Saturday, January 22, 2011

My Mother-in-Law Asks A Question


One summer morning, several years ago, my mother-in-law settled herself on the couch in my cottage and began tracing some of those time-worn conversational paths so familiar to people who have known each other for decades, those comfortable conversations that border on the repetitious.  Then, after taking a drink from a mug of freshly brewed coffee, she said, “You know, I’ve never understood it.  If mountains have been eroding all of these years, why isn’t the planet getting bigger with all of that eroded stuff?”

. . . a decidedly unlikely question from most mothers-in-law, but, in fact, not from my mother-in-law.  Still, I don’t think there was any lead-up to it.  Just . . . boom.  There it was.

I remember trying to describe the rock cycle with perhaps a touch of plate tectonics tossed in, but she wasn’t persuaded by my inarticulate exposition.  The idea of creation, destruction, and re-creation of rock gained no foothold, and it was my fault.

The memory of that conversation bubbled to the surface recently when I visited her in a retirement community in Hartford, Connecticut.  For nearly all of her adult life, she’s lived in the Hartford area, a landscape blessed with a dynamic geological history.  The turmoil of millions of years ago was certainly not the inspiration for her question, but that geological history relates wonderfully to what she asked.

The city of Hartford sits in the Hartford Basin (or Central Valley) on a swath of Triassic and Jurassic bedrock running from New Haven in the south, through Hartford, and continuing northward into Massachusetts.  This wedge, narrow at New Haven and expanding to the north, dominates the center of the state.


My understanding of what happened here depends primarily on geologist James W. Skehan’s Roadside Geology of Connecticut and Rhode Island (2008).  Errors of fact and interpretation are all mine.

(An aside:  Skehan is a very interesting figure.  This Harvard educated geologist and professor emeritus of Boston College is also a Jesuit priest who has written widely on the relationship between religion and science.  To give a bit of the flavor, in Modern Science and the Book of Genesis, published in 1986 by the National Science Teachers Association, he writes, “If we were to misrepresent the Bible as a scientific presentation, rather than as a theological document of Judeo-Christian religious history, we would do a great disservice to religion.”)

The Hartford Basin is the product of the unraveling of the supercontinent Pangea which began about 200 million years ago.  Some 50 million years earlier, the process of creating this single supercontinent had ended, a process that had launched mountain building over millions of years.  Now, as Pangea came apart along various fault lines, basins formed, including the North Atlantic Ocean Basin and the Hartford Basin, and as their thin crusts stretched and parted, magma flowed up to the surface.  In the Hartford Basin, ridges of basalt protrude from the basin floor, marking the remnants of the three principal lava flows that occurred here between 195 and 185 million years ago.  The most spectacular of the lot was the flow that created the Holyoke Basalt formation; its ridges dominate.  The rest of the floor is largely Jurassic sedimentary rock, material that eroded from the uplands to the east and west of the Hartford Basin.

In his general description of the interplay between the rock cycle and plate tectonics, Skehan describes succinctly the geologic process that played out here:
The forces inside the earth drive the rock cycle because compression builds mountains to be eroded and extension forms basins where sediments accumulate.  (Roadside Geology of Connecticut and Rhode Island, p. 5)
In the section from the 1985 bedrock geologic map of the state shown below, the wedge that is the Hartford Basin is prominent, a couple of very broad brush strokes of white and pale beige coloring.  Reddish fingers in the Basin are basalt bedrock.  (The map, published by the Connecticut Geological and Natural History Survey, is available from the U.S. Geological Survey’s National Geologic Map Database.)



The formation colored white (if labels were visible on the map above, this one would be “TRnh”), occupying a substantial portion of the southern portion of the wedge beginning on its western edge, is the New Haven Arkose from the Late Triassic.  The Early Jurassic Portland Arkose (pale beige, labeled “Jp”) and East Berlin Formation (darker tan, “Jeb”) make up much of the northern end.  This is all sedimentary rock, much of it sandstone and siltstone. 

(An aside:  Quarries in the Basin’s Portland Arkose formation produced the brown sandstone (which came to be called brownstone) used to construct many of the brownstones in New York City.  David B. Williams devotes a chapter to brownstone in his book Stories in Stone (2009), and he’s posted about it on his blog as well.)

The many substantial orangey-red finger-like extensions in the wedge, running roughly from the south toward the north-northeast, are Holyoke Basalt (“Jho”).  The fewer and narrower darker red strips are Talcott Basalt (“Jta”).  At places, they abut the Holyoke Basalt on the west; elsewhere, in the far west of the Basin, they stretch along its western boundary.  Both of these are from the Early Jurassic when Pangea was dismantling.

So appropriate that my mother-in-law’s retirement community sits on a ridge overlooking a portion of the Hartford Basin.  The ridge is called a mountain but hardly merits that designation.  The road to the top twists and turns, hugging a road cut exposing nearly vertical columns of rock, columns that, on occasion, must shed a chunk or two onto the asphalt.



According to the 1985 bedrock map of Connecticut, this exposed rock is Holyoke Basalt (orangey-red, "Jho").


The black arrow points to the approximate location of the retirement community on the basalt ridge.  Among the other prominent bedrock formations shown above are the Portland Arkose (pale beige, “Jp”), the East Berlin Formation (darker tan, “Jeb”), and the Hampden Basalt (light pink, "Jha"); all are from the Early Jurassic.

On my first visit to the retirement community, I took a walk along the road cut and collected a few pieces of rock.  The specimens are not particularly impressive and, in my geological ignorance, I have assumed they are all basalt, a tentative conclusion somewhat supported (well, not rejected) by a couple of colleagues who, at least, talk a good game of geology.  Here are two of the rocks.



I think much of what I saw in the road cut matches the specimen on the left.  In contrast, that on the right has a distinctive sheen, smooth to the touch, as well as some apparent layering.

Have I broached my mother-in-law’s old question with her after all these years?  No.  I doubt it’s of any interest and I suspect I would flub the explanation again.  Rather, I simply appreciate the whimsy of it all, having that exposure of Jurassic basalt outside her door.

Thursday, January 13, 2011

Sleep Tight . . . Evolution's At Work



Opening Comic Relief

Cul De Sac, the comic strip by Richard Thompson, features four-year old Alice Otterloop who tries to make sense of life.  In the strip that ran on January 9, 2011, her older brother Petey does what all older brothers do, they let younger siblings in on the secrets of the world.  In this case, it’s about the little, dirty trolls that live on the huge soot covered mountains of snow that, in the northeast, dominate shopping mall parking lots during the winter.  (The Otterloops live in the D.C. area; their last name is Thompson’s play on the “outer loop” of the Beltway, the highway that encircles the city.)

According to Petey, these trolls, or Sooti, capture and take “unwary bargain-hunting shoppers to their doom.”

Alice:  Really?

Petey:  That’s why you find abandoned shopping carts everywhere.

Alice:  Wow.  Nature is so cool.

(Alice’s exclamation got me, but, it’s not the final punch line.  Alice’s mom comes upon a cart and says, “Look!  Here’s a cart, and somebody’s left all their coupons in it!”)

Let the Horror Begin

Nature is so cool.  Sure is, though nature’s reality can be even stranger, and more unsettling and monstrous than Petey’s mythical Sooti.

This post explores a strange, unsettling monstrosity that nature has actually produced.  It’s a tale of evolution, striking with a vengeance.

Late last year, when I made plans to travel out of state and spend several nights in a hotel, I did all of the usual scouting on the web for room availability and good prices, but I also did what the seasoned and rational traveler now and for the foreseeable future will do, I consulted such web sites as the Bed Bug Registry to see if that wonderfully priced hotel room came with a dark secret (or a secret hiding in the dark).

Though in the U.S., awareness of bed bugs largely faded away in recent decades, there’s now the sickening realization that they’ve reentered our lives.  Just like Sheridan Whiteside in the 1930s Kaufman and Hart play The Man Who Came to Dinner, these creatures have come to stay, sleep in your bed, and quite possibly take over the house.  Whiteside’s terrorizing of his hosts was comic and benign, these creatures employ subtle and devastatingly effective methods of prolonged torture.  Think tiny vampires, only really, really scary ones.

The common bed bug is Cimex lectularius, the species of this family that has “most adapted to living with humans.”  (Michael F. Potter, Bed Bugs, University of Kentucky’s College of Agriculture.)  It is a member of the Family Cimicidae and, as a member of the Order Hemiptera, it is identified scientifically as a true bug.  Its scientific name is spot on.  According to the wonderful Dictionary of Word Roots and Combining Forms by Daniel J. Borror (1960),  the Latin roots for its scientific name are Cimex for “bug” and lectul for “couch” or “bed.”

For this post, I decided keep the threat level down and not include a photograph of one of the little beasts (they are under 1/4th inch in length as adults).  Instead, here’s a drawing of a female of the species; it appeared in the 1896 U.S. Department of Agriculture’s publication The Principal Household Insects of the United States (p. 32)  (Still rather creepy.)



I traveled a couple of weeks ago with two critical items in my suitcase – a copy of the Washington Post’s Urban Jungle column for December 14, 2010 (titled Abominable Holiday Hitchhikers - at this website, go to the #2 entry for December - you might also get a popup, the bed bugs of the web), and, from Cornell University’s New York State Integrated Pest Management Program, the handy wallet sized guide, Bed Bugs:  What Travelers Need to Know .  Both items are very useful and dispassionate about all of this, with steps to take when you travel.  There are other good resources on the web, including those prepared by the Centers for Disease Control and Prevention.  One of the best introductions to the scientific literature on C. lectularius is Biology of the Bed Bugs (Cimicidae) by Klaus Reinhardt and Michael T. Siva-Jothy, which appeared in the Annual Review of Entomology (2007).

As I explored C. lectularius, I kept returning to a question, “Why have bed bugs returned to prominence now?”  Several reasonable hypotheses have come from the scientific community; for irrationality, turn to the blogosphere which, in some areas, is awash with misguided political and economic thought about this issue.

Let’s start with the off base and oft repeated assertion that the widespread use of DDT had forced the damned bed bugs to their little arthropod knees and that the pesticide would have delivered the knockout punch then (or now) if only it hadn’t been banned in the U.S. in 1972.  Here’s just one example that ran in the Santa Clarita Valley (California) Signal on August 30, 2010:
Bedbugs, a common household pest for centuries, all but vanished in the 1940s and 1950s with the widespread use of DDT.  But DDT was banned in 1972 as too toxic to wildlife, especially birds.  Since then, the bugs have developed resistance to chemicals that replaced DDT.
Groups on the right use this kind of inaccurate conclusion in their general condemnation of government environmental regulation, blaming the ineffectiveness of current pesticides and the bed bug resurgence on the federal government and its intrusion into workings of the free-market (see Bedbugs Taking A Bite Out of New Yorkers from the libertarian Heartland Institute).

Such an argument conveniently ignores the decline in the use of DDT prior to the ban in 1972.  DDT was already no longer as effective as it had been because evolution was at work; insects, including bed bugs, had been developing resistance to the pesticide.  The director of government affairs for the National Pest Management Association has been quoted as saying, “Bloggers talk about bringing back DDT [to address the bed bug explosion], but we had stopped using it even before 1972.”  (Jerry Adler, The Politics of Bedbugs, Newsweek, September 8, 2010)

In fact, evolution is already implicated in the limited effectiveness of current pesticides, but in an interesting way.  According to the University of California’s Museum of Paleontology on its Understanding Evolution website, by virtue of natural selection, a few key genetic mutations that limited the effects of DDT spread had appeared in the bed bug population during the DDT tsunami.  Those mutations spread among the surviving bugs.  Apparently, even then, thanks to evolution, the bed bug was on the way back.

Although, with the DDT ban, those mutations were of less utility to the insect, they were nevertheless carried on from generation to generation.  Apparently, the pesticides that are the current “top choice” for dealing with bed bugs are pyrethrums; unfortunately, they work much the same way as DDT did – attacking the insects’ nerve cells.  So, the current batch of bed bugs comes prepared for our most popular chemical weapons.  Hardly the fault of government regulation, and, perhaps, in truth, the result of unregulated application of DDT in the 1940s through 1960s.

Further, the diminished bed bug population in the latter half of the 20th century cannot be attributed solely to the impact of DDT; other changes probably contributed as well.  Among those mentioned in the literature are improvements in personal hygiene, the impact of vacuum cleaners as they worked their suction magic, and regulation of the used furniture market.

So, what’s changed to cause the current plague?  Here are the some of the hypotheses put forward by scientists studying the issue.  In addition to the fact that C. lectularius has resistance to current pesticides, it has been suggested that the resurgence may be blamed, in part, on some combination of changes in tactics by the pest management industry (a broader use of baiting to control insect infestation, an approach that, unlike spraying, has little ancillary impact on bed bugs); a certain lack of attention to the issue by the hospitality industry; and increased international travel and commerce, particularly involving locations where bed bugs never took a real hit.  (See, for example, information posted by the University of Kentucky’s College of Agriculture and the Ohio State University Extension.)

Where did bed bugs come from in the first place?  According to the David Grimaldi and Michael Engel, entomologists and paleontologists with the American Museum of Natural History, although the superfamily Cimicoidea probably arose in the Late Jurassic, the Cimicidae are a product of the Eocene, concurrent with the appearance of bats on which the early version of Cimicidae members supped.  (Evolution of the Insects by David A. Grimaldi and Michael S. Engel, 2005, p. 329-330)  I came across speculation that C. lectularius may have evolved from that blood sucking bug that lived on bats.  When hominins started living in caves, perhaps some of these insects took advantage of the opportunity to enjoy a larger snacking area. (J.B.S. Haldane, The Causes of Evolution, originally published 1932, p. 5).

Cimicidae are of particular interest to evolutionary biologists for another reason, one that makes these vile creatures even worse.  The sex habits of the males of the entire bed bug family really pushes them to the top of the villain scale.  I wont go into any detail except to say that the male’s act is called “traumatic insemination” and the average life span of females is some 30 percent shorter than that of males, even though, in this sexual arms race, females have evolved to reduce the effect of this method of insemination.  More, if you want it, appears in the article I cited earlier, Biology of the Bed Bugs (Cimicidae) by Reinhardt and Siva-Jothy, or, to get right to the point, take a look at Costly Traumatic Insemination and a Female Counter-Adaption in Bed Bugs by Edward H. Murrow and Gören Arnqvist, Proceedings of the Royal Society B, September 10, 2003.

Closing Comic Relief

Lest you think that bed bugs are just another media-hyped frenzy, I know I am perfectly justified to be as obviously obsessed as I am because bed bugs have registered on the Dave Barry barometer of the real and profound.  Dave Barry's Year in Review: Why 2010 Made Us Sick has this entry for October, 2010:
On the legal front, the Supreme Court, as it does every October, begins a new term, which is hastily adjourned when the justices discover that their robes have bedbugs.
Okay, maybe the bugs aren’t really in the robes . . . yet.

Sunday, January 2, 2011

Temptations

First Voice:  I want it, I want it, I want it.
Second Voice:  You can’t have it.
         ~ Pete Townshend, Magic Bus

Against stupidity the very gods
Themselves contend in vain.
         ~ Friedrich Schiller, The Maid of Orleans


[Note:  Portions of this piece, including the title, were edited after the initial posting.]

Recently, a store in nearby Frederick, Maryland, lost a trilobite fossil to a shoplifter’s five-finger discount.  The 400 million year old fossil, which carried a price tag of $480, was apparently carefully lifted out of its display case and taken for a ride.  I was struck by the amount of press interest in this story, particularly when I didn’t think there was much to learn from it.  In contrast, there are fossil heists that have a thing or two to teach.  More on those in a moment.

In this instance, not unexpectedly the local town paper, the Frederick News Post, covered the story, but so did the Washington Post and the Associated Press, whose wire story was picked up widely.  United Press International carried it as well, though it managed to relocate the store to Virginia.  A local Maryland TV station covered the story on its website, complete with a picture of what may be fossils but certainly aren’t trilobites, much less the one that went missing.

Why would anyone care about this story beyond the very immediate area where folks might know the victimized store owner?  The value of the trilobite wasn’t huge, and the theft of a fossil from a store certainly doesn’t qualify as a man bites dog story.  The press didn’t appear to have been seduced by the opportunity to indulge in wordplay, though the AP did succumb a bit with this line:  “Police in Frederick are asking people to keep their eye peeled for a hot rock with a prehistoric degree.”  And the store owner couldn’t resist; he was quoted in the Washington Post as saying the trilobite “happened to walk away.”  Pretty mild stuff.

So, why the interest?  I don’t really have a clue, though I suspect this was a case of a self-respecting trilobite actually walking away in order to escape a store replete with crystals, hand crafted soaps, and “clever wood signs.”

Never Played with Country Joe and the Fish

Fossil thefts can be justifiably big news, particularly when the scientific and financial value of pilfered specimens is high, or the scale of the malfeasance is grand.  The theft of spectacular dinosaur fossils from federal and private land by Nate Murphy was one such recent story, covered internationally and in-depth.  Until the nasty truth came out, Murphy, an amateur paleontologist and commercial fossil collector, had widespread acclaim and star status for his scientifically and financially valuable (think in the hundreds of thousands of dollars) dinosaur finds.  He is a colorful character, considered almost larger than life, that is, until his house of cards fell in.  Apparently, one of his favored tools of the trade was deceit, particularly about where he was finding the fossils.

To me, among the most serious consequences of these crimes was the damage done to the relationship between professional and amateur paleontologists.  I guess when the financial variable is added to the paleontological equation, things can go out of balance.  Unfortunately, the reluctance of some professionals to welcome amateurs into the field is strengthened by Murphy’s exploits.

Not only were some of most renowned finds revealed to be thefts, but it turned out what he told of his background was often a tissue of lies.  Sadly, no, he never played with Country Joe and the Fish.  (Give me an F, give me an O, give me an S . . . .)

(Detailed background on the case appeared in 2009 in the Billings Gazette in a four-part series by reporter Ed Kemmick.  The series appeared on May 3, 4, 5, and 6, 2009.)

Artist and the Dinosaur Egg Fossil

The Otago Museum graces Dunedin, New Zealand (on the South Island).  Visited by some 300,000 people every year, this natural history museum offers exhibits exploring, among other topics, local Maori and Pacific cultures, animal life of the region, and the area’s paleontological history.  Were I to visit New Zealand (that is, when money becomes no object), the museum would be on my must-see list.  The highlight of the visit for me might well be the Animal Attic, housed in the Victorian Gallery on the top floor of the museum.  This is a faithful reproduction of a gallery and its display cases from the museum in the 1870s.  The gallery is organized around the Victorian era’s understanding of evolution, taking visitors from the simplest organisms to evolution’s crowning glory – human beings.

The museum’s top floor Victorian paean to the supposed pinnacle of creation was dramatically undercut one morning last year when, on the ground floor, an exemplar of this evolutionary process was busy stealing a fossil dinosaur egg from the museum’s gift shop.  Stupidity was at work.  This story generated lots of local coverage in New Zealand, with little beyond that, though it should have.

Unlike the trilobite disappearing from the Frederick, Maryland store, I think the Otago Museum dinosaur egg heist offers many levels of attractive complexity.

The story can be followed in the Otago Daily Times and it’s a fine one.  (The initial stories ran on August 5 and 6, 2010.)  It begins when museum gift shop staff discover that, shortly after the doors to the museum open for the morning, a dinosaur egg fossil has disappeared.  The egg, on sale for $1,700 in New Zealand dollars (a bit more than $1,300 U.S. dollars), was from a Hadrosaurus and laid sometime during the Cretaceous Period (146 to 65 million years ago).  Not a New Zealand fossil, rather something collected in China and purchased by the museum from a so-called “fossil supplier.”

The theft occurred on a Tuesday morning and, two days later, the egg was dropped off at the Dunedin central police station by a man who left the fossil in a shopping bag on an unstaffed counter.

Here’s one of the lovely wrinkles of this case – the ubiquity of security cameras and the obliviousness of the thief to them.  When he first struck at the museum gift shop, his every action was caught by security cameras.  Watching this footage (included in a 3News TV story) is akin to watching the grossly exaggerated movements of an actor in a movie from the silent film era.  Under the watchful eye of one camera, the thief looks around in a way sure to attract attention had anyone been around.  Then he suddenly reaches for the egg on the display and drops it into a bag.  He marches out of the museum, exposing a wonderful full face frontal view for yet another camera.  Two days later, after . . . what? remorse? strikes him, he slips into a police station with the egg in a plastic bag and hopes to do a stealth return.  Unfortunately, he doesn’t stop to think that police stations also might have security cameras and, once again, he makes no attempt to disguise himself (at least he could have worn a hoodie).  He leaves another very clear image for posterity.

Needless to say, it didn’t take long for the police to arrest a suspect, an artist from Invercargill (a town further south along the coast), and charge him with the crime (news story here).  Curiously, the fossil egg wasn’t the only ill-gotten gain he was arrested for; he also was charged with shoplifting some art books from a shop in another town.  Still, the outcome of all of this is a bit dissatisfying.  According to one report (the outcome is buried among the drug convictions), he was convicted of the art book shoplifting, but the charge of stealing the dinosaur egg, an act caught so plainly on video, was withdrawn.  Was there something more to the story, something that militated against prosecution, something that the media didn’t cover because it had moved on to more exciting things than the workings of the legal system?  I would love to know his motive.  Was it art related?

Perhaps it was having the cautionary tale of Nate Murphy in mind that it struck me as incongruous in the dinosaur egg case that the museum was in the business of selling fossils in the first place.  I think there may be some potential for conflict with their conservation and research missions when natural history museums engage in even this mild kind of open commerce in fossils.  (I know this smacks of blaming the victim.)  I understand that selling fossils in museum gift shops raises funds that support the museums’ missions and may nurture interest in paleontology.  Admittedly, these particular commercial transactions may be de minimis in the scheme of things.  Still, through their sale of fossils, are museums implicitly endorsing the treatment of fossils as primarily objects of commerce?  At a minimum, the Nate Murphy story shows there certainly are instances when fossils aren't appropriately bought and sold.  I would hope that museums take the sale of fossils in their gift shops as an opportunity to educate the buying public about provenance, legal collecting, and the like.  Perhaps they do.

Surprisingly, the local media did not fall prey to creative wordplay in covering this story.  Well, there were a few exceptions, such as this excerpt from one story:

Otago Museum staff are thrilled to have their fossilised dinosaur egg back, but would like to see the person who stole it caught.  Dunedin police yesterday were hatching a plan to do just that.

Or this headline:

Police crack case of stolen dinosaur egg.
 
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