Wednesday, March 30, 2016

Bugs on the side

kw: natural history, museums, collections, photographs

The Delaware Museum of Natural History is primarily known for mollusks (mainly sea shells but also squids and their relatives) and birds. That is what it was set up for. But every natural history museum winds up amassing collections of all kinds. Today I happened across a few cabinets of insects. There is a set of covered drawers that hold the cataloged specimens, but nearby are a few cabinets containing donations that have been received but are not yet processed (except for the freeze-thaw-freeze pest extermination part).

For your delectation, here are two photos of small cases as they came from the donor:

These are large moths. At the top, from left to right, familiar species of North America: the Cecropia, Luna and Polyphemus moths. The large specimen in the center is the Birdwing Moth or White Witch Moth of Central and South America, the largest in the world at 11 inches across (28 cm). I don't know what the lower three are.

These are cicadas. The familiar "17-year locust" cicada of North America is represented by the bottom three specimens. The three larger ones are from other parts of the world. Considering how clumsily the local cicadas fly, I'd hate to have that big one come bumbling into me at high speed!

I took these photos on cabinet trays, and had to shoot at an angle to avoid reflections from ceiling lights.

Sunday, March 27, 2016

The Roach Motel for everything

kw: book reviews, nonfiction, physics, black holes, history of science

In 1905 Albert Einstein published four small monographs in scientific journals. Their subjects were

  • The Photoelectric Effect, in which the color of the light, and thus its frequency, were directly related to the voltage of electrons emitted from a sensitive surface, and depending on the "activation potential" of various surfaces, there was a threshold below which no emission could occur. This proved that light is quantized as particles now called Photons.
  • Brownian Motion, in which tiny, lightweight items such as pollen grains, suspended in water and viewed through a microscope, are seen to jiggle continuously. He showed that this is a statistical effect of jostling by molecules of water, the first empirical evidence for the existence of atoms and molecules.
  • Special Relativity, in which he established that the speed of light and all effects of the interaction of light with spacetime are the same as measured in any non-accelerating reference frame, regardless of that frame's velocity with respect to any other. This implies that everything except light is variable when measured between reference frames moving at differing velocities, particularly mass, length, and the passage of time.
  • Mass-Energy Equivalence, expressed in the formula E=Mc², in which he showed that Maxwell's laws imply that as energy is added to a system its mass increases. The parameter c is a large number, 300,000 km/s, and its square is thus so huge that simply heating a kg of iron, for example, between 0°C and the melting point of the iron, will only increase its mass by something like a few billionths of a billionth of a gram. But the equation as stated provides a hint, later well defined by the scientists of the Manhattan Project, that nuclear reactions which confer a reduction of mass yield enormous energy release.

Guess which of these discoveries led to Einstein receiving the Nobel Prize in 1922? It is the Photoelectric Effect, which laid a foundation for Quantum Physics, by effectively discovering the Photon, the first quantum particle to be so defined.

Ten years later, Einstein published articles on his General Theory of Relativity, usually just called General Relativity, which extended Special Relativity to accelerating motion and, in particular, to motions in a gravitational field. The set of equations at the core of the theory show that gravity is a consequence of curvature in spacetime caused by mass. As John Wheeler states it, "Mass tells Spacetime how to curve, and Curved Spacetime tells Mass how to move."

It wasn't long before scientists, striving to find exact solutions to the theory's equations, determined that the end point of gravitational collapse was a singularity. This had been hinted at by scientists as far back as 1783, when John Mitchell first calculated the mass needed for a Sol-sized star to prevent the escape of light, and thus be rendered invisible to a (safely) distant observer.

The events along the way between 1783 and 1915, and those since, form the structure of Black Hole: How an Idea Abandoned by Newtonians, Hated by Einstein, and Gambled on by Hawking Became Loved by Marcia Bartusiak. The author's aim is not to discuss the physics of black holes to any great extent—though a certain amount is necessary—but to trace the history of the idea, from an idea that made classical physicists queasy to the modern understanding of the way black holes have shaped the universe. That "queasiness" led to general relativity being neglected for most of fifty years. Finally, improvements in astronomical instruments and methods forced recognition that such "supercollapsed" objects as black holes might indeed be real.

The first astronomical object to be generally accepted as a black hole is Cyg X-1, in the constellation Cygnus (the Swan), which weighs about 15 times as much as the Sun. It and a blue supergiant star orbit one another closely, with a period of 5.6 days. The supergiant sheds mass in irregular fashion, and some of the gas is drawn into an accretion disk circling the black hole, where frictional and compressional heating raise temperatures to millions of degrees and cause flashing and flickering at primarily X-ray wavelengths. Such a black hole is called a "stellar black hole" because it formed from the collapse of a single star.

A much larger event or series of events must underlie the formation of the very large black holes at the centers of galaxies. It is very likely that a "supermassive black hole" is at the core of every galaxy. The stars in our own galaxy, the Milky Way, orbit a black hole with a mass of about 4 million Suns, or about 270,000 times the mass of Cyg X-1. Larger galaxies, or galaxies with larger central bulges, and large elliptical galaxies which are all central bulge, have central black holes up to several billion Suns in mass.

Do these galactic black holes also shine or flash like Cyg X-1? Whenever they have a source of infalling matter, they do. Quasars are extremely bright and very tiny (compared to a galaxy) objects that are seen in light, radio, and X-rays caused by large amounts of matter in their accretion disks. "Active galactic nuclei" are dimmer than quasars, from our perspective, but are probably quasars when seen from a special perspective, because the emissions of black holes are directional.

Black holes all spin, and they all have magnetic fields. This is because they were formed from spinning matter (and accretion adds to their spin), and all plasmas in space are magnetic; the magnetic field is retained after collapse within the event horizon. Accreted matter, heated to a plasma, is spun by the spinning magnetic field and is compressed into a pair of jets which emit primarily along the spin axis of the black hole. A quasar is what we see when we are looking "down the barrel" of one of these jets. An active galactic nucleus is seen when we are off to the side. Cyg X-1 is apparently also pointed right at us.

When we read of a quasar that has an apparent brightness of trillions of stars, we must remember that the "trillions" figure is calculated by assuming equal brightness in all directions. The actual beam is a degree or two across, and a sphere has an angular area of more than 41,000 square degrees. So the "trillions" become "billions" or "hundreds of millions", nearly all concentrated into those two beams and so amplified from our viewpoint. That is still really, really bright!

The first quasar had a spectrum too weird to fathom, at first, until it was finally realized that the spectral lines were those of hydrogen, shifted far toward the red end, implying a cosmological distance of about 2 billion light-years. The distance to a quasar is actually rather tricky to calculate, because of three effects (this is just me now; the second and third factors are not mentioned in the book):

  1. The cosmological red shift caused by the expansion of space.
  2. The gravitational red shift caused by the tremendous gravitational potential close to the event horizon (where the gravitational red shift would be infinite!). This increases the total red shift and by itself will cause us to over-estimate the distance to the quasar.
  3. A blue shift caused by the relativistic velocity of the superheated matter beam, which might be as much as 0.2c to 0.5c pointed toward us, and perhaps even more. This counteracts some of the red shift from expansion and gravity.

Of these three factors, it is generally considered that the first is the greatest, but I have not read a definitive analysis of the second and third factors for any particular quasar…and I've been looking.

The book is fascinating and enjoyable. A timeline in an appendix helps tie events together, and traces the contributions of many scientists to the understanding of general relativity and gravitational collapse and its implications. A well-researched and well-written book, it rounds out the scientific story into a fascinating human story.

Friday, March 25, 2016

More about specimen labels

kw: natural history, natural science, museums, research, labeling, photographs

The current name of this critter is Leptoxis carinata (Bruguière, 1792), sometimes called the Crested Mudalia. Most folks call these and many of their sister species "little brown mud snails". Just like most birds are "little brown things" like sparrows and wrens, and most mammals are also "little brown things" like mice, voles and shrews, small dim-colored, unpretty shells dominate the world of mollusks.

Today the species takes second place to the labels. I've set this to show at a pretty large size so the labels are about natural size on most monitors.

Many shell collectors are like Mrs. Mumford, and add variety to their collections by trading or purchasing shells. In this case, however, after Isaiah Greegor died in 1894 his entire collection was sold to Henry Mumford. Upon his death in 1906 the collection was bequeathed to the Brooklyn Institute, to be named the Phebe L. Mumford Collection.

Like any good museum, they traded around, to gather and disperse variety, and a number of the Mumford specimens came into the hands of John D. Parker of Philadelphia. His collection was one of several large collections that were brought together under the curatorship of R. Tucker Abbott to jump-start the shell collection of the Delaware Museum of Natural History in 1971. I daresay that the script on the older label is Mr. Greegor's, and that on the Mumford label was done at the Brooklyn Institute in about 1907.

It is fortunate that shell collectors do not only "go for the gorgeous", but also collect for variety and scientific completeness, and thus the "little brown things" of the world are not neglected when developing natural history collections.

Wednesday, March 23, 2016

A nemesis of museum collections

kw: natural history, natural science, insects, museums, research, photographs

Behold the dreaded Carpet Beetle. This species is the Varied Carpet Beetle, Anthrenus verbasci Linnaeus, 1767, the bane of natural history collections everywhere.

The adult beetle, seen at left, is typically less than 3mm long, and can be as small as 1.5mm (1/16 inch). The larvae are larger, to 4mm long. The two molts at right are typical of what we find when something organic, such as remnants of a dried snail or clam left in a shell, has been eaten. I've never seen living larvae, just their molted skins, and it is rare to find an adult beetle that has died in the shell box. Most frequently, a couple of molts and a lot of "frass", or dustlike beetle feces, are the only indication that a specimen's flesh has been consumed.

This is a species of "dermestids", members of the family Dermestidae, which also includes a group called Hide Beetles, because they are efficient consumers of leather and traces of meat. A natural history museums typically keeps a colony of Hide Beetles to use for de-fleshing skeletons. There is no better way to remove all soft tissues from the bones. I suppose that Carpet Beetles could work as well, but by using a larger beetle, they are better able to keep them contained in the "bug room"!

I recall one day a couple of years ago coming in to the research section on a Monday, to an awful smell. The curator of birds and mammals was there, cleaning up after a freezer that had broken down over the weekend. Most of the contents of the freezer had been small birds and smaller mammals such as mice, undergoing the usual treatment for pests before being skinned or otherwise prepared for storage. They were sufficiently freeze-dried that they didn't rot too badly over the weekend. A beaver carcass was another matter!

The beaver weighed 30 pounds, and the curator asked one of the volunteers for the day to help her prepare it. Wearing masks and gloves, they took it to the lab, returned to finish cleaning up the freezer room, then went to work: they skinned the beaver carefully, refreezing the skin until they could prepare it as a specimen; they removed and discarded the organs and cut most of the flesh from the skeleton and discarded it; then they carefully cut the skeleton into pieces "for the bugs". Only a portion at a time was put in the dermestid chamber, so as not to overwhelm the larvae. Portions not in the chamber were kept frozen. Eventually, they had a study skin, preserved and cotton-stuffed, and a beaver skeleton fully cleaned and washed and ready to be put in the collection.

Managed carefully, beetles and their larvae are quite useful. They're only a pest when they get somewhere you don't want them.

Monday, March 21, 2016

The Spiny River Snail

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

It seemed like months since I've worked with a snail that was "snail-sized", that is, an inch or more in size. The Spiny River Snail of Tennessee, Io fluvialis (Say, 1825), has a satisfying heft to it. It is endemic to the Tennessee River and its tributaries, particularly clear, fast-flowing, well-aerated rivers. The species name fluvialis indicates this. I prefer species names that are descriptive, rather than those that are named for someone, though biologists do like to honor special friends of theirs with species names.

Older collections of this species include members from all up and down the Tennessee Valley system, but after 1932 large portions of the rivers were dammed up by TVA and later projects, and became stagnant. Specimens are now found in comparatively few locations.

As befits a fast-water snail, it has a chunky, substantial shell. The spines probably have two functions: firstly, to help prevent rolling, and secondly, to discourage predators.

A few shells in our collection are as long as 6 cm (2.4 in.), but most are 3-4 cm or smaller. This first image shows two nice-looking specimens that were probably collected in the 1950's. If I knew who R.H.T. was I'd have a better idea of the time period.

The labels show a few misspellings. The donor to the Delaware MNH was Thelma Crow; "Crowe" is incorrect, but I have seen it on many of the labels for lots donated by her. The volunteer who entered the data for one group of Mrs. Crow's shells messed up, most likely by hearing the name but not seeing it. Then, Mrs. Crow herself doesn't know how to spell "label", as we see on the older label that came with these shells. Finally, to resolve the town's name, Rogerville or Rogersville, I consult an atlas to find that Rogersville is correct, as seen on the label by the mysterious "R.H.T.".

This image shows specimens collected in the Clinch River in Virginia. Clinchport is about 20 miles upstream of the VA-TN boundary. These shells show some of the range of variation of spine length, from quite pronounced to nearly not there. Variations such as these led early authors to describe at least ten species in the genus Io, but all are now considered the same species. I don't know why this genus was named Io; the name refers to a mortal woman who was seduced by Zeus in Greek mythology.

The old label that came with this lot states "Io etc.": it was in a box that contained more than one species. Other lots in the collection taken from the same box contain a copy of this label. This illustrates one aspect of museum collections research, that as much as possible, we try to trace the source of a specimen in location and in time. In this case, we have a location, within a mile or so along the Clinch River, but when these were collected is unknown and is only delimited by the date on which Mr. Parker gave or sold his collection to the museum, in the 1970s.

These images inside the aperture of the larger shell above show traces of its history. If we know enough about the numbering schemes of collectors we can infer who owned this shell along the way. The designation below, which I deciper as "[2092 C.M.]" probably refers to the collector. A later owner inked on the opposite side "11552", and this was probably Mr. Parker. I don't know if the brackets are his, or if they were added when someone at DMNH wrote the newest number, 131405. Our standard practice is not to bracket old numbers, but to put a single horizontal line through them, so they can still be read, but are clearly obsolete.

If a researcher wants more data on this shell or lot than we have recorded in our database, it is often possible to go to the donor's notebook, which the museum frequently has in its library.

This image shows the rather overcrowded box of 15 shells that the specimens above reside in. I share the proclivity to try to save space, but the museum's cabinets are less than half full, so we don't really need to be this anal about it. I may yet decide to replace this #4 box with a #5 box, which is 1.5 inches longer.

I tried out a small size plastic box, which is 3x3.5x1 inch, but it would only hold half the shells. Their spiny shape makes them take up a lot of room. The next size plastic box is much taller, so the #5 paper box is more appropriate.

This final image shows a lot of 13 shells of a subspecies recognized by some. The original label from U. Michigan's Museum of Zoology has "f. brevis" after the species name and author. This is a "form" name, which here indicates the shells are a little shorter for their width than is usual for this species.

These shells were collected 5.5 miles downstream of Kyles Ford, TN in late summer, 1924, so there were no mainstem dams on the Clinch River yet. To date, the portion of the Clinch near and below Kyles Ford is not yet dammed up, and a new dam that would stagnify the area is not planned, so perhaps this subspecies is still to be found there.

These labels show the chain of ownership: collected for Michigan by Wm. Clench and P.S. Remington; and Michigan probably split a portion of a larger lot for the benefit of the Kansas U. museum, which later sent DMNH their lot; we have no record that this is a further split. However, considering that one of our lots contains 100 of these shells in two 3"x6"x2" plastic boxes, it may be that Kansas U. retained half or more of the shells they got from Michigan.

Sunday, March 20, 2016

Are you an Econ? Don't bet on it!

kw: book reviews, nonfiction, psychology, economics, errors, behavior, behavioral economics, memoirs

John Maynard Keynes developed early theories of economics and markets, and made a distinction that later economists neglected and then forgot. He stated that the actions people take are frequently prompted by "animal spirits", which he defined as "a spontaneous urge to action rather than inaction, and not as the outcome of a weighted average of quantitative benefits multiplied by quantitative probabilities." [Keynes, 1936: The General Theory of Employment, Interest, and Money] In other words, people do not always, or even usually, thoroughly calculate or deliberate upon their decisions.

Fast-forward forty years, from 1936 to 1976. Milton Friedman has become the twelfth Nobel laureate in Economic Sciences. Economic theories have been developing, even proliferating. Men (no woman won until 2009) labored for years to wring a new formula out of the growing mass of theory, a few became Nobelists, and the edifice thus built was indeed founded on the analysis of "quantitative benefits…" and so forth. Social scientists other than economists were beginning to protest that the "rational" decisions that were required for economic theory to work could not be realistically made by genuine human beings. Policies were arising that assumed everyone was capable of making near-instantaneous decisions using the very calculations that Nobel Prize-winning economists had labored for years to discover.

Friedman poured oil upon the roiled waters by invoking the "as if" argument, using an expert billiards player as an example. To summarize, an expert, or even pretty good cueman, does not calculate the outcome of a series of Newtonian physics collisions, but plays as if such calculations had been made. But others, who for the time being mostly kept their thoughts to themselves while they sought tenure (!), realized that this implied all of us have Olympic-level skills when we make economic decisions. Don't I wish!

One of these others was Richard H. Thaler, who began to use the term "Econs" to describe the fictitious super-rational beings (who could out-Spock Mr. Spock) upon which economic theory depended. He distinguished Econs from Humans, a term referring to genuine human beings, who are indeed not Vulcans, but have emotions, proclivities, life histories, and only in the most extreme cases act with unvarnished Reason. Econs never err. Humans seldom fail to err. Extracting useful theories from the reliable errors of Humans has been a major element of Dr. Thaler's work, as described in his memoir Misbehaving: The Making of Behavioral Economics.

Dr. Thaler might be a somewhat unusual economist, because he has befriended and worked with a number of psychologists, including Daniel Kahneman, whose book Thinking, Fast and Slow I reviewed a few months ago. Perhaps most economists fear too much exposure to psychology, because Humans are so complex. Yet it is that very complexity that must be studied, for policy that does not take it into account cannot succeed.

The main "policy" way to get people to do something is to tell them. If the matter is important, perhaps sanctions such as fines will be enacted. A simple example might be (Ladies, avert your eyes) putting a sign in the Men's Room, above the urinals: "Please Aim Accurately. Excess Cleaning is Costly". Such a sign is likely to result in even greater need for cleanup. What to do? Economics is the study of incentives as one aspect of motivation. What motivates Human males? Exhortations typically just rile them up. Of course, if there were no Humans, only Econs, no sign would be needed. Econs never miss. Humans seldom miss if they have an enticing target. Some years ago in Holland something new was tried: to etch the image of a fly just above the drain of the urinal. "Excess Cleaning" needs were reduced by 80%. Don't be surprised if you see a "fly" in a public urinal.

The title Misbehaving refers to anomalies that Dr. Thaler has been collecting for decades, anomalies that could not exist or persist if we were all Econs. The fly-target is just the simplest example. Others include violations of the "Efficient Market Hypothesis" (EMH). The most glaring is a case in which 3Com acquired Palm, then years later sought to divest it by a partial sale of stock, to be followed by successive sales until the whole was sold off. Early sales of Palm shares indicated that, if EMH were true, investors considered the residual value of 3Com to be negative, because the value of all Palm stock at that price would exceed the value of the combined company! This is a small example of a bubble. The existence of bubbles, such as the U.S. housing bubble that burst in 2008, is a huge anomaly contrary to EMH. Bubbles imply that things are wrongly priced, and so does all the talk on morning "business segment" shows about whether a "correction" is imminent. Econs never suffer bubbles or corrections. For them, the price is always right. Always. For Econs, the price they are willing to pay or receive for an equity exactly mirrors all the expected future value of the company and its dividends and even closure costs when it comes to an end. Econs are the ultimate Seers!!

Maybe at work you have access to a 401(k) retirement savings plan. Do you contribute? Does your company pay a matching contribution of the first few percent? For years, taking advantage of a 401(k) required filling out some paperwork, selecting a level of participation, and perhaps selecting one or more funds (including company stock and a few mutual funds) to put your money in, for the next 20-40 years. Making changes was not simple. Participation was low.

I guess I am more of an Econ than usual. I jumped at the chance, starting with 6% (which we could barely afford to sock away, but the company matched the first 6%, so it was like getting free money). Each time I got a raise, I added a percent or two, until I maxed it out. But I knew one guy who put in his 6% each year, but took it back out the following year and spent it. He got his free money, but was only accumulating half as much as someone who saved 6% and left it there with its match. I bet he wasn't nearly as well prepared to retire at 66 as I was. Even more puzzling, in those years, even with 3% or even 6% company matching, more than half of my co-workers never started their 401(k).

A dozen or so years ago, Dr. Thaler and others began convincing companies to switch from this opt-in method to an opt-out one. Employees were informed they would be automatically enrolled in a 401(k), with 3% of their earnings and 3% of company matching funds going into some default investment, usually a money market fund or company stock or a mix of both. If they really didn't want it, they had to sign a certain form and send it to the payroll office. Participation rates increased greatly. Then they devised a follow-on program called Save More Tomorrow: Each time an employee received a raise, half of it (or a different proportion that could be chosen) would be added to their participation rate, maybe raising an initial 3% to 4% or 5%, then to 6% after the next raise, and so forth, up to a ceiling such as the maximum allowed amount. Some companies, not wanting to write extra software to couple the payroll system with the retirement system, opted instead to simply add half a percent yearly to each participating employee's savings rate, unless, again, they sent in a form with differing instructions.

If you have access to a plan such as this, and it has resulted in your saving more toward retirement than you used to, you have Dr. Thaler and other "economics renegades" to thank. Reading such an entertaining, informative book, I was quite encouraged that, finally, some economists are looking at us as genuine Humans, who do things because we like to rather than because of some lengthy, Nobel-worthy calculation; who make decisions when we are happy or sad or mad that are often different from what we'd decide in a calmer mood; who wear green today and blue tomorrow and can't decide what color shirt to wear after that, so we ask our spouse, who likes mauve but we hate it so we grab an apricot-and-chartreuse print and wear that. Don't be surprised if the decision which house or car to buy is backed up by no more thought than that print shirt! We are Humans!!

Thursday, March 17, 2016

Incoming at the Museum

kw: natural history, natural science, museums, research, collections, photographs

A few weeks ago a new donation was brought to the Delaware Museum of Natural History, the shell collection of a Mr. King. It consisted of a dozen or so glass-topped drawers of shells in boxes. The curators and Alex the collection manager for mollusks cleared out some space in a freezer, and in they all went.

All specimens brought to the museum are frozen, thawed just long enough for insect eggs to hatch, and frozen again, which kills all the pests that might have arrived with them. I have seen boxes that had been stored in a humid basement for decades, that brought in the usual array of basement critters—crickets, spiders and roaches—plus, no doubt, such subtler creatures as carpet beetles.

I remember my butterfly collection, assembled when I was between 10 and 13 years old. I spent a lot to buy shallow glass-topped boxes, stuffed them with cotton, and put butterflies in artistic arrangements. Within a year or two, all the bodies, and parts of some wings, were eaten by the larvae of carpet beetles. I found out the hard way why insect collections are pinned and kept about an inch above the substrate, and are best kept in cedar-lined trays. Many mollusk shells, particularly when the animal was captured alive and dried, have if not the dried body, traces of "meat", which is relished by the tiny larvae. Of course, in a sense, the larvae do you the favor of destroying all traces of soft tissue, leaving only the shell, and of course, their "frass" of dust-like droppings and cast-off molts. Museums don't consider that a "favor". Traces of tissue can later have their DNA analyzed, which is being done more and more frequently as the cost of the process drops.

So, into the freezer with the whole collection!

A couple of days ago the de-bugging operation was complete, and Alex spread all the drawers out on the tops of low cabinets to sort through. I managed to get a few pictures before all the specimens were re-assembled into new boxes and trays with new DMNH labels added.

In the order I took them:

First, a drawer of chitons and tusk shells. Chitons are mollusks with eight shells held atop a sluglike body. The largest one at the top of the image is about six inches long. Tusk shells, or scaphopods are small; a few boxes of them are at left and top left. They are hollow with a hole at each end; they are like tapering tubes.

Second, twelve of the drawers laid out atop several cabinets. The glass has been removed from the drawer at far right, which is the one pictured above, holding the chitons and tusk shells.

Third, a drawer of bivalves, mostly of the kind we call clams.

Fourth, a closeup of two of the bivalve specimens, single shells from two different clams, one from the Middle East and the other from China. They are of different species in the genus Circe. I took this picture to show the labels that the collector, Wilbur L. King, had pre-printed and hand-filled out. It seems nearly every collector comes up with a slightly different way of making labels. I am almost tempted to gather examples (photos) of as many different label styles as possible! Almost…

This also shows that Mr. King was either a world traveler or traded with collectors worldwide, which is a popular means of obtaining a great variety of specimens.

Each of the drawers contained 40-50 specimen lots, so our Alex has had his work cut out, preparing fresh boxes (acid free) for them all, either entering them into the mollusk database or supervising volunteers to do that, and printing DMNH labels for them, and then putting them away. He gets a lot of walking done! I suspect if he wears a FitBit that he has no trouble getting in 10,000 steps or more daily.

Sunday, March 13, 2016

Finally! Some genuine Science Fiction

kw: book reviews, science fiction, space fiction, space flight, space aliens

John Campbell's recipe for a good short story (SF or not, but especially SF): "Pose a problem, and then solve it." The corollary for writing a novel: Do it 25 times. There was a period of a few years that I read a science fiction book, either novel or collection, almost every day. Then the genre began to change, and eventually even Isaac Asimov began to write more about sex than about science. "Hard SF" of the kind that characterized the Golden Age vanished. Fortunately, that couldn't last forever. For the past couple of decades, even as the library shelves formerly filled with speculative fiction were being taken over by sword-and-sorcery fantasies and post-apocalyptic dystopias, a few writers have been returning to imaginative technology as fodder for their work. I am thinking of post-1990 books by Stephen Baxter, Catherine Asaro and Ben Bova, for example.

This week I made acquaintance with work by an author new to me, John Sandford, and his collaborator, Ctein. The book is Saturn Run, and it is full of good ideas that are backed up by good science. I'll leave it to others to comment on how well the geopolitical US/China conflict is depicted. Geopolitics runs along a dimension I cannot "see". Among the new ideas, these stood out to me:

  • A type of ion engine called VASIMR, VAriable Specific Impulse Magnetoplasma Rocket, has been on the drawing board for a while, and small ones were tested some time ago. Scale 'em up from a few watts to a few GW per ion beam, and you have a way to slowly thrust a vessel weighing a few hundred tons up to the kind of speed that can cross 1.4 billion km in a year or less. Let's see, 1.4 billion km / 31.6 million seconds = 41 km/s average. The authors ramp up to about 140 km/s and back down again, covering the distance in more like nine months. The "Variable" part is the genius of the engine. High velocity exhaust = high specific impulse, but has a poor momentum-to-energy ratio for accelerating from a stop to the "lower" velocities, less than a few km/s. So you get more oomph at the low end when starting out, and better high-end acceleration by ramping up the exhaust velocity as the ship accelerates.
  • Conversion of electrical energy to thrust is stated as "not quite 50% efficient". Maybe by the year 2066 they'll be able to do better than the thermodynamics of Sadi Carnot, which fix a limit of 40% efficiency for any thermal-to-thrust system. Anyway, if you are using 8 or 9 GW to thrust the ship, you have another 9 GW or so of waste heat to dissipate.  In space, radiating heat away is the only option. A phase-change liquid-metal scheme, and certain ancillary tricks, serve to make a radiator that runs at 600 degrees and is "only" the size of a couple of football pitches, rather than the size of Chicago.
  • First Contact is not with the aliens themselves, but with a conversational AI that can proctor certain trade deals to allow humans to obtain a limited amount of alien technology. This includes methods of making and safely storing usable amounts of antimatter for the next spaceship generation. Interestingly, the galactic civilization the authors present bases contact between species on proctored trade deals, strictly avoiding interspecies contact. It seems they learned the lesson that we have yet to learn from our own history of inter-cultural contact!
I did find myself wondering how much plutonium they'd have to carry to run a 20 GW nuclear reactor for a couple of years. The words "nuclear waste" never appear, but I suppose it was wise to put that issue off to a very different kind of novel.

Of course, science fiction is not just about purely technical matters. People are immensely variable, and authors play characters off one another regardless of genre. I was particularly impressed with the well rounded characters in Saturn Run. Sanderson and Ctein created characters that a reader cares about and feels for. I admire this in a writer. I've tried to write fiction, and found I have no proper feel for creating characters that are believable, likable, or that can induce empathy in a reader. The most sympathetic, at least to me, is a central character, Sandy Darlington, a paradoxical and hiddenly broken man, who manages to think of things nobody else remembered to take account of.

If I go on any more, I'll introduce spoilers. If you like SF that emphasizes science, yet with eminently human characters (even the AI!), this is for you.

Friday, March 11, 2016

The Bigmouth Rocksnail

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

As I look through all the various species of freshwater snail, particularly in the family Pleuroceridae, I get the impression that most of them can be found in the Coosa River of Alabama. It is a biggish river, some 280 miles long, beginning near Rome, Georgia and flowing into the Alabama river north of Montgomery. It is warm enough, and sufficiently low in pollution, to host hundreds of freshwater mollusks, including dozens upon dozens of river snail species. However, saying it has low pollution may no longer be accurate, as we will see below.

In early days of collecting, a genus was a pretty broad category, and this only began to change in the 1940's as naturalists labored over the rapidly growing "tree of life" they'd been constructing since 1758 when Linnaeus proposed Binomial Nomenclature. Large collections supported more and more precise research efforts, and the ever-shifting see-saw between "lumpers" and "splitters" swayed definitely toward the splitters. After all, naming a new species—or naming a whole raft of them—was the most common way for a naturalist to make a lasting impression. At present, the extrema of the distribution of likely species in the family Pleuroceridae (see the prior post for more on this family, and this Wikipedia article) ranges from 21 species to more than 300. But when Daniel L. Graf sought to organize all the known species in this family, he called the labor "The Cleansing of the Augean Stables" (this link downloads a large PDF of his monograph, published in 2001), because there were about 1,000 "nominal species", just in this family. Clearly, some lumping has occurred since his work, more or less depending on which authority you trust most.

Among the species in the "middle of the alphabet" of those assigned to either Elimia or Goniobasis, I came across one that I was pretty sure didn't belong. So I spent a pleasant couple of hours trawling the online collections of several museums. The original label, which is in the handwriting of the collector, H. H. Smith, contains a clue, in someone else's script. The scrawl at the lower left on the brownish label reads, "Anc. occultata Smith". The same hand numbered the label "53089" at the upper left. I don't know who this person is, but someone else must have owned it for a short while, because the more recent label by C. L. Richardson has a different genus and a misspelled species. He numbered this specimen "17435" for his own collection. Smith's number had been "7083", and now the DMNH catalog number is "80433" (Yes, all of this is important).

The species Anculosa occultata Smith, 1922 has been renamed Leptoxis occultata (Smith, 1922). I checked the online data from several museums before finding one that had photos of their specimens of various species of Leptoxis, including occultata. Sure enough, these shells matched that photo the best, and agreed with the description by Smith; I looked that up also, on BHL, the Biodiversity Heritage Library. The next image is Figure 22 from that reference, but in the text, the description refers to Figure 21, which is a typo, for that figure is clearly much different, while Figure 22 matches quite well.

We see here Figure 22 and a closeup of the shells in our sample. All lines of evidence taken together convinced me that this lot was indeed properly identified by the person who wrote on Smith's label, and that someone (probably not Richardson, but more likely another collector who possessed the lot just before him) incorrectly re-identified these shells as a Goniobasis species, and misspelled the species name. Richardson would have copied that identification, as did the volunteer at DMNH who wrote "our" label in 1972. At least the volunteer was able to see that what Richardson had taken for the word "Baz" was instead "Bar", making it easier for us to determine where the shells were collected.

"Leptoxis" most likely means "small and sharp", and the genus as a whole consists of smallish shells, mostly with sharp apexes, though this species is more blunt. "Occult" means "covered", alluding to the way the aperture in some specimens is large enough to nearly hide the rest of the shell.

It is likely that going to "The Bar" on the Coosa River to have a look for these would prove fruitless. This species is listed as Extinct in the IUCN Red List. Loss of habitat, meaning in this case, loss of water of sufficient clarity, is the primary reason.

DMNH has just this one lot, collected by Smith, apparently in the 1920's. We are unlikely to obtain another, except perhaps in a trade or purchase, because the investigators who performed a survey in 1996 could find none.

I guess to most people, the extinction of a little river snail, no bigger than a marble, is no big deal. It isn't a warm, fuzzy (or feathery) critter with soulful eyes. But to me it is rather sad.

Wednesday, March 09, 2016

The Virginia River Snail

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

In recent months I have been performing inventory of the freshwater gastropods (that is, snails) in the collection of the Delaware Museum of Natural History. A species that caught my fancy the other day is the Virginia River Snail, formally known as Elimia virginica (Gmelin, 1791). Another "common name" used for this critter is the Piedmont Elimia, but only by those who know what "Elimia" means.

Many species now in the genus Elimia were formerly classified in Goniobasis. "Elimo" in Latin means "to perfect", that is, to make complete. "Gonio" is from French for "angle, and "basis" has much the same meaning in both languages. There is much controversy, that has been going on for a generation or so, about which genus each of several hundred species actually belongs to. Some malacologists (those who study mollusks) believe all of the species of interest here belong in one of these genera only, some the other, but the majority are still working to define just what distinguishes one from the other besides affinity to this or that early author, or early ideas about geographical distribution.

The full scientific name of any species includes the Genus, the Species epithet, and a reference to the first scientific article in which the species was described. As it happens, many workers consider that the description by Thomas Say in 1817 more properly describes this animal, rather than the earlier one by J.F. Gmelin in 1791. Controversy upon controversy! Also, the parentheses are a code that the species virginica was originally described under a different genus. Thus many museums have this species listed under the label Goniobasis virginica (Say, 1817), and some still list it as Melania virginica Gmelin, 1791.

Species in the genera Elimia and Goniobasis, whether they are one genus or two, or some less fortunate combination, comprise the largest portion of the family Pleuroceridae. "Pleuro" comes from a Greek word for "side" or "flank", and "cera" means "horn", as a ram's horn. As presently described, all species in the family Pleuroceridae are native to eastern North America, from Florida to southeastern Canada.

Here is a typical box of E. virginica shells, 210 of them. The appearance of this unwashed lot shows why we informally call these "mud snails". They seldom exceed 3 cm in length, or 1 cm in the largest diameter near the aperture.

This is a typical high-spired shell. Pleurocerids are generally high-spired and rather heavily built. They don't have the delicacy of lake and pond snails.

This species inhabits major rivers from Connecticut to Virginia, where it was first collected. It is thought that the original distribution was exclusively in rivers that empty into the Atlantic, and that occurrences elsewhere are from various introductions. The DMNH collection includes lots from Connecticut, New Jersey, New York, Pennsylvania and Virginia, which are included in that region, plus Maryland, South Carolina, Tennessee, and West Virginia. Maybe the latter are introductions, or perhaps they were just found later than the others and were there all along. A known introduction is along the Erie Canal to streams flowing into Great Lakes.

Specimens from three lots are shown in this montage. The upper two photos show items added to the collection in early days, in the 1970's. The third came along later, though the collector named on the label was active about a century ago.

If you click on the image to see it full size, some differences among populations can be seen. The shells from West Virginia have a darker stripe along the whorls, and those from Tennessee have stronger growth-line decoration compared with the others.

The angled tip of the aperture opening shows a possible reason these were originally put in the genus Goniobasis. Whether they are sufficiently "perfect" to warrant the name Elimia instead, I'll leave up to the experts.

I am sometimes asked, "Why does a collector sometimes gather hundreds of the same shell? Wouldn't some smaller number be sufficient?" I passed this question along to the curator one day, and she said, "The more the better. Range of variation is frequently studied." In the box of 210 shown above, you can see variation in color and size, and even a little variation in shape (ratio of length to width, for example).

From a single specimen, or a very small number, you primarily learn that a certain species existed in a certain location at the time of collection, assuming this is not fossil material. From a larger number, and large numbers collected at various places and times, researchers can glean certain statistics. For example, if all you had was the six shells shown in this montage, it would be hard to determine that they actually represent the same species. With a few dozen or more from each location, it is possible to learn more about how a population varies, to see if there is overlap.

The largest lot, in numbers, that I have seen, contains 16,300 shells the size of grains of sand. Perhaps this is a little extreme. But lot sizes up to a few hundred are useful, if only because the variance of a statistic such as shell length can be more precisely defined from a larger number of measurements.

In the future I will have more to say about the information that we put on lot labels, particularly because this has been revised in recent years.

For further information about this species, begin with this Wikipedia article.

Saturday, March 05, 2016

Easier authorship

kw: book reviews, authorship, blogging, publishing

When I saw the title, How to Blog a Book: Write, Publish and Promote Your Work One Post at a Time, by Nina Amir, I thought it might refer to converting a blog to a book. That is something I've had the occasional idle thought of doing. However, Ms Amir has instead written of the reverse process: Planning a book, typically nonfiction, as one normally would for a hardbound volume, but doing the writing blog-style, in short posts. It matters which word you make into a verb:
Blogging a Book means you have a book in mind, and use blogging methods to produce the content.
Booking a Blog means you have a lot of content, perhaps on numerous subjects, and later convert some proportion of the blog's posts into a book. 
It is the latter process that I'd been considering. (I have some 1,900 posts in this blog already, and several hundred of them are not book reviews; I'd never dream of making a hardbound book out of hundreds of book reviews! But I have a few hundred thousand words of other stuff…)

Ms Amir's book is not a book about writing. If you are a writer, you already know how to write, and if you want to improve that, there are plenty of books, articles, classes, courses and coaches for that. Her book is about business. It is about the awful stuff writers hate, but have to accomplish if they expect their book to be professionally published, whether on paper or in e-book-land. Of course, you could self-publish, but it's extremely rare to self-publish a best-seller. A publishing company has all the departments already: Advertising, promotion, legal, logistics, and so forth.

The major portion of this book deals with getting together a business plan, a précis, perhaps an outline, and a few other documents that I've already forgotten, plus establishing a base, a platform, of online readership that can help convince a publisher your book is worth their while. It is a bit paradoxical: freely publishing your content in a blog seems to defeat the purpose. Why would your followers buy what you've provided for free? Fortunately, many people who like an author's work like to own it in a more tangible way than as a URL. But even more, there's content you don't put in the blog, including transition material and expanded content that is better written long-form for the publication. So once a publisher is on-board, you'll still be only about halfway there, but that's a lot farther than many authors get when faced with doing everything beforehand and then beginning the process of publication.

Nina Amir had a number of "ordinary" titles to her credit already, and she is not the first to use this process to prepare a manuscript and all the ancillary material needed to gain the attention of an agent and/or publisher. She is just the first to use the process to write about exactly that process. She published the first edition of How to Blog a Book several years ago. The volume I read is a "revised and expanded" edition. Naturally, she had more ideas later on. More particularly, aftermarket editions are one of several ways to produce more revenue from the initial book.

I have been experimenting with a vaguely allied process: Webbing a Book. I have read a couple of books that had multiple indexes, or multiple tables of contents, so the chapters or portions could be read in various orders depending on one's interest. Also, particularly for nonfiction, multiple indexes can make a book more useful as a reference volume. This is precisely the reason that the World Wide Web was created. Major online "chunks" of content can be indexed every which way, with the bits strung together as, well, a Web!

Thus, I began some months ago to write a book that could only exist as a web site. It has nine indexes. I am rather poor at planning a large project from end to end. I could never write a novel, and a full-size nonfiction book is an equally daunting prospect. I am an essayist, and do my best writing in blocks of 300 to 3,000 words. Depending on the type face and size a reader sets up, a "screen" is about 500 words. Thus the ideal length for the kind of mini-chapter I like to produce is 1,000 words or less. Going longer sometimes is probably OK. Once I get enough content that I am ready to make the site public, perhaps some folks who read it will provide feedback on that!

Here are a couple of pointers for anyone with a similar project in mind:

  • Think up as many indexes as you can to start with; adding more once a lot of content exists is tedious.
  • Pick a good template that lends itself to the form. I found one in Google Sites that has side navigation where I put the various indexes, and they are expandable.
  • As each item is written, hyperlink it back to as many indexes as are appropriate. Not every item in my site suits every index.
  • When several items form a series, link them with "next" and "back" links. But be sure that each item is linked into the hierarchy of at least one of the main indexes also.

I am a few months away from making it public. It is fun to do, and I hope people like it…at least some substantial subset of people! I don't plan to monetize it. A monetized web site needs some extra infrastructure to block non-subscribers from premium content. For many people who might like to create a reference book, a text, a memoir, or whatever as a hyperbook, the "flat" model I prefer will work the best. Besides, if your content is good and you get famous, there are other opportunities to make a bit of cash, from reworking some of it into a book-for-purchase to speakers' fees to becoming a coach or trainer in some discipline of your choice. Get famous, and more doors open.

Have fun!

Thursday, March 03, 2016

Natural History Museum Infrastructure

kw: natural history, natural science, museums, research

Just over three years ago I posted about my impending retirement, noting that I intended to volunteer with at least a couple of organizations. In mid-February 2013, I began to volunteer as a Historical Interpreter at the Hagley Museum. For a year or so I was there about weekly, but now it is more like monthly, for reasons I'll relate below—nothing bad about Hagley!

The second place is the Delaware Museum of Natural History. I began there also in February 2013, learning how to prepare specimen labels for the mollusks (seashells) and how to put away the lots in the cabinets. In a mollusk shell collection a "lot" refers to one or more shells that were collected at a particular location on a specific date. Usually they are in a box of appropriate size.

This image shows a tray of lots ready to be put away. These are all in boxes that fit into a space 3 inches (76 mm) wide, but there are plenty of mollusk species that must be put in larger boxes, and a few for which the five or so shells in the lot take up an entire tray. If you look closely, you'll see that while most of the boxes are paperboard, two are plastic boxes with lids, and also that smaller shells are put in a cotton-stopped vial in the lot box. Small numbers of the littlest shells are put in a gelatin capsule, and that goes in a small vial, in the lot box.

Over a few weeks' time, lunchtime conversation turned to what I'd done in my "prior life". When the curator and the collection manager learned that I knew something about databases, they immediately had a wholly different line of work for me to do! They were just beginning a project to change their database software from Access to a museum-oriented product called Specify, and they desperately needed help with that, and with the requisite data cleansing.

Here is a riddle: What is the difference between a Hoard (or more politely, an Accumulation) and a Collection?

The answer? The Index. An index is a database.

Here is what the original museum "database" looks like:

Some time in the 1980's they had a large enough contingent of volunteers, and an energetic collection manager, and were able to get nearly all the data in these ledgers into a DB5 database. I have found since that a major portion of one of the ledger books was skipped, but that is a tale for another day. After about 20 years, they had a software service company convert the DB5 database to Microsoft Access, which they were using when I began showing up.

The mollusk collection contains at least 250,000 lots and comprises about 2 million shells. I was asked if I could clean up the geographic data for about 15% of the collection, the land snails (formally terrestrial snails, such as garden snails and the large tree snails found in the tropics). This came to 38,000 lots. I did so in about two years of working, much of that at home, on data extracted to Excel. I learned a great deal about correcting misspellings and other anomalies and inconsistencies, and how to read handwritten labels in several languages!

This image shows a few lots and how they are arranged in a tray. The species Moulinsia fusca is a tropical land snail. The full name of a species also includes a reference to the publication in which it was first described: Moulinsia fusca (Gray, 1840). The parentheses indicate that fusca was formerly in a different genus but has been reclassified. The subspecies erythrostoma was described by Möllendorff, but we don't currently know the date he published it. The yellow label is the species header label for the tray. The pink label indicates that the lot with catalog number 135277 is a Paratype, and is located in the Type Lot Cabinet. This museum has a few thousand types, which are the specimens originally used to describe new species (Holotype), or other specimens collected with the holotype—one shell in a lot chosen as the exemplar—that help describe the variation in the species (Paratype). There are other sorts of Types, such as Topotype or Lectotype, which I have to look up when I forget their meaning.

In each lot box, earlier labels that came with the lot are kept under the new label created by this museum. Museums don't throw anything away! I frequently find information on the original label that didn't make it to the more recent label(s).

As I got more involved with the land snail project, I had to cut back my volunteering to Hagley to twice a month, then once. I love being a historical interpreter, but I love working with the shells even more.

Starting a year ago, the curator and several of her colleagues at other American museums received a grant to support data conversion of selected portions of the collection into Specify, mentioned above, which facilitates getting the data available on the Internet. I got the chance to do the same kind of work, and be paid! That's what I've been doing for the past year. I had finished the geography of the land snails in two years. As a paid contractor, I did not only geography but taxonomic reconciliation and correction/regularization of dates and the names of collectors, donors and other people, first for the freshwater clams and mussels, a smaller project of about 7,500 lots. Having finished those I am currently working with freshwater snails, with about 8,000 lots.

I have encountered many fascinating species, and decided that I'd present certain ones as I come across them, so from time to time I'll do so, and also continue to write about things that happen behind the scenes of a natural history museum.