienness of the treelike species that existed at the time. Of course, I had to include an eagle-sized dragonfly. The rapid profusion of plants and their equally rapid burial, which formed our coal beds, led to a very high level of atmospheric oxygen. As the author points out, the larva of the dragonfly needed to be larger to reduce oxygen toxicity. Yet the extra oxygen also fueled the energy needed for the adult to thrive at its meter-sized length.

Had I been the publisher's editor, I might have amended the book's title to just The Earth was Green. This image of the Blue Ridge in Tennessee, from a panorama by the National Park Service, shows that Earth is very green even today:


Riley Black is a trans woman, who put the pronouns "she/they" in the author bio. Since she is at least halfway through a full physical transition, I'm willing to say "she". "They"? Not so much. I care about singular and plural. Her pronoun confusion extends to the grammar of the book, where it is applied to the creatures. Sentences with wording such as, "Now that the monkey can reach the fruit, they can…" are simply solecisms. The common usage is "it can…", which is at least genderless. Similar grammatical errors are found numerous times per chapter. It is sad. Apparently her copy editor shares her grammatical mis-education.

Ms Black's writing is lyrical and enjoyable. She has published several earlier books, and I understand all are popular. And I envy her access to so many prime fossil localities!

One last quibble: In the first chapter, describing how DNA data are mutated, the analogy of a copy of a copy of a copy in a photocopier is used. It's a very bad analogy. The successive copies gradually fuzz into meaninglessness. No new letters appear. In DNA, every "word" is exactly three letters. Every possible combination is meaningful. A DNA copy error doesn't make any fuzz, it exchanges one letter for another, or it may even add or delete a letter, causing a frame shift (frame shifts are fatal flaws).

Sunday, February 08, 2026

Dominance of the spineless

 kw: book reviews, nonfiction, science, oceanography, biology, invertebrates, medicine

Behold a gallery of sponge animals. They headline The Ocean's Menagerie: How Earth's Strangest Creatures Reshape the Rules of Life by Drew Harvell.

Considering the matter for a moment, I concluded that the word "reshape" in the title ought to be "reveal." I suppose the publisher thought the title as it is makes better clickbait.

The thousands (almost 10,000 so far) species of sponge comprise the phylum Porifera. Their shapes and sizes are so variable, that pores are the only consistent feature. Brainless, apparently without nervous systems, they are remarkably successful predators. Most consume plankton (little floating things), but some grow over and consume coral animals, and some have inner chambers with other critters such as shrimp living inside. The shrimp gets a safe home, and the sponge eats the leftovers the shrimp drops. Being stationary, sponges need good defenses against predation and against diseases caused by bacteria, fungi and viruses. Dr. Harvell tells us that they have the most multifarious immune system of all animals. Her particular interest is figuring out how their various chemical defenses work, and which ones might lead to medical advances for humans. She writes, "…I call the capability to produce potent biologically active chemicals a sponge superpower." Sponge research is likely to lead to either better antibiotics, or to new alternatives to antibiotics, for example.

This image shows several corals along with a variety of sea anemones, which are related to corals. Both are members of the phylum Cnidaria, which also includes jellyfish (called "jellies" by scientists because they most definitely aren't fish). The phylum contains more than 11,000 species. Though they are  brainless, they have simple nervous systems that coordinate their movements.

The basic body plan is a radially-symmetric, columnar tube with only one opening (a combined mouth-anus) surrounded by stinging tentacles. Sea anemones are larger and solitary, while corals are colonial and build skeletons; the stony corals build mineral skeletons that form the backbones of reefs.

Stony corals are the subject of the second chapter (of 8). They are considered a "canary in the coal mine" related to ocean acidification. Later in the book we find that the pH of the ocean is presently very near 8.0; elsewhere I read values ranging to 8.05. A century ago ocean pH was about 8.15

Sidebar on pH: It is a logarithm, the negative logarithm of hydrogen ion concentration in water. Pure, distilled water has pH of 7, which means that the concentration is 10-7, or one ten-millionth, or one hydrogen ion per ten million molecules of water (pH=7 is called "Neutral"). Thus a pH of 8 means one hundred-millionth. Putting these on a linear scale, adjusted with 1 meaning one per billion (pH=9) and 10 meaning pH=8, pH=8.05 converts to 8.9 and pH=8.15 converts to 7.08. Dividing the linear values, 8.15/7.08 = 1.15, which means that "acidity" is 15% greater at pH=8.05. Both these values are slightly alkaline, one more than the other.

What does 15% extra acidity mean to a coral (or any other ocean creature that uses calcite for its skeleton or shell)? Acid dissolves calcite, which doesn't dissolve when pH is 7 or larger. Acids have lower pH. For example, the pH of orange juice is about 4, and lemon juice pH is less than 3 (sour! You can taste pH). In sum, getting calcite to precipitate out of sea water is easier, and takes less chemical energy, when the water is a little alkaline. It takes a coral more energy to form its calcite skeleton at pH=8.05, compared to 8.15. Do note that fears of "shells dissolving" in the oceans any time in the near future are groundless. However, corals and shelled animals are having a little harder time forming their skeletons and shells.

On to Chapter 3, about sea fans and other gorgonians. These are also in the phylum Cnidaria, and are often called "soft corals" because they don't form rocky skeletons, using chiton or similar biopolymers instead. The word "gorgonian" refers to the Gorgon of mythology, who had snakes instead of hair on her head. An early biologist thought that these animals looked a little like that.

Collecting part of one of these is easier than collecting a stony coral: you don't need a hammer and chisel! And collecting is what the author did, of many of these creatures. Soft corals have immune defenses nearly as potent and various as sponges do, plus stinging cells like other cnidarians. Usually, the stinging cells, or nematocysts, not only immobilize prey, they also fend off most predators. Most. That word introduces the fourth chapter.

The term "sea slug" is rather ugly, because most of us know slugs in the garden as voracious pests, with slippery grayish bodies that offend most folks. I like the term "Nudibranch" better; it means "naked gills". As this illustration shows, these oceangoing mollusks are often beautiful. Being mollusks, they are members of the second largest phylum, Mollusca, with at least 100,000 species, and perhaps a million or more—we know so little about the ocean… Mollusks have a pass-through body, with both mouth and anus, plus a brain and nervous system. 

Nudibranchs' bright colors warn of a darker side to them. Many are venomous, but not in the way a snake or spider is. Many nudibranchs eat corals and other cnidarians, and they have an astounding biochemical trick: they can capture the nematocysts of their prey without setting them off and incorporate them into their own frilly tissues. Brushing up against one is like encountering a jellyfish and can sometimes be life-threatening.

The giant clam, subject of Chapter 5, is a quite different kind of mollusk, with a different superpower. They channel light and even shift its color, to "feed" symbiotic algae that provide much of the clam's nourishment.

The bright colors of their mantles are a combination of filtered light and fluorescence. Ultraviolet and violet-blue light in particular are useless for inducing photosynthesis. Fluorescent chemicals convert some of these "blue and ultra-blue" colors to colors the algae can use. In addition, the algae are arranged in small physical structures that stack them in ways that increase their overall efficiency. We have a lot to learn from clams! On a side note, we learn that these big clams cannot close their shell all the way. Old rumors about divers being trapped by giant clams are bunk.

One more group of mollusks fills Chapter 6. The skin of an octopus is possibly the most complex organ in the animal kingdom. This image shows an octopus most of the way through a rapid transition into looking like a lumpy rock. A careful look will reveal an eye, and further down, a few of the suckers that haven't yet been tucked under.

Octopuses, cuttlefish, and squids can change color, not just wholesale, but in patterns. The first two can also raise lumps, bumps and spikes in their skin to produce all kinds of shapes. A moment before this photo was taken, the octopus had smooth orange-red skin. It changed so fast that it seemed to vanish before the diver's eyes. Single frames from the video showed that the entire transformation took about a quarter second (7 or 8 frames in a 30-fps video). Great numbers of tiny muscles surround chromatocytes (color organs the size of a poppy seed) and sections of skin (to shift from flat to bumpy or spiky), under direct nerve control. Perhaps that is why an octopus or cuttlefish has nine brains. Lots of logistics going on!

Back to Cnidaria for Chapter 7: Jellies and their light shows. I have only seen these animals at the surface. On a couple of occasions my friends and I pulled dozens of 2-foot-wide jellies out of the surf at Huntington Beach in California, to make swimming safer. If you dive at night, you are more likely to see the light show. Not only jellies, but many other soft-bodies sea critters make their own light, or have captured special bacteria that do it for them. This amazing medusa has several colors of bioluminescence. It was photographed by its own light.

How poor is our land-borne experience! We have only fireflies and glowworms (certain female fireflies) and a number of other beetles to light up an evening, and a few species of glowing mushrooms. In the ocean, 90% of species produce light. Naturally, scientists are scurrying to learn their secrets. One is very useful already: green fluorescent protein (GFP), derived from a jelly. DNA to produce it is easy to splice into various parts of other animals' genomes, producing mice that glow green, or small fish with certain organs that glow with varying brightness as metabolism waxes and wanes.

Another phylum shows up in the last chapter, Echinodermata, the "spiny skins". Sea stars (colloquially, starfish) are not quite radially symmetric, as the Cnidaria are. There is a respiratory port off-center on top, making them bilaterally symmetrical, just barely.

This gallery shows 13 species of sea star, and three related echinoderms. The phylum contains more than 7,500 species so far known, while we have fossils of 13,000 extinct species. All are predatory.

This chapter focuses first on an experiment in removing sea stars from a section of seacoast. The area became overrun by mussels, which grew to the size of footballs. Where sea stars were present, there were still lots of mussels, but also areas where many other animals could settle, which greatly increased biodiversity.

More recently, there was a "starfish pandemic", and nearly all the common ochre stars along the west coast of the US and into Canada died, plus just as many "sun stars", a deep-water species with 24 arms. Over time, natural selection did its work and the numbers of ochre stars began to recover, but not, at the date of writing, the sun stars. The author and others are doing captive breeding to develop a resistant variety of sun star, in hopes of repopulating the deep coastal plain. Why, you might ask? Sun stars prey on sea urchins. If unchecked, sea urchins eat all the kelp. Kelp forests protect many species of fish and other pelagic (midwater) animals, including commercial species. Sun stars in deeper water and ochre stars in tidal areas are keystone predators: their presence controls the biodiversity of entire areas.

Throughout the book the author complains of the effects of climatic warming and ocean acidification that are based on increasing carbon dioxide in the atmosphere. In the ocean areas she frequents, the effects are visible. She calls it a Gut Punch. Her Epilogue is a long plea for more rational approaches to management of the ocean. While I agree with her on one level, I find it sad that we, as a species, find the need to "manage" 3/4 of the planet's surface. What we really need is to manage ourselves, but the lesson of the Bible, along with most other religious texts, is that humans excel at mismanagement, and any god you may imagine has a hard time keeping us in check. 

For context: The God of the Bible spent two millennia dealing with one family, the descendants of Abraham, to finally rid them of their tendency toward idolatry. He has spent the two millennia since then dealing with the spiritual descendants of Abraham, that is, the Christians, and has yet to rid them (us) of their (our) tendency to divide (there are more than 40,000 "denominations"), primarily over opinions, which are our modern idols. Mismanagement of the human soul is the source of mismanagement of planet Earth. This is why we need a Savior.

Monday, December 15, 2025

How to not be seen

 kw: book reviews, nonfiction, science, optics, visibility, invisibility

In a video you may have seen (watch it here before continuing; spoiler below),

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…titled "Selective Attention Test", you are asked to keep careful watch on certain people throwing basketballs.

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…Several seconds in, someone wearing a gorilla suit walks into the middle of the action, turns to the camera, beats its chest, then walks back out of the scene. When this is shown to people who've never heard of it, about half report seeing the "gorilla", and half didn't see it. 

This is called Inattentional Blindness. It is used by stage magicians, whose actions and talk in the early part of a performance direct the audience's attention away from what is happening right in front of them. A magician can't be content with misdirecting half of the audience; the goal is 100%. This is often achieved!

But what if someone wants to vanish from plain sight, without benefit of a flash of fire or smoke (the usual prop for a vanishing act)? Optical science researcher Gregory J. Gbur might have something to say about that in his book Invisibility: The History and Science of How Not to be Seen.

Much of the history Dr. Gbur draws upon is found in science fiction. It seems that every scientific discovery about optics and related fields was fodder for science fiction writers to imagine how someone could be made invisible. This cover image from a February 1921 issue of Science and Invention (edited and mostly written by Hugo Gernsback, later to write lots of science fiction and edit Amazing Stories) shows the rays from something similar to an X-ray machine making part of this woman invisible.

I looked for this cover image online and found an archive of S&I issues. However, the issues were apparently produced with various covers for different regions, and the version in the archive had a cover touting a different application of X-rays. However, the article on page 1074, referred to in the cover shown above, does discuss whether X-rays or something like them can be used to provide invisibility, and also shows another way that structures inside the body may be seen.

Here the "transparascope" makes certain tissues transparent, allowing the viewing of others. IRL, the development of CT scanning and MRI scanning, fifty-odd years later, were required to achieve such views. The invisibility beam of the cover image has so far proved elusive.

Invisibility sits in the broader realm of "how not to be seen." The book shows in detail that the technologies that have been developed to hide or cloak objects can only work perfectly over very narrow ranges of light wavelength (and by analogy, waves in water and other media), and usually a narrow range of viewing angle. Is perfection needed? That depends…

In the late 1960's I worked for a defense contracting company, mainly as an optical technician. I was loaned to a related project as an experimental subject. The team was gathering data on the limits of human vision, detecting the contrast between a lighted object in the sky (an aircraft) and the sky. This was the Vietnam War era. 

The experimental setup was a room with one wall covered with a screen on which versions of "sky blue" were projected. At the center was a hole and various targets were set in this hole. They simulated the look of a dark or darkish object in the sky, and each target had several lighted spots, little lamps. The lamps' color and brightness could be adjusted. I was instructed to tell what I could see. The first day I was there, the background target was black, and the lamps were small and bright. The targets had differing numbers of lamps and their brightness would be adjusted to reduce the visibility of the overall target. This tested acuteness of vision; how many lamps on a certain size target would "fuzz together" and seem to illuminate its entire area? 

For most people, the "fuzz" angle is 1/60th of a degree. When you look up at a Boeing 737 at 30,000 ft elevation, its length of about 130 feet means it subtends and angle of about 1/4 degree. It would take two rows of 25 lamps along the fuselage, and at least 10 lamps, or 10 pairs of lamps, along each wing, to counter-illuminate it and reduce its visibility. That's a lot. A B-52 bomber is 20 feet longer and its engines are huge, like misplaced chucks of fuselage.

On another day, the target's background color was a blue color somewhat darker than the "sky". The target had the optimum size and spacing of lamps to seem of more-or-less uniform brightness, and the brightness and color of the lamps were varied. This tested our color acuity; how far could the colorimetry of the target-lamp combination vary to remain invisible or minimally visible?

This image simulates the second kind of target-lamp combination If you look at this image from a sufficient distance, the simulated target will nearly disappear, or for you it may vanish completely. This works best if you either take off your glasses or look through reading lenses, to defocus the image.

The average color and brightness of the simulated target are a close match to the surrounding sky-blue color. Thus, if an aircraft's belly is painted a medium blue, and a sufficient number of lamps are mounted on it and controlled by an upward-looking system, it can seem to vanish against the sky as long as it is high enough that the angular distances between the lamps is smaller than the circle of confusion (1/60th degree) of the eyes of an observer below.

This set of letter-targets is similar to a different test. Each letter has a little different color and brightness than the "sky". The 5 letters here make up the word "ROAST", but are not in order. For this test the sky color would be adjusted to see which letters were least and most visible. In both panels you will probably see three or four letters, but one or two that are not seen in one panel will be seen in the other.

In the end, it was all for nought. The sky is too variable, and human vision is also variable. There are three kinds of color blindness, and six kinds of "anomalous color vision"; any of these renders visible a target that "normal" eyes cannot see. It's kind of the opposite of those color-blindness tests with pastel "bubbles" that show the letter K to "normies" but the letter G to most color blind people. Also, wearing polarized glasses changes the perceived color of the sky, and tilting your head makes a dramatic difference in the color. Anyone with shades on would see the aircraft easily.

A further drawback of these tests was that no Asians' eyes were tested. In my regular job at the time, we were developing an infrared light source that Asians could not see. The near-infrared lamps used for night vision goggles and SniperScopes were invisible to Anglos, but quite visible to the Vietnamese. Several American snipers lost their lives when they turned on their SniperScope and a bullet came back instantly. What eventually worked was not a different light source but hypersensitive image amplification, the "starlight scope".

My wife is Asian. Certain items that look green to me she tells me are blue. Away from the green-blue boundary, she and I agree on the colors of objects.

The later chapters of Invisibility describe experiments and simulations that could lead to effective cloaking. There is even an appendix that shows a home tinkerer how to make a couple of kinds of visual cloaks that work in at least one direction. Full-surround cloaking is still out of reach, but who knows?

This book earns my "fun book of the year" award. Well written and very informative.

Saturday, December 13, 2025

Nails in the coffin of dark energy?

 kw: science, cosmology, dark energy, supernovae, supernovas, type ia supernova, metallicity

INTRODUCTION

The ΛCDM model of the Universe was proposed after two research groups (led by Adam G. Reiss and Saul Perlmutter) studied certain supernovae. "Λ" (Greek lambda) refers to the cosmological constant, first proposed by Einstein, that describes the expansion of spacetime. The research teams concluded that spacetime was not just expanding, but expanding at an increasing rate. This is called "cosmic acceleration." Their key observation was that distant Type Ia supernovae are fainter than expected. This soon led to the hypothesis that 75% of the energy content of the Universe is "dark energy", which is driving and accelerating the expansion.

When I first read about "dark energy" more than 25 years ago I thought, "How can they be sure that these supernovae are truly 'standard candles' over the full range of ages represented, more than ten billion years?" I soon considered, "Is the brightness of a Type Ia supernova affected by the metallicity of the exploding star?" and "Is it worth positing a huge increase in the energy of the Universe?" From that day until now I have considered dark energy to be the second-silliest hypothesis in cosmology (I may deal with the silliest one on another occasion).

On December 10, 2025, an article appeared that has me very excited: "99.9999999% Certainty: Astronomers Confirm a Discovery with Far-Reaching Consequences for the Universe’s Fate", written by Arezki Amiri. In the article, this figure demonstrates that I was on the right track. The caption reads, "Correlation between SN Ia Hubble residuals and host-galaxy population age using updated age measurements. Both the low-redshift R19 sample and the broader G11 sample show a consistent trend: older hosts produce brighter SNe Ia after standardization, confirming the universality of the age bias. Credit: Chung et al. 2025"

It reveals a correlation between the brightness of a Type Ia supernova and the age of its host galaxy. Galactic age is related to the average metallicity of the stars that make it up. Thus, more distant Type Ia supernovae can be expected to be fainter than closer ones, because more distant galaxies are seen when they were younger, and consequently had lower metallicity. This all requires a bit of explanation.

WHAT IS METALLICITY?

Eighty percent of the naturally-occurring chemical elements are metals. That means they conduct electricity. Astronomers, for convenience, call all elements other than hydrogen (H) and helium (He) "metals". The very early Universe consisted almost entirely of H and He, with a tiny bit of lithium (Li), element #3, the lightest metal. The first stars to form were not like any of the stars we see in our sky. They were composed of 3/4 hydrogen by weight, and 1/4 helium. The spectral emission lines of H and He are sparse and not strong. Thus, the primary way for such a star to shine is almost strictly thermal radiation from a "surface" that has low emissivity.

[Insert Fig2 and add a caption] By contrast, a star like the Sun, which contains 1.39% "metals", has many, many spectral lines emitted by these elements, even as the same elements in the outer photosphere absorb the same wavelengths. On balance, this increases the effective emissivity of the Sun's "surface" and allows it to radiate light more efficiently. The figure below shows the spectra of several stars. Note in particular the lower three spectra. These are metal-poor stars, and few elemental absorption lines are visible (The M4.5 star's spectrum shows mainly molecular absorption lines and bands). However, even such metal-poor stars, with less than 1/10th or 1/100th as much metals content as the Sun, are very metal-rich compared to the very first stars, which were metal-free.

Spectra of stars of different spectral types. The Sun is a G2 star, with a spectrum similar to the line labeled "G0".

One consequence of this is that a metal-poor star of the same size and temperature as the Sun isn't as bright. It produces less energy. Another consequence, for the first stars, is that they had to be very massive, more than 50-100 times as massive as the Sun, because it was difficult for smaller gas clouds to shed radiant heat and collapse into stars. Such primordial supergiant stars burned out fast and either exploded as supernovae of Type II or collapsed directly into black holes.

THE TWO MAIN TYPES OF SUPERNOVAE

1) Type I, little or no H in the spectrum

A star similar to the Sun cannot become a supernova. It fuses hydrogen into helium until about half of its hydrogen is gone. Then its core shrinks and heats up until helium begins to fuse to carbon. While doing so, it grows to be a red giant and gradually sheds the remaining hydrogen as "red giant stellar wind". When the helium runs out, the fusion engine shuts off and the star shrinks to a white dwarf composed mainly of carbon, a sphere about 1% of the star's original size, containing about half the original mass. For an isolated star like the Sun, that is that.

However, most stars have one or more co-orbital companion stars. For any pair of co-orbiting stars, at some point the heavier star becomes a red giant and then a white dwarf. If the orbit is close enough some of the material shed by the red giant will be added to the companion star, which will increase its mass and shorten its life. When it becomes a red giant in turn, its red giant stellar wind will add material to the white dwarf. The figure shows what this might look like.

White dwarfs are very dense, but are prevented from collapsing further by electron degeneracy pressure. This pressure is capable of resisting collapse for a white dwarf with less than 1.44 solar masses (1.44 Ms). That is almost three times as massive a the white dwarf that our Sun is expected to produce in about six billion more years. It takes a much larger star to produce a white dwarf with a mass greater than 1.4 Ms, one that began with about 8 Ms. Such a star can produce more elements before fusion ceases: C fuses to O (oxygen), O fuses to neon (Ne), and so on through Na (sodium) to Mg (magnesium). The white dwarf thus formed will be composed primarily of oxygen, with significant amounts of Ne and Mg. Such a stellar remnant is called an ONeMg white dwarf. Naturally it has more metals present than the original star did when it was formed, but less than a white dwarf formed from a higher-metallicity star.

Now consider a white dwarf with a mass a little greater than 1.4 Ms, with a companion star that is shedding mass, much of which spirals to the white dwarf, as the figure illustrates. When the white dwarf grows to 1.44 Ms, which is called the Chandrasekhar Limit, it will collapse as a powerful Type Ia supernova.

There are two other subtypes, Ib and Ic, that form by different mechanisms. While they are also no-H supernovae, there are differences in their spectra and light curve that distinguish them from Type Ia, so we don't need to consider them further.

2) Type II, strong H in the spectrum

Type II supernovae are important because they provide most of the metals in the Universe. They occur when a star greater than 10 Ms runs out of fusion fuel. It takes a star with 10 Ms to produce elements beyond Mg, from Si (silicon) to Fe (iron). Fe is the heaviest element that can be produced by fusion. These heavy stars experience direct core collapse to a neutron star, with most of the star rebounding from the core as a Type II supernova. During this blast, the extreme environment produces elements heavier than Fe also. (Stars that are much heavier can collapse directly to become a black hole.)

EVOLUTION OF UNIVERSAL METALLICITY

At the time the first stars formed, the Universe was metal-free. It took a few hundred million years for a few generations of supernovae to add newly-formed metals, such that the first galaxies were formed from very-low-metal stars and low metal stars. Even with very-low to low metallicity, smaller stars could form. Since that time, most stars have been Sun-size and smaller, though stars can still form with masses up to about 50 Ms.

Stars of these early generations smaller than about 0.75 Ms are still with us, having a "main sequence lifetime" exceeding 15 million years. I can't get into the topic of the main sequence here. We're going in a different direction.

Stars of the Sun's mass and heavier have progressively shorter lifetimes. Over time, the metallicity of the Universe has steadily increased. That means that the "young" galaxies discussed in the Daily Galaxy article (and the journal article it references) are more distant, were formed at earlier times in the Universe, and thus tend to have lower metallicity.

LOWER METALLICITY MEANS LOWER BRIGHTNESS

This leads directly to my conclusion. A Type Ia supernova erupts when a white dwarf, whatever its composition, exceeds the Chandrasekhar Limit of 1.44 Ms. This has made them attractive as "standard candles" for probing the distant Universe. However, they are not so "standard" as we have been led to believe.

Consider two white dwarfs that have the same mass, say 1.439 Ms, but different compositions. One is composed of C or C+O, with very low amounts of metallic elements. The other has a composition more like stars in the solar neighborhood, with 1% metals or more. As seen with stars, more metals lead to more brightness, for a star of a given mass. Similarly, when these two white dwarfs reach 1.44 Ms and explode, the one with more metals will be brighter than the other.

The final question to be answered: Is this effect sufficient to eliminate all of the faint-early-supernova trend that led to the hypothesis of dark energy in the first place? The headline to the article indicates that the answer is Yes. A resounding yes, with a probability of 99.9999999%. That's seven nines after the decimal. That corresponds to a 6.5-sigma result, where 5 sigma or larger is termed "near certainty".

The article notes that plans are in the works to use a much larger sample of 20,000 supernovae to test this result. I expect it to confirm it. The author also suggests that perhaps Λ is variable and decreasing. My conclusion is that dark energy does not exist at all. Gravity has free reign in the Universe, and is gradually slowing down the expansion that began with the Big Bang (or perhaps Inflation if that actually occurred).

That's my take. No Dark Energy. Not now, not ever.

Sunday, November 09, 2025

Tied for the oldest sense

 kw: book reviews, nonfiction, science, olfaction, nose, sense of smell

It is fascinating to watch a motile bacterium such as E. coli in motion. It trundles along, its rear-mounted flagella spinning to propel it in a mostly straight line. If it bumps into something it will back up some distance, tumble, and then move off in a new direction. Frequently, after a short distance, it may reverse course or tumble again to pick a new direction.

The latter action hints at what is going on. How does it pick a direction to go; what is it trying to reach? Of course, like all living things, it is searching for food. It is following a chemical gradient by sensing a chemical of interest in the water around it. If, as it moves along, it senses a stronger concentration, it keeps moving. If the concentration is decreasing it reverses course or tumbles to try a new direction. Its chemical sense can be called either "taste" or "smell" and is one of the two oldest senses. The other is touch. Bumping into something, or alternatively, approaching closely enough for cilia on the cell to touch the something, coupled with the chemical sense telling it, "this isn't what you are looking for," triggers actions such as backing up and/or tumbling. Touch is the other "oldest sense." The two seem to go together, and they work together to guide the cell to a possible source of food.

Strictly speaking, smell is thought to relate to chemical cues carried in the air, so the bacterium, being in a watery medium, must be using taste rather than smell. But at the most basic level these are actually the same. Chemical substances that are smelled first enter a watery layer over the sensory nerves, where they are detected.

For air-dwelling creatures, smell is a more long-range sense. Chemical substances travel through the air faster than they do through water, although both aerial and fluid currents can bring them from far away. But diffusion in still air is faster than in still water. Furthermore, when two senses work together, smell precedes touch, while taste follows contact.

The title of Jonas Olofsson's book, The Forgotten Sense: The New Science of Smell and the Extraordinary Power of the Nose led me to think, "Why didn't he call it The Neglected Sense?" No matter. He reveals the neglect that smelling has undergone through the centuries since it was placed by Aristotle at the bottom of the list of useful senses, an error compounded when Paul Broca divided animals into "osmatic" and "anosmatic": those like the dog for which smell was primary and those like humans (he thought) for whom smell was definitely not worth much. I guess that neither Broca or old Ari stopped to consider how he would detect a bad lot of wine or olive oil if he plugged his nose. Tasting without smelling could be a risky business!

I was most fascinated by an analysis to which the author refers, "Human and Animal Olfactory Capabilities Compared," by Matthias Laska in the 2017 Springer Handbook of Odor. Humans and a number of medium-sized and smaller animals were tested for their sensitivity to a few dozen scented substances. Animals tested included rats, dogs, vampire bats, a couple of monkey species…twenty species in all. The only animal with a nose more sensitive than ours was the dog!

Earlier studies that compared the size of an animal's olfactory bulbs to its brain were misleading because it is the absolute size of the bulb that matters. The roughly 60 mm3 volume of human olfactory bulbs is a tiny fraction of the brain's volume, about 1/20,000th. In relative terms, the olfactory bulb of a mouse is enormous, about 1/16th of the total brain. However, its actual size is less than half that for a human: 25 mm3. An ordinary dog (not the tiny breeds or pug-nosed ones) has an olfactory bulb six times larger than a human, which gives it a huge advantage, as was shown clearly by the sensitivity tests. I wonder if they could give a similar test to an elephant, with an olfactory bulb volume of 11,000 mm3 ?

Technical issues aside, a big section of the book relates the emotional effects that smells can mediate, such as a whiff of salty air evoking a favorite memory of a seaside vacation, or the comfy aroma of a morning coffee and bowl of blueberries. 

This also introduces the subject of smell gone wrong: COVID-19 introduced millions around the world to a life without smells, at least temporarily. An interesting consequence of the sudden loss of smell for many people was that they began to wonder how they could tell if their own smell was offensive to others! Another was the loss of interest in food, because most of what we call the taste of many foods is actually a combination of smell and taste. We can taste but five qualities: sweet, salt, savory (umami), sour, and bitter; we can smell thousands or hundreds of thousands of different qualities. So many that we can seldom describe any of them to someone else.

Loss of smell is called anosmia. In some ways, a distorted sense of smell, parosmia, can be even worse. Imagine one day finding that your morning cuppa smells like rotting onions! This can also be caused by viral infections, but there are other causes, including a hard bump on the head. Some people with parosmia can't stand to eat favorite foods, though some are able to eat enough to stay healthy by putting on a nose clip. There is a long section describing ways of desensitizing and retraining the sense of smell. Sadly none of the methods is effective in all cases, but it can be a lifesaver for many.

A side note: There is a reversible distortion of taste I have experienced, caused by an Asian spice called Tiger Claw, related to Star Anise. The seed pods are used whole to flavor soup. They aren't supposed to be ingested. Biting into one causes a shift of taste, such that water tastes like battery acid and nothing seems edible; it lasts several hours. I have numerous Chinese friends, and I wound up mostly fasting during a potluck lunch…

The author is a scientist of the sense of smell. He first wrote the book in Swedish, then translated it into English himself. His and his colleagues' work just might elevate our understanding of the sense of smell, from a "neglected" sense to one that is equally essential. And in time perhaps we'll attain added vocabulary to help us describe our favorite (or otherwise) aromas.

Thursday, October 16, 2025

Finding Rex

 kw: book reviews, nonfiction, science, paleontology, biographies, dinosaurs, t rex, tyrannosaurus rex

The last summer that I was a geology student I spent six weeks in an area above Lee Vining in the Sierras. Midway through, in the early afternoon I was resting near a pond when several backpackers came by, hiking toward a wilderness area another mile along the trail. I asked them how long they would be there. One said, "A week. How long have you been here?" I answered, "Three weeks." "Wow! That's neat," another one answered. I grinned ruefully and said, "Not really." I was already getting tired of tenting. Of course, since part of my daily routine was gathering rocks and hauling 10-20 pounds of them back to base camp for identification, I suppose I wasn't having quite as much fun as the average tourist. By the end of the summer I was pretty clear that I wasn't cut out for a job that required lots of field work.

Reading The Monster's Bones: The Discovery of T. Rex and How it Shook Our World by David K. Randall, I could only admire the grit of Barnum Brown. To this day, roughly half of the dinosaurs and early mammals on display at the American Museum of Natural History in New York City are specimens he collected. In addition to an iron constitution, he had a quick mind and had learned to recognize the kinds of geological deposits most likely to contain great fossils. He had also learned enough anatomy to make a good guess as to what animal a new bone belonged to.

While Barnum Brown collected on most of the continents, his main stomping ground was the great fossil beds of north-central United States. This was the area made famous by the "bone wars" of Professors Marsh and Cope, from 1877 to 1982. These rivals went broke trying to outdo each other as they collected, and described, species after species of large vertebrate fossils. In the end, the biggest and baddest dinosaur of all escaped their grasp. Brown found the first specimen of Tyrannosaurus rex in 1902, and for some years, during which he found a few more, he was the only collector to find any.

The book is largely a biography of Barnum Brown, who was named for P.T. Barnum almost on a whim, because the circus was in town. The author details his "life and hard times" and the resulting drive that motivated him to seek solace in the wilderness. Yet he wasn't antisocial, as so many "mountain men" are. In addition to great strength and persistence and lively intelligence, he could be intensely social, the kind of guy who is the life of the party, whatever party he happens across. This enabled him to befriend ranchers and farmers in the field and to maintain a, if not good, at least useful working relationship with the notoriously prickly director of the American Museum, Henry Fairfield Osborne. It greased many a relationship necessary to get access and tips to the best bone deposits. Brown lived just days short of ninety years.

Rather than focus on Barnum Brown, I find most interesting the social changes in attitudes toward dinosaurs that resulted from the discovery of T. rex. All the large dinosaurs found previously were herbivores such as the familiar Brontosaurus and Diplodocus and duckbills such as Hadrosaurus. They were portrayed as overgrown cows, brainless, plodding beasts that had to move about half submerged in swamps to buoy up their enormous bulk. When the first Triceratops was described in 1889 by Charles O. Marsh, not many wondered what the great horns were needed for. Then when the first tyrannosaur was discovered by Brown in 1902, it soon became clear that those horns were sorely needed! Public interest was piqued, and as "tyrant king" specimens or replicas were displayed in a growing number of museums, museum attendance boomed.

T. rex is still the most popular dinosaur. The proliferation of celebrity knockoffs such as Barney and the popularity of tyrannosaur suits, used for all sorts of pranks, has made this terrifying beast almost a cuddly member of the household. But I'm sure I wouldn't want to stumble across this picnic in a nearby forest! (Image generated with the Flux1.Kontext engine in Leonardo AI.)

I'm a six footer. Were I in this picture, the top of my head would barely reach the larger animal's knee. Even the "babies" shown here would outweigh me by a big factor. The teeth of an adult T. rex are the size of bananas. Big bananas. Perhaps Plantains.

I have great admiration for men like Brown who can go into the field and bring back cool stuff. My style of collecting is day trips…no more weeks in a tent for me!

Friday, September 26, 2025

Admirable serpents

 kw: book reviews, nonfiction, science, herpetology, snakes, serpents

Let's start with a couple of anecdotes. We lived in Ohio when I was a teen. One summer my brothers and I found several small, brown snakes in a field. At first we thought they were baby copperheads. We watched them for a while. Soon we saw that when they were relaxed, their heads were oval, not triangular like the head of a copperhead. We checked in the encyclopedia (this was decades before the Internet was even a pipe dream), and learned that they were DeKay's brown snakes. Their resemblance to a copperhead was protective coloration. When bothered, one would pull its head back to make it look more triangular and strike the way a copperhead does. But their tiny teeth couldn't even draw blood. A day or two later our great uncle Verne, who lived in Missouri, came to visit. One of my brothers and I ran to the field and brought back several of the snakes to show him. He was terrified! Particularly when he saw one of them rear back and strike me, biting my finger. I showed him that it had no fangs and was harmless. He was still uneasy, so we ran back and let them go. 

Jump forward about fifteen years. One of my summer field camps during my Senior year as a geology student was in eastern Nevada, in the White Pine Mountains. I saw rattlesnakes every day. Although they can't "hear", not having ears, they can sort of hear by putting their jaw on the ground to pick up vibrations. They know when people are near from the way our footsteps reverberate in the soil. Whenever I saw one it was usually slithering away, having detected my approach already. I value rattlesnakes because they eat most varmints, such as rats, so I left them alone. Another couple of years later I was with a group of rockhounds and their families in the Mojave Desert. The first morning I took an early walk and encountered a sidewinder (a kind of rattlesnake), coiled near the camp, apparently asleep. I went back to confer with the others. Because small children were with us, we decided it had to be removed or killed. I went back and killed it. I hated to do so, but there was too much danger leaving it there.

One more story, a fun one. Before I was married I lived in East Los Angeles with a few other single brothers from the church. We had a house in a little forested valley, a kind of enclave surrounded by a neighborhood. The youngsters in the neighborhood, ages 12-15, all belonged to a gang; everyone 16 and older was already in jail or prison. The gang leader, Tony, lived next door to our house, just outside the valley. One day I happened upon a king snake coiled near our gate, between our yard and Tony's family. I could see Tony in his yard so I called him over. He was frightened. I picked up the snake; it was about five feet long. After it calmed down (it liked my warmth) I asked Tony if he wanted to hold it. He reached out and it bit him! I showed him that the little tooth marks on his hand weren't fang marks, and taught him how to ease the snake into his arms. Then he took it home to show his mother. When he came back and returned the snake to me, it reared back and bit him again! I said, "Tony, that snake's telling you that you need to get right with God. Otherwise the real 'snake', the Devil, will devour you." I don't know if Tony decided to believe in God, but his attitude toward me was much more respectful after that.

When I saw Slither: How Nature's Most Maligned Creatures Illuminate Our World, by Stephen S. Hall, I really hoped to learn a few things. The book didn't disappoint me. The eight chapters limn various aspects of snakes and their intersection with society and science. Each chapter includes a coda titled "Snake Road" with a focus on a relevant aspect of snakehood.

Studying snakes is trickier than most genres of natural history. Most snakes are very good at staying out of our way. The only exception I know of is the cottonmouth moccasin, which seems ready to confront any human who has the trepidation to enter its territory. Of course, I am familiar only with North American snakes. Other continents and countries have their own species, and their own histories of human-serpent contact. For example, half of all snakebite fatalities happen in India, some 60,000 per year. I suppose that cobras are more territorial than rattlesnakes.

In the last chapter, about the attempt to deal with invasive Burmese pythons (and the even larger Burmese-Indian python hybrids), we find that the snakes are so well camouflaged that when expert snake finders (perhaps only in their own eyes…) were tested in an enclosure smaller than a suburban yard, containing a dozen "planted" pythons, most found exactly none, and only a two saw even one of the snakes. The conclusion of Chapter Eight is that the pythons of southern Florida, descended from escaped (or released) pets, are already too numerous and too widespread to be eradicated. The chapter subtitle, "Adaptation," says it all. Snakes have been found to be genetically pre-loaded with an enormous "toolkit" that allows them to adapt to a new environment a whole lot faster than anyone imagined before.

A case in point. The females of one species of snake (I don't recall, and I didn't note it down) usually reproduce at least once yearly, after maturing in about three years. However, during a prolonged drought, they can take ten years to mature and may reproduce only once per decade. That's rather extreme adaptation, and it takes place during one generation, so natural selection isn't operating here. Rather, natural selection already operated in prior generations to produce a species that can manage such a wide range of environmental variation. Only humans have a wider range, and we need cultural and technical means to do so. A snake is born naked, stays that way, and just handles whatever nature throws at it.

We think of snakes as the prime example of being cold-blooded. It turns out that pythons are usually able to keep their body temperature in a narrow range near 85°F (29°C). That means on a cool morning snake hunters could use a thermal camera to look for them. If a snake is in the water, that won't help, but on land any thermal anomaly that's cooler than a mammal but warmer than the dirt would be worth a look.

Backing up a couple of chapters: Chapter 6, subtitled "Reproduction," is titled "The Evolution of Pleasure." It takes a pretty solid bit of evidence to determine if a snake can experience pleasure. A group of researchers gathered the most solid evidence possible: they discovered that female snakes have a clitoris…or, rather, that they have two, just as the males have paired penises (eat your heart out, Casanova). I'll just leave that right there for you to think about.

Earlier yet, we learn a lot about venom, including the likelihood that even "nonvenomous" snakes actually have a little venom in their saliva. In a "harmless" snake like a garter snake (or DeKay's brown snake) there is apparently a little cocktail of toxins that might be relevant to subduing their prey, but don't cause a reaction in us. I suspect the risk of infection from a garter snake's bite is greater than any risk from whatever toxins might be in its saliva. But venoms are proving useful. The components that silence nerves, or cause muscle tissue to die, and even the ones that intensify pain, are being intensively studied to learn what signaling pathways and cellular receptors are affected. These can then become targets for drug discovery to deal with medical conditions. Components of various snake venoms are also being repurposed as medical substances. Per the proverb of Paracelsus, "The dose makes the poison," a tiny bit of certain toxins can be very beneficial. It reminds me of the use of Botulin toxin (Botox), not only for cosmetic use, but as a safer alternative to curare to induce localized, but longer-term, paralysis without causing permanent nerve damage.

The author hopes more people will learn to appreciate snakes. I guess I'd propound a proverb here: Snakes have a lot to teach us, we simply need to learn how to listen.

(Image generated with SeeDream 4.0 in OpenArt)

Thursday, September 18, 2025

Noise is about more than loudness

 kw: book reviews, nonfiction, science, sound, noise, soundscapes

For about ten years I have worked part time at the Delaware Museum of Natural History (renamed in 2022 the Delaware Museum of Nature and Science). My "office" is on the top floor, above an exhibit hall. During the times the museum is open to the public, I constantly hear the sounds of children talking and shouting in the hall below. I happen to like it. Happy sounds are good sounds. On occasion I venture downstairs to wander among the exhibits. There, the sound is much louder, particularly where there is an exciting exhibit in that exhibit hall. The sound is equally happy, but at that volume, it soon gets tiring and I go back upstairs.

I haven't measured the sound level at the museum—I only recently downloaded an SPL (Sound Pressure Level)  app—but I estimate that the loudness at my desk is about 65-70 dba, about as loud as an older washing machine. Down in the hall, it must be 80 dba or more, with peaks in the 90's…there is nothing quite like a surprised child's shriek!

Near a busy highway, the loudness is also in the 70 dba range, but it is definitely not a happy sound, unless you happen to be a tire salesman and the sounds of tires wearing out leads you to anticipate future tire sales. Few of us treasure the noisy clangor of a busy city street. We go where we must, but when we have a choice, we prefer sounds that are more pleasant, and, importantly, less loud.

The coupled measures of loudness and pleasantness are teased apart for us in Clamor: How Noise Took Over the World and How We Can Take it Back by Chris Berdik.

A definition for those needing it: "dba" means "A-weighted decibels". It is a measure of the intensity of sound, with zero set at the threshold of human hearing. "A-weighting" adjusts the sensitivity at different frequencies to match our ears' sensitivity. The scale is logarithmic, so that an increase of 10 dba means a tenfold increase in sound intensity. Most people consider a 10 dba increase to be "twice as loud," because our senses also follow a logarithmic response.

The app I used to measure sounds after I began reading the book is "SPL Meter" by Keuwlsoft. When installed, it arrives uncalibrated, and I could tell it was reading quite high. I don't have a sonic reference, so to reach an approximate calibration I used several well-reported sounds to set the calibration. Now its readings are about 15 dba lower than before and they accord well with reported measurements. I went around during the past week gathering measurements. I'll discuss a few of these below. The reading shown in this image measures the loudness of a particularly low-flying jet aircraft as measured in my front yard.

The book chronicles the very gradual development of public policy regarding noise. The sonic environment has been ignored almost universally, perhaps with the exception of some of those who plan parks and open spaces such as Central Park in New York City. Central Park is big enough to keep the city's traffic sounds at bay, and many sheltered areas are quiet and restful. Even more so, the gentle forest sounds are soothing, quite in contrast to the typically jangly background noise of a city.

The author's aim is not to add another tome to those extolling quietness and denigrating loudness; rather, his interest is the quality of the sounds that envelop us. Many of us greatly enjoy attending concerts, where the louder sounds threaten to damage our ears; this is more so at a rock concert than at an orchestral concert. But, I have attended an outdoor concert of 1812 Overture by Tchaikovsky that used real cannons. There, it was worthwhile to put one's fingers in one's ears whenever the conductor pointed at the cannons! As fun as that was, I don't listen to loud orchestral music all day long. One of my relatives was a rock drummer for a while and has significant hearing loss. I am a folk singer; we don't go for volume, but for lyrics that touch the soul.

Let's consider: what could make the sounds of a city less stressful? Nearly half of Clamor is about that, about the researchers and companies that design soundscapes. The idea of a soundscape is not to just subtract unpleasant sounds, but also to mix in more pleasant sounds.

Here is my own soundscape practice: As I hinted above, jets fly over our house from time to time. Our neighborhood is in line with one of the runways at Philadelphia Airport, and when the wind is right, the landing pattern has jets sweeping in from all directions to a spot about a mile west of our house, then making a descending beeline for the runway. Most of them are still about a mile high when they cross over, and I've recently measured their sound intensity to be 75 dba. Most of the jets are either a Boeing 737 or an Airbus A320. When a larger plane passes over, not only is it intrinsically louder, but it is usually lower, producing the louder sound recorded above. 80 dba is as loud as my lawn mower, heard from 2 meters away (where my ears are during use). Inside the house, where the background sound level is 24 dba (just a bit louder than a whisper), a jet flying over registers 48 dba, except the big ones exceed 52 dba. Sometimes I take an early afternoon nap. Since 40 dba is generally considered loud enough to disturb sleep, I do this: I turn on the clock radio and reduce the volume until I can't understand the words, but the gentle susurrus of human voices is a kind of white noise that helps me "not hear" the jets when they fly over. My nap is better as a result. The Internet is full of suggestions for private soundscapes: little fountains, audio files of forest sound, playlists of gentle string music, etc., etc.

What is a good soundscape for an office? What do you want to be hearing as you work? What, if anything, should be the background sound for a business meeting, particularly for hard negotiations? All these are being studied. Some progress is being made. Several chapters deal with various aspects of such work.

It's very important to understand that people are hugely various. In the realm of felt experience, "diversity" is much more than ethnicity. Not everyone enjoys the sounds of happy children; some people find it excessively annoying. Most people I know enjoy rock music. There are a very few rock musicians and composers whose work I appreciate; I hate most of it. I like classical music, almost exclusively pre-1900; "12-tone" and "atonal" compositions are just meaningless noise to me. I like country and folk music, but mostly for the lyrics. I like the sounds of a babbling brook in a quiet forest, as seen in this picture, taken in a small woods near our house. Many people would find it either annoying or boring. The sound intensity in this woods is as low as 50 dba, which is "quiet" as defined by urban planners.

I did the following measurements this past week:

  • 48 dba outside my front door in the daytime. Most of the sound I could hear was road noise from a highway 1/3 mile (~550 m) away.
  • 65 dba from the same spot, when my neighbor across the street accidentally set off his car alarm. Fortuitous timing! The sound is designed to be annoying, to get attention. Most of us have learned to tune it out, making car alarms largely useless.
  • 65 dba (ranging from 62-74) seated with friends in a restaurant that doesn't play background music. The higher reading was during conversation at our table.
  • 50 dba in the forest as noted above, but...
  • 60 dba when crows were calling nearby.
  • 82 dba, my lawnmower at 1 meter.
  • 79 dba, my lawnmower at 2 meters. Note: a difference of -3 dba indicates the intensity was one-half. Power is proportional to the square of intensity, so this follows the inverse square law: -3 dba is one-fourth of the sound power.
  • 64 dba is conversation in an otherwise quiet room. Note that we spoke louder in the restaurant setting.

Clamor comes along at the cusp of a revolution in architecture, city planning, and numerous disciplines that have historically ignored sound. The book is not prescriptive; it is reporting on progress as it happens. I hope in just a few years to find that the sonic environment is more and more taken into account everywhere. I am fortunate to live in a quiet suburb. May those living with more noise soon find that the sounds around them are changing to reduce stress rather than enhance it.