Monday, June 26, 2017

When the math you used could mean life or death

kw: book reviews, nonfiction, mathematics, geometry, analysis, renaissance

Who would have thought that for a period of decades a student's adherence to certain mathematical methods could get him in trouble with the Inquisition, imprisoned, or even burnt at the stake. Galileo was placed under house arrest for the last two decades of his life, not only for advocating the motion of the Earth, but also for the kind of mathematical analyses he published!

Infinitesimal: How a Dangerous Mathematical Theory Shaped the Modern World, by Amir Alexander, chronicles the development of a "new" kind of mathematics, one that had actually existed alongside Euclidean geometry for centuries, but had been little used and was denigrated by Aristotle and others. It flowered along with the Italian Renaissance, but ran afoul of the reactionary politics of the Jesuits.

To most mathematicians of the early Renaissance, mathematics was geometry, and all proofs and analyses that proceeded by any method other than straightedge-and-compass derivation from first principles were suspect. It is rather amazing to read how the Society of Jesus, originally rather blind to mathematics because of the proclivities of its founder, Ignatius of Loyola, took up Euclidean geometry as a point of pride within a generation after his death.

In their to-the-death struggle to throw back the influence of the Protestant Reformation, the Jesuits, brought into being as the Reformation was blossoming throughout Europe, realized that geometrical proofs provided a perfect model for their rigid theology and social structure. The Reformers declared that all persons had a right to know and understand Scripture, and offshoots such as some Anabaptists, and free-land proponents such as the Diggers, began to question the "divine right of the King" and the "natural order" of aristocracy. Dogma was being replaced by opinion. Long-held traditions were in danger of being overthrown. Chaos was imminent. The execution of the English king Charles I emphasized the danger.

If one accepts the validity of the methods of Euclid, there is no room for opinion. A geometrical constructive proof, proceeding by pure deduction, leads step by step to a conclusion that cannot be denied. But it had become evident to the disciples of Pythagoras, nearly a full twenty centuries earlier, that some propositions one could state, could not be proved. They had begun by proclaiming that all problems were subject to "rational" proof; by "rational" they meant using only ratios of whole numbers. An early demonstration that the hypotenuse of a square could not be exactly expressed as a ratio, that it was "incommensurable", led to the breakdown of the Pythagorean system and eventually to the disbanding of the Pythagoreans.

By Aristotle's time, about 200 years later, inductive methods based on "indivisible" quantities had shown some promise, and had been used to demonstrate certain propositions that geometric methods could not solve. But Aristotle, at first intrigued, later decried such methods. Euclid he could understand; the new methods seemed to allow a certain leeway for error. In his way he was as rigid as any Jesuit of the Sixteenth Century.

I have often been astounded that the Medieval Roman Catholic Church based so much of its philosophy on Aristotle, whose only brush with Theism is some vague statements about an "unmoved mover." I was further amazed to read of the process that led to this, via Thomas Aquinas. The Jesuits believed that Aristotle had it right. Mathematical induction by "indivisibles" (also called "infinitesimals" after about 1730) was unreliable. The Church needed … NEEDED! … a rigidly reliable theology and rule of society that disallowed dissent as thoroughly as a Euclidean proof disallows "alternate opinion". Galileo was only the most prominent of a large number of Italian mathematicians to learn of inductive methods, and use them to great effect, so much so that these methods swept through Europe. But over about a century's time the Jesuits drove "indivisibles" out of Italy. Indivisibles and inductive methods flourished elsewhere, in all the countries of Europe.

Reasoning similar to that of the Jesuits led Thomas Hobbes to found his political philosophy on Euclidean geometry. He strongly felt that the chaos following the Reformation simply cried out for a more totalitarian form of government. His exceedingly famous book Leviathan proposes the most profoundly totalitarian political system ever devised. When he learned that three very significant propositions were incommensurable via Euclidean methods, he realized that this left a great loophole in his philosophy.

Three problems: Squaring the Circle (making a square with the same area as a given circle), Trisecting an Angle, and Doubling a Cube (constructing a length that can be used to construct a cube with twice the volume of a given cube). None of these can be done using Euclidean geometric methods. This has been proven, using mathematical methods developed centuries after the time of Hobbes. He spent the rest of his life trying to square the circle, and eventually lost his reputation as a mathematician. He ran afoul of Gödel's Incompleteness Theorem: that every mathematical system can be used to formulate problems that cannot be solved withing the confines of that system. This includes geometry. But Kurt Gödel was two centuries in Hobbes's future.

In the opening chapters of the book, it seemed to me that "indivisibles" and "infinitesimals" were described as being in opposition. It took careful reading to understand that they were synonyms separated by a century or two of usage. They form the foundation of The Calculus, as developed by both Newton and Liebnitz. The modern world would not exist without the analytical methods of calculus. From a modest number of "demonstrations" using induction—based on lines being composed of an infinite number of "indivisible" points, planes being composed of indivisible lines, and volumes being composed of indivisible planes—calculus and modern analysis in general have become supercharged, and now include both inductive and deductive methods.

I spent much of my adult life as a working mathematician, and I find it fascinating that such a life-and-death struggle had to be won, and won decisively, for the modern, technological world to appear. I have just touched on a few of the trends and a handful of the players in the saga of Infinitesimals. I have to mention John Wallis, whose 25-year battle with Hobbes "saved" inductive mathematics in England. How much longer would the modern era have been delayed otherwise? He originated the symbol for infinity: . Infinitesimals is quite an amazing story, very well told.

Sunday, June 18, 2017

Wu Li: Circular reasoning to the max

kw: book reviews, nonfiction, physics, cosmology, buddhism, copenhagen interpretation, quantum mechanics

From time to time I have heard about The Dancing Wu Li Masters: An Overview of the New Physics, by Gary Zukav, since it was published in 1979. I had never read it until now. As a student of all the sciences, particularly the "hard" sciences (those amenable to experimental verification), since before 1960, I have at least a reading familiarity with physics, which is a hard science, and cosmology, which is not. Now having read the book, I find it contains no surprises, at least, none of a scientific nature. Of course, a lot has happened in physics and cosmology in the past nearly forty years.

The author, an admitted outsider to the field of physics, conceived of the book while on a retreat at Esalen along with a real mixed bag of folks including numerous scientists and science hangers-on (some would consider me more of a hanger-on, though I am a working scientist, even in "retirement" from a career in the sciences). Al Huang, who was teaching T'ai Chi at Esalen when Zukav was there, introduced him to the concepts of Wu Li. That is concepts, plural.

I have a great many Chinese friends. The Chinese languages, primarily Mandarin, the principal written Chinese language, abounds in homophones, words that sound the same, at least to a Westerner. Most basic Chinese words consist of one syllable, and very few require more than two syllables. Spoken Chinese sounds to us like a long string of only a few syllables repeated various ways, with a "sing-song" quality that means nothing. What Westerners miss is that the "sing-song" variations in tone are meaningful and are part of the proper pronunciation of Chinese words. Thus, the syllable "MA", depending on the tone, and its context in a sentence, has at least these meanings:

  • Mother.
  • When doubled, an affectionate term for Mother, just as in English, at least when pronounced with two flat tones.
  • Horse, using a different tone.
  • The verb "ride", when the context demands a verb rather than a noun, and using still another tone.
  • The pronounced question mark that ends (nearly) all Chinese questions, spoken with a rising tone.

The familiar greeting "Ni Hao Ma" is a lot like the New Jersey, "How are ya?" The Chinese sentence, "Ma-ma ma ma ma", with the proper string of tones, means, "Is mother riding the horse?" (Chinese has no articles, so "the" is implied).

Depending on tone and context, "WU", pronounced "woo", has about 80 meanings, and "LI", pronounced "lee", has a great many, primarily focused on pattern. Different written Chinese characters (ideographs) are used for the various meanings of wu and li. In combination, the word wu li is the primary Chinese term for "physics". But when other combinations of ideographs with the same pronunciation (except for tones) are used, there are other meanings. In the context of this book, Al Huang gathered five. The literal meaning of the ideographs used for wu li meaning "physics" is "patterns of organic energy". The other four are "my way", "nonsense", "I clutch my ideas", and "enlightenment".

The book is structured around these five concepts, with each section containing two or three chapters. As I might have expected from a book inspired at Esalen, each chapter is numbered 1.

The "new physics" on which the book is centered is quantum mechanics and its relationship to Einstein's theories of relativity (special and general). The core message is the ambiguity of quantum phenomena—when any single "particle" is studied—coupled with the exactitude of the predictions the mathematical theories of quantum mechanics make regarding the statistics of interactions when many particles are subjected to the same set of conditions. The "scripture" of quantum mechanics is the Copenhagen Interpretation, that of Niels Bohr and his followers (I almost wrote "disciples").

Thus, for example, when light is shined through a pinhole, which spreads the beam by diffraction, and this beam is passed through a pair of narrow slits, an interference pattern emerges. This works best when monochromatic light is used, such as from a laser, but "near-mono" filtered light works well enough for visual purposes. The intensity in each part of the interference pattern can be exactly calculated by the Schrödinger wave equation, although the calculations are formidable; various simplifications of the wave equation yield very precise results with less arithmetical grinding.

I mentioned diffraction. This matter is first mentioned on pages 64-65 of the book. In the upper half of an illustration, a series of waves in a harbor are shown exiting a rather broad opening, and those that get through are shown going straight onward, with a sharp edge to their pattern. In the lower half, the opening of the harbor is smaller, and the waves exiting are shown as semicircular wave fronts spreading beyond the opening. There are two major errors here. Firstly, the upper pattern should show a little spreading at the edges of the "beam" of waves exiting the harbor (you can verify this using a wave tank, as I was shown decades ago in a Freshman physics class). In other words, diffraction occurs when waves pass through any opening of any width, not just very narrow ones. Secondly, for the lower wave pattern, the wavelength of the exiting waves is drawn as much shorter than the waves in the harbor.

In actuality, diffraction produces a nonzero probability of the waves at every angle. They seem to "go straight" through a larger opening only because the off-axis waves lose energy with angle very rapidly in such a case. When a wave front passes through an opening of a size similar to the wavelength, or smaller, there are significant amounts that are found at nearly every angle, making a much more divergent beam. Zukav seems to have been ignorant of this.

Interestingly, if a double-slit setup using extra-sensitive photographic film is set up, you can get a surprising result. The best photo film can record the capture of each photon, as long as the light is blue enough, meaning the photons are energetic enough. One silver halide grain is exposed by the capture of a single photon. If the light is dimmed enough that only a few photons per second pass through the apparatus, and you let it run for less than a minute before extracting the film and developing it, the developed film will have one or two hundred tiny exposed grains that are seemingly scattered at random over the film. If instead, you leave the film in place for an entire day, there will of course be many more exposed grains, tens of thousands of them. They will show a very clear interference pattern, identical in form to the one you could see when the light was shining brightly and tens of trillions of photons per second were passing through the apparatus.

Interference is a wave phenomenon. Photons are particles; each carries a specific amount of energy and has a specific momentum (these are all the same for monochromatic light). It took me and all my fellow students a long time to become comfortable with the fact that light has both wave and particle characteristics. Eventually we thought of a photon as a "wavicle", a small wave bundle, that could somehow "sense" that both slits were open and "interfere with itself", when passing through a two-slit apparatus. It seems that light behaves as a wave when wave "behavior" is demanded of it (the two slits), and as a particle when particle "behavior" is required (exposing a silver grain in the film).

Where does Gary Zukav take this, and several other experimental results of quantum mechanics, special relativity, and general relativity? Straight to the door of a Buddhist sanctuary. The language he uses is usually as ambiguous as the language physicists typically use to describe concepts like the "collapse" of a wave function when an "observation" is made. He compares some conclusions and statements of physicists to similar statements of Buddhist doctrine, though I could seldom recognize the resemblance. The core of the Copenhagen Interpretation, at least as it is explained in this book, is that the Observer is central. But, to date, nobody has adequately defined "Observer". That doesn't stop Zukav from equating the one-is-all-all-is-one that he believes the new physics is trending toward to Buddhist teachings of the pre-Christian era. I have a question or two about observers, or Observers.

Must an Observer have a self-aware mind? Can the photographic film described above be an observer, or has no observation been made until the film has been developed and a human (or other self-aware entity) has looked at it to see the pattern? If I understand the Gary Zukav presentation of the Copenhagen Interpretation, there is no "collapse" of the wave function into an actual "event" without an observer. It is as though, outside your peripheral vision, nothing exists until you pay attention to it. Taken to an extreme, it means there was no Universe until humans evolved to be the Observers to bring it into existence. This is the reason for the title of this post. If this is actually what Niels Bohr believed, I have to say to him and his disciples, as Governer Festus long ago said to the Apostle Paul, "Much learning has driven you insane!" Paul was not insane, but I think Zukav might be. More on this anon…

At the time The Dancing Wu Li Masters was being written, some "newer" new physics concepts were arising, such as the Quark/Gluon resolution of the Particle Zoo, and the theory of the Multiverse. To take up the former: It appears that the quark is truly fundamental. All the hadrons seem to be made up of various combinations of quarks and anti-quarks. However, it takes such enormous energies to generate interactions that give evidence of the existence of quarks—and they apparently cannot be brought into independent existence—that we may need to await a particle accelerate wrapped around the equator of the Earth to achieve energies sufficient to determine whether quarks do or do not have any substructure. Apparently, electrons have no substructure, so maybe they and quarks are as fundamental as it gets. But our experiments have reached "only" into the range of 10 to 100 TeV. What might be achieved with an energy a thousand times as great, or a million? Fears have been expressed already that the current experiments at CERN could trigger destruction of the Universe. Maybe the Multiverse is real, and we inhabit a surviving Universe that didn't get destroyed.

The notion of the Multiverse is simple. Rather than the wave function for a particle "collapsing" into some actual event, an entirely random outcome within the statistical framework described by the wave function, perhaps every possible outcome actually occurs, and a new Universe is spawned to contain each of those outcomes. This is simple enough if the "outcome" is that a particular photon passes through either the left slit or the right slit of a two-slit apparatus. Two universes result. I one of them, the photon passes to the left, and in the other, it passes to the right. But there is detail in the interference pattern, and when I have done the experiment with a laser pointer and a home-made pair of slits cut in aluminum foil, I could see more than twenty interference fringes. Now what? Did each photon create twenty or more universes to accompany each outcome? When the light is bright enough to see, trillions of photons per second are "in use"; the beam of my laser pointer emits 200 trillion photons or deep red light per second. Did I inadvertently create a few quadrillion new universes, just by shining my laser pointer through a pair of slits? Were new universes being created at the same rate even when I wasn't looking?

So what are the chances that the search for the Higgs boson at CERN caused the creation of truly enormous numbers of universes, nearly all of which were immediately destroyed, and we inhabit one of those that survived. I think you can see where such thinking can lead.

And some folks say that I am crazy to believe in God, a God who knows a level of physics (if it is called that) that can resolve this stuff, without the insanity of Multiverse speculations. I think it is fair to say that "modern physics" has reached a point of adding more and more epicycles to a group of theories that seem to produce very precise results, but that they are really analogous to pre-Copernican cosmology. Actually, Copernicus used epicycles also, because he thought orbits were based on circles. It took Kepler and others to work that part out.

Another item or two that have arisen in physics since 1979:

  • On page 119 we read, "No one, not one person has ever seen an atom." If you are talking about direct visual sight without the use of a microscope, you could say the same thing about bacteria or viruses. But we have microscopes of several kinds that can show us what they look like in rather amazing detail. Since about 1981, highly refined transmission electron microscopes have been able to show atoms directly, and since the invention in 1982 of the scanning tunneling microscope and the atomic force microscope, we now have three methods for seeing where the atoms lie in a surface. Whatever point the author wished to make based on the above statement is now moot.
  • Beginning on page 292 we find an illustration using polarized light. Simply put, when light is passed through a polarizer (such as the special plastic in some sunglasses), the light that emerges is now all vibrating in the same plane (for convenience, we use the electric vector as the "direction" of polarization, though the magnetic vector could be used equally well, and is at 90° to the electric vector. Zukav does not mention this). When you place a second polarizer with its polarizing axis at 90° to the first, it blocks all the light. If you rotate it to various angles, some of the light gets through, in accordance with an elliptical formula. Now, if you set the two polarizers so their polarization axes are at precisely 90° so that no light is getting through, then put a third polarizer between them, with its axis oriented at 45° to the other two, quite a lot of light gets through! This goes on for several pages and is presented as quite a mystery. Strangely, elsewhere in the book we find the tools to solve this mystery (I didn't look up page numbers):
    • In a discussion of Feynman Diagrams and the S-Matrix (Scattering Matrix) we read that physicists consider every interaction to entail the destruction of all the impinging particles and the creation of new ones that exit the interaction locus at the appropriate angles with appropriate velocities. Thus, when a photon reflects off a mirror or any shiny surface, it is actually absorbed and a new photon is released at the appropriate angle. So they say. Refraction works similarly. Thus, the polarizer absorbs the incoming photons and releases a somewhat smaller number of photons, all with the appropriate polarization.
    • As I recall, a polarizer made of stretched plastic film passes 38% of the original light. A Nicol prism can actually split light into two beams with nearly no loss, so that 50% exits with horizontal polarization at one angle, and 50% with vertical polarization at a different angle. This would make no sense according to the "picket fence" analogy, because very, very little of the original light could get through any polarizer: only that which is already polarized the "right" way. Thus, a Nicol prism, in particular, "tests" each photon, and either twists its polarization to match the nearest direction (and shifting its exit angle according to the one or the other), or annihilates the photon and emits one of appropriate polarization and exit angle.
    • Polarizing plastic is less efficient, passing only light of one polarization, but obviously changing whatever the polarization was of most photons to match its orientation. Thus, what is happening with the 45° polarizer is this: it absorbs some photons entirely, and twists the polarization of the rest of them by 45°. Then when they reach the last polarizer, they are now subject to a further absorption or twisting, so that the "twisted ones" get through, with perhaps 5% of the original beam intensity. That is a lot more than the fraction of a percent that "sneaks through" the original set of crossed polarizers because plastic film polarizers are not perfect.
    • So polarizing devices do not just passively allow certain photons to pass and block all others, but they change the polarization of the photons that they allow to pass.
  • I cannot pass by the chance to mention circular polarization. A thin piece of calcite or quartz (or, indeed, any colorless crystalline material that does not have cubic molecular symmetry) rotates the polarization of the incoming light. What is more, if it is just the right thickness, it will produce circularly polarized light. This is sometimes thought of as two streams of photons that are related to one another. Think of a vertically polarized photon coupled with a horizontally polarized photon, and their "waves" are out of phase by a quarter of a wavelength. Then, in effect, their polarization will rotate as the go.

As interpreted by Gary Zukav, physics was becoming one with Buddhism. I wonder what he would make of today's situation, with the great popularity among physicists of cosmological string theories (at the moment, they can't decide which of the potential 10500 possible string theories to favor!), the supposed detection of increasing cosmological expansion that may lead to a "big rip" in which all things will be literally shredded to their composite quarks, and the theory of cosmological inflation (developed in the early 1980's) that supposes that the initial expansion of the big bang took off at several trillion trillion trillion times the speed of light for just a tiny fraction of a second, during which the Universe grew to a size somewhere between that of a grapefruit and a galaxy (nobody can pin that down too precisely).

In my view, coupling physics theorizing with Buddhism is tantamount to solipsism. Let us accept as a first premise that what exists, does indeed exist, and go from there. Then the extreme versions of "New Physics" simply vanish, like an unobserved photon.

Saturday, June 10, 2017

The public versus science

kw: book reviews, nonfiction, science, sociology, anti-science sentiment

Someone once described scientific law as "What always happens." They were referring to things like "the law of gravity", which is a colloquial way of saying that what goes up must come down.

There is a commonplace view that flying things such as birds "defeat" the law of gravity because they have a flying life, a "different law". Only when they die do they succumb to gravity. In reality, birds take advantage of gravity to fly. The way they fly requires the gravitational force to keep "the wind under their wings". A bird in a zero gee can't orient itself (see this video for an example). Given time, a bird might learn to compensate to some extent, but fast, directed flight requires gravity as one of the forces the bird is adapted to naturally balance.

This is one example of someone getting something partly right because of partial scientific knowledge. While we all take great advantage of technology—all the gadgets and appliances around us—most of us know little about what those things do. Decades ago Arthur Clark wrote, "Any sufficiently advanced technology is indistinguishable from magic." For most folks, their phone or auto engine may as well work by magic.

A million years ago, advanced technology was the hand axe. Anyone could make one, though few could make them well. 150 years ago, advanced technology was an automobile. Few could make one, but many could repair them. I grew up learning to do my own oil changes and even did major engine work. My Dad and I rebuilt a VW engine once. I wonder how many backyard mechanics could rebuild the engine of a 2017 Honda Civic or Chevy Impala! The fuel injection system of a 2017 Impala has more moving parts than the entire assembly under the hood of that 1964 VW I had.

There are two fundamental barriers that impede the majority of people from learning science. First, science has proceeded in a stepwise manner, primarily for the past 500 years (with a few 2,500-year-old roots), and to truly comprehend (let alone understand), say, chemistry, geology, physics, botany, zoology, or microbiology (and let's not mention medicine!!) requires years of study to build the core structures in a person's mind that were discovered by hundreds of scholars and experimenters over the past half millennium.

The simplest example is mathematics. We are all able to use basic arithmetic. We learn that 2+2=4 by counting on our fingers, by lining up stones, and many other ways. Probably our first mental step is realizing that negative numbers and zero are useful. Then we learn about fractions, maybe decimals…but it is questionable whether most people ever grasp irrational numbers, even though the vast majority of actual quantities are irrational. And we haven't even got to algebra yet, which forms the foundation for all the disciplines of calculation needed for all engineering and science. Without a solid grasp of algebra, we cannot put useful amounts of geometry, trigonometry, and calculus into our mental toolbox. I thought I was pretty good at mathematics when I gained a solid (so I thought) facility with calculus. Then in graduate school I learned that calculus just opens the door to more dramatic realms of mathematics, which I would need to master to succeed as a geophysicist. I barely made it. I was still not anywhere more than halfway up the mathematical ladder, and did not proceed farther. Most of us never need to proceed anywhere near that far, but if we can't even handle basic algebra (most of us can't), most physical science remains a mystery to us.

The second barrier is that science requires thinking. Sustained thinking. Not the kind of quick figuration we all use to perform most paying jobs. We all start out as sprinters in that realm. It is like we are all born to be pretty good at the 50- or 100-meter dash. But to grasp science requires marathon-level mental performance. Fortunately, understanding the basic concepts of most fields of science is more like running a quarter or half mile; a bit of a stretch for a sprinter, but achievable. Of course, it is hard work. It makes you tired. Most folks aren't willing to put in the work. And so, lacking a tremendous level of effort by both teachers and parents, the vast majority of people grow up with only the haziest notion of the way things really work.

Take eyesight. What happens to make your eyes see? I understand from material presented in Scienceblind: Why Our Intuitive Theories About the World are So Often Wrong, by Andrew Shtulman, that most of us think that our eyes work by sending some kind of ray outward, and receiving it back. Kind of like the comic book illustrations of Superman's X-ray vision, where the X-rays went out from his eyes so he could see through things. But if such a belief were true, you would be able to see in the dark. It would not matter whether or not the sun was up or a light was turned on. Just by turning out the light and thinking hard, we can usually figure out that "light", whatever that is, scatters off of things and gets to our eyes, which receive it and are then able to "see".

Andrew Shtulman is concerned that the level of science ignorance, particularly in America, is so great that very few of us can make proper decisions about most technical issues. For example: Do vaccinations cause autism? Certain influential people loudly proclaim that they do, to the extent that many people, not wishing to leave anything to chance, ignore the protestations of every single scientist who has actually studied that matter. If you never get it anywhere else, get this true knowledge right here: Autism is not caused by any of the chemicals or deactivated organisms in vaccines. The proportion of autistic children among those vaccinated is exactly the same as the proportion among those not vaccinated. Period.

Dr. Shtulman presents twelve kinds of knowledge in which we form "natural concepts" or what he calls "intuitive theories". They are all based on everyday experience. For example, when you throw a ball, what path does it follow? Does it rise gradually to a maximum height and then descend just as gradually? Or does it rise up, hang a while, and then fall straight down? Because of perspective, as the thrower, we see it appear to rise, hang, and drop. But have you ever carefully watched a ball thrown by someone else who is some distance away? For example, at a ball game, if you are in the seats either behind home plate or out beyond second base, watch a "clothesline peg" from the third baseman to the first baseman. It is called a "clothesline peg" because a ball thrown hard seems intuitively to go "straight" from hand to glove over a distance of about 125 feet. But if you watch carefully, you'll see that the ball rises at least 16 feet, in a smooth curve like a stretched circular arc (a parabola), and is highest when it passes over the pitcher's mound. It is actually thrown upward at an angle greater than 25°, and is descending at that same angle when it reaches the first baseman's glove.

One of the hardest concepts for most people to grasp is "deep time." I was lucky to have preparation from a young age, when my parents told me that the Earth and the Universe are very old. We were Bible-believing Christians, but one of the first things I was taught, probably from about age seven, is that there is a "gap" between Genesis 1:1 and 1:2, between "God created" and "The earth became". Thus, when science teachers in middle school began talking about millions of years having passed, I was not ready to receive it.

We naturally think of most things happening on time scales that are familiar to us. When I first knew my grandfathers, born in 1885 and 1887, they were nearly 70 years old, and in the early 1950's, that was old! Growing up on Bible stories, I was familiar with stories of Jesus and his apostles, who lived nearly 2,000 years before, and Abraham, about 2,000 years before that. I remember as a sophomore in High School learning that when Caesar and Cleopatra went sightseeing along the Nile, the Pyramids were already about 2,500 years old and were considered "ancient history". Particularly in America, few of us know of any building older than 300 years, though some kids in Illinois grow up in sight of the Cahokia Mounds, which are between 600 and 1,200 years old. Even residents of Damascus and Jerusalem seldom see a building older than 3,000 years. So to our natural way of thinking 10,000 years is "really long".

Now imagine one hundred times ten thousand: 100x10,000. That is one million. A human generation is about 25 years. A million years is about 40,000 generations! I love science, but that took me some time to grasp. I had to think about it, and think about it, and think some more. Then there was the concept of a billion years, a length of time 1,000 times as great! Now I am comfortable with such quantities, but it took work. Most people I know are not comfortable with deep time. In particular, the majority of religious Americans firmly believe that the Earth is no more than 6,000 to at most 10,000 years old, and that the first humans were created within a few days from the creation of the universe.

By the end of the book it became clear that the author's heart was in the ignorance of and opposition to the theory of evolution, particularly the idea of human evolution or human origins as anything other than direct, instantaneous creation by God. Very few writers properly distinguish the fact of biological evolution—that it did happen, that life has changed through time—from the theory of natural selection, which is the mechanism of biological evolution. When we say "theory of evolution" we mean the theory of natural selection. It is likely that most scientists, along with nearly all the public, conflate the fact and the mechanism. Fortunately, Dr. Shtulman distinguishes them, though not as clearly as I might have hoped.

To "get" evolution, one must know a great many things, including that many species are now extinct, that all life on Earth is based on DNA, and that there has been life on Earth for many millions of years, even several (3.8-4) billions of years. Without that foundation, all talk of evolution is a castle built on air, and is fruitless. Then, to "get" natural selection, one must know several things further, in addition to the facts of evolution, primarily that the offspring of one pair of creatures differ a little from one another in small, random ways; that not all those offspring will have offspring of their own; and that small differences in the DNA of that set of offspring lead to differences in how well they can grow, thrive and reproduce. Further these small differences naturally occur and over many generations and great spans of time, small differences in the health and reproductive ability among creatures of the same species add up to significant differences in the range of characteristics to be found throughout the individuals of that species.

Very, very few people willingly do the work to learn all those things. In a very real sense, then, most people have no right to an opinion about evolution! They don't have the mental tools to form a valid judgment. Sad to say, many of American society's decision makers are so ill-informed about every single branch of science that they have no proper basis to form valid judgments. But they write legislation that the American public must follow, upon pain of legal sanctions such as fines or imprisonments!

Well, I've chased that rabbit far enough. The subject of Scienceblind is fascinating. Unfortunately, all too frequently the writing is rather dull and I had to slog through it. I didn't skip any, but believe me, I was tempted to!

There was a time in both Europe and America during which a very popular form of entertainment was to attend science lectures and demonstrations by noted scientists. Scholars such as Michael Faraday and Humphrey Davy made much of their income from such lectures. It would do most folks a great deal of good to attend such lectures today. Those who are willing to watch programs such as Star Talk with Neil deGrasse Tyson and programs such as Nature and Nova get a little bit of what they need to "get" the underpinnings of modern science. But those whose eyes glaze over at such material have little hope of making valid decisions about topics, such as vaccination, that can lead to great consequences for them, their children, and for those around them.

Tuesday, June 06, 2017

The yellow-tipped little agate snail

kw: species summaries, natural history, natural science, museums, research, photographs

Earlier this year I completed two major projects to prepare about 17,000 data records at the Delaware Museum of Natural History for all the freshwater species of bivalves (clams and mussels) and gastropods, and load them to a new database system from which they can be served up via the internet. The principal portal is iDigBio. A secondary portal, from which it is easier to dig into the records on a museum-by-museum basis, is InvertEBase. Each project took about a year.

That done, I have begun working through the museum's data for terrestrial gastropods (land and tree snails), which total about 38,000 records. We decided to take these a cabinet or two at a time, for the most part. I am basically tackling between 1,500 and 2,000 records per mini-project. A first project took about a month, so I expect the sum of about 20 projects to take a couple more years, maybe three or more.

I am in the midst of inventory for three related families, and the first is Achatinellidae. These snails were so-named because they resemble the large tree snails of the family Achatinidae. The prefix "achat-" means "agate" in Greek, and refers to the striped appearance of the most familiar species, the giant African tree snail, Achatina achatina (Linné, 1758), also called the tiger snail.

The one shown in this image may have a shell as long as 8" (20cm). The suffix "-ell" means "small"; the snails of family Achatinellidae are much smaller than the Achatinidae, but many have a similar striped look.

The type genus (the one the family's description is based upon) is Achatinella, and the type species is Achatinella apexfulva (Dixon, 1789). As I was taking inventory of the specimen lots of this species, I noticed that some had been collected by a major donor to the museum, Munroe L. Walton, when he was quite young, not more than eleven years old. In the three photos below, you can see they were collected in Hawaii in 1901; Walton was born in 1890. First, the photos, which mostly speak for themselves. Commentary continues following.

Around the year 1900 it was common to distinguish the many color variations of variable species by assigning subspecies names. The original labels for the first two lots reflect this. The third lot was originally attributed to a different species because many of the shells in certain parts of Oahu are left-handed, such as the one on the right in the third picture. These are now recognized as part of the species apexfulva. The suffix "-fulva" means "yellow", and shells of this species have a yellow tip. Specimens of this species grow to 1.5-1.9 cm (0.6-0.75 inch).

The second lot shown has an added label, written by Edward W. Thwing, who may have been the actual collector of that lot or part of it. He was 22 years older than Walton. The designations "New." and "Newc." on some of the labels refer to Wesley Newcomb, a physician who became a curator of mollusks at Cornell in the 1870's and until 1888. He described the first specimens of many species in the family Achatinellidae.

Although Achatinella apexfulva does not have a common name, I call it the "yellow-tipped little agate snail" as a direct translation of its scientific name. The Achatinellidae in general are colorful and attractive. Sadly, most, including A. apexfulva, are now extinct.