Saturday, July 31, 2010

Venus, Mars, & Saturn

Three planets easily visible tonight in the western sky.  In you're in the Hudson Valley area, go outside tonight between 8:30 - 9:00 pm (when it gets dark enough to start seeing stars) and look due west.  The brightest "star" just above the horizon (hold your arm outstretched and make a fist - the "star" will be about one fist width above the horizon) is the planet Venus.

Facing west at 9:00 pm EDT.  See the triangle?

Just to the left a Venus, and a bit higher, are Saturn and Mars next to each other (Mars lower and with a reddish tint).  The three planets form a narrow triangle pointing down and to the right.

I'm teaching Observational Astronomy this fall if anyone's interested.

Is it just me?

I live near Rhinecliff, NY.  Not too near but close enough.  In case you haven't heard (like you're off camping with no TV, newspaper, or radio) Chelsea Clinton is getting married there today. 

Now I have nothing against Chelsea,  I even feel a bit sorry for her since she was often publicly picked on for her appearance when she was a teenager in the White House (imagine being a teenager and having people call you unattractive on national TV).  I hope her and her husband-to-be, Marc something or another, have a nice wedding (even though he's a hedge fund weasel and they're spending an truly obscene amount - several million dollars - on the grand extravaganza).

Anyway, the local, national, and international press has been crawling all over Rhinebeck, interviewing anyone and everyone walking down Main Street, and fawning over this "Wedding of the Century."  I've even heard the phrase "American Royalty" (how'd that work out for the Kennedy family, by the way?).

Give me a break.

Maybe it's just me, but I have a hard time understanding why anyone cares about this (or about Lindsay Lohan's legal problems or some clown named "Snookie" whose show I've never seen but see referenced everywhere).  Are people's lives that empty that they have to care so deeply about the lives of celebrities?  I can understand getting excited over a friend or relative's wedding, but why care about someone who'd like the Secret Service to shoot you if you got too close to hers?  Chelsea's famous because her father was president, not for anything she's ever accomplished.

Do people really want "American Royalty" or is it only the press?  Judging by the swooning in Rhinecliff, I do think some people want to worship the ground famous people walk on.  The whole concept of royalty - that people are better than you because of who their daddy is - seems morally reprehensible to me.  I'm afraid I could never meet people like the Queen of England (like there's a chance of that ever happening!).  While I'm happy to meet people, shake their hands, and make small talk, I'd never bow and scrape or call someone "your majesty."  That's why we picked up arms back in 1776!

So, have a nice wedding Chelsea but don't start thinking you're a royal princess even if some people would like you to play that role. Although given that you're spending more on this wedding than many Rhinecliff residents earn in their lifetime suggests that fame has already gone to your head.  Too bad.

Giant eurypterid trackway

Eurypterids are really neat animals which lived through much of the Paleozoic Era of geologic time (the Permian extinction event did them in like the trilobites).  The press likes to call them "sea scorpions" due to their appearance (they do both belong to the arthropod subphylum of chelicerata since they have pincers or fangs by their mouths called chelicerae).

There are over 20 known eurypterid families and some were formidable predators in the Paleozoic seas (one grew as long as 3 meters).  Here in New York, our state fossil is Eurypterus remipes - a Silurian Period eurypterid shown below.

Turns out an ancient eurypterid trackway was recently discovered in Scotland (northeast Fife).  The tracks were left on damp sand by a 2 meter monster called Hibbertopterus some 330 million years ago during the middle part of the Mississippian Period (Lower Carboniferous over there in Europe).  A BBC news article on the find states that "The track consists of three rows of crescent shaped footprints on each side of a central groove."  The animal was likely walking along a beach, dragging its tail (telson) to form the groove.

Fossil trackway on tilted sandstone bed (note hammer for scale)

Eurypterids may have had book lungs and could come out of the water occassionally, like horseshoe crabs (Limulus polyphemus) on Atlantic beaches today.  Would have been a neat site to see.  At the time, what we now know as the British Isles were near the equator and large areas were covered with equatorial swamps and riotous vegetation which later formed the coal deposits from which the Carboniferous Period derived its name.

The fossil trackway is along the coast in Scotland so it's in danger of weathering away.  They're creating a reproduction of it in silicone rubber so it can be studied.  It's a shame they can't save the actual slab.

Friday, July 30, 2010


In September of 1609, Henry Hudson and his crew sailed up the Hudson River and saw a very different landscape than that which we see today.  Sure the river's in pretty much the same place, the cliffs of the Palisades are still there, and we still have forests, meadows, and marshes adjoining the river but many other things would be unrecognizable to Henry Hudson today.  One of those is Manhattan Island.

Mannahatta: A Natural History of New York City (2009, Abrams) is a massive book by Dr. Eric Sanderson - an ecologist with the Wildlife Conservation Society at the Bronx Zoo. The word Manahatta comes from the Lenape Indians and means "island of many hills," an apt description of the area prior to settlement, an eventual alteration, of the area by Europeans.

Sanderson writes:

Mannahatta had more ecological communities per acre than Yellowstone, more native plant species per acre than Yosemite, and more birds than the Great Smokey Mountains National Park.  Mannahatta housed wolves, black bears, mountain lions, beavers, mink, and river otters; whales porpoises seals, and the occassional sea turtle visited its harbor.  Millions of birds of more than a hundred and fifty different species flew over the island annually on transcontinental migratory pathways; millions of fish - shad, herring, trout, sturgeon, and eel - swam past the island up the Hudson River and in its streams during annual rites of spring.
Quite a difference from the concrete jungle which exists today.

The book is great.  I especially liked the chapter on the Lenape - the original inhabitants of the island.  It's the type of book you can skim and just enjoy the pictures - especially the before and after images like that above - or delve into tremendous detail on Muir webs (ecological relationships between environments, flora, and fauna), geographic information systems (GIS), and details on the creation of the Mannahatta database.

Most libraries in the Hudson Valley should have this book although it's currently very reasonably priced ($26) on Amazon.  Highly recommended.

By the way, there's also a neat companion website at with an interactive map were you can see what any part of Manhattan looked like prior in 1609 along with interesting information for educators.


I realize this blog is called Hudson Valley Geologist and I've been posting a lot of biological stuff lately but that's what has been interesting to me as I'm out hiking.  On Thursday, I went with my family to a nature program for kids at Lake Minnewaska State Park and I learned a few new things as well on the nature hike (I never got to do cool stuff like that as a kid so I make up for it now as an adult by participating in the kid's programs!).

One of the things I learned was how to identify the witch-hazel (Hamamelis virginiana) tree.   Witch-hazel is a large shrub/small tree (3-8 m)  that prefers shady, moist areas with rich soil.  I spotted it on a north-facing slope.  According to Wikipedia, the genus name of Hamamelis supposedly means "together with fruit" since fruit, flowers, and leaf buds can be found on the plant at the same time.

The tree flowers in the fall, and the fact that there are still flowers on the tree in winter lead to witch-hazel to also being known as "winterbloom."  I didn't see any flowers on the tree since it's July, just fruit, but I'll keep my eyes open later in the fall since the flowers are an unusual yellow, spidery-looking bloom that should be easy to spot now that I know what to look for.

The fruit are green, slightly-fuzzy, acorn-looking objects.  They're dividing into two parts, each containing a black seed that is explosively ejected in the fall as far as 3-7 meters away from the tree.  I've read that Native Americans ate the oily seeds as a snack.

Witch-hazel fruits at Lake Minnewaska State Park 

From the U.S. Forest Service website, the leaves of witch-hazel are "...alternate, simple, broadly ovate, 2.5 – 6 inches long, unequal offset leaf base, with large wavy teeth on the margins and with the upper surface dark green and the lower surface a paler green."

Witch-hazel foliage at Lake Minnewaska State Park

Once I learned to identify the first one, I saw numerous witch-hazel trees on our hike - they're a lot more common that I had thought.

The plant is called witch-hazel because the leaves superficially resemble the hazel tree (Corylus americana) - source of hazelnuts - but they're not related.  The "witch" part of witch-hazel is thought to be derived from the Old English wice meaning "to bend" or "to manipulate" (same for the word "wicca" often used to describe witchcraft today).  The name comes from the fact that witch-hazel branches are pliable - used by Native Americans for bows - and traditionally used for "water witching" or dowsing.

The most common use of witch-hazel, however, is medicinal.  The chemicals in the twigs and leaves possess an astringent quality, shrink swelling in tissues and constrict blood vessels, with numerous external uses.  Witch-hazel is used on the skin for clearing up acne, stopping bleeding from razor cuts, soothing itchy insect bites or poison ivy, relieving the swelling of hemorrhoids, and shrinking bags under your eyes.

There are two traditional ways to make your own witch-hazel.  Mince the twigs and either soak them in alcohol (vodka works) for a couple of weeks to make a tincture or boil the minced twigs in water for a few hours to make a decoction (the method used by Native Americans).  You can also buy witch-hazel in the drugstore!

Look for this distinctive tree next time you're out hiking.

Wednesday, July 28, 2010

Horse Fly

Big nasty horse fly on my car the other day just after a thunderstorm.

I'm usually pretty tolerant of bugs but I don't like horse flies.  They'll buzz your head and harass you when you're hiking in the woods and their bites hurt like a bitch.  After a few miles of buzzing dive bombs from a determined horse fly, I've been known to snap, pick up a stick, and start swinging it through the air like a madman, and screaming death threats to an insect.

Females have long, sharp mandibles that rip and tear out a hunk of flesh for their blood meals (like mosquitoes, only the females need blood for nourishing their eggs).  Adult horse flies feed on nectar and therefore play a role in plant pollination.

Close-up is a bit fuzzy but you can see a couple of things.  The large compound eyes are separated rather than meeting on top of the head which indicates it's a female fly.  Also note the large mandible hanging down from its mouth, another female characteristic.

I like to classify plants and animals I take pictures of with their Latin (scientific) name.  Unfortunately, there are hundreds of horse fly species so the best I can do is that it's probably Tabanus sp. where "sp." is just an abbreviation for some species in the genus Tabanus.  It is, of course, a true fly (diptera) like the house flies it so closely resembles.

Even though I dislike these guys, and it will probably bite me next time I mow my lawn, I didn't kill it.  I just got it the car and drove down my driveway until it blew off.

Tuesday, July 27, 2010


Went hiking yesterday and saw this small sassafras tree on the Mohonk Preserve (they're pretty common).

Sassafras (Sassafras albidum) is easily recognized by its leaves - some are oval, some mitten shaped, and some have three lobes.  Here's a typical leaf:

Sassafras has long been used in traditional medicine was even a flavoring added to root beer before its use was banned (see below).  The roots can be diced and steeped to make tea which was used as a general tonic and was said to have diaphoretic and diuretic properties.  One traditional name for the sassafras tree was "ague tree" ("ague" refers to a fever with chills and sweating). 

The wood of sassafras was commonly used in the past for cabinets since the scent was thought to keep insect pests away.  The pleasant aroma of the tree was said to give healing and protection from evil influences in folk medicine.

A problem with sassafras is that it contains a chemical called safrole.  Safrole (C10H10O2 or 5-(2-propenyl)-1,3-benzodioxole) is considered by the Food and Drug Administration to be a weak carcinogen and hepatotoxin (damages the liver) and its use has been banned in foodstuffs.  This is based on studies in rats which were fed very large amounts of pure safrole.  Occasional use of sassafras tea is probably not going to cause you any harm (or at least no more so than much of what else we ingest on a daily basis - you'd be surpised by what "natural" foods we eat can cause cancer in large amounts).  Pregnant women should avoid it, however, since it does have abortifacient effects.

Anyway, here's a website listing things sassafras has medicinally been used for (and lots of dire warnings).

Interestingly, safrole is a one of the chemicals used in synthesizing MDMA (ecstasy) and is now a controlled substance (note - sassafras tea does not make you high!).

Monday, July 26, 2010

Stupid, stupid people

I’ve been to Yellowstone National Park with my family three times – most recently this June. One of the wildlife highlights are the bison just walking around and doing whatever it is bison do with their time. When entering the park, the rangers always hand out a little piece of paper warning against approaching the bison too closely – they may look placid like cows in a field, but they can move surprisingly fast and are sometimes foul-tempered.

By the way, even though the National Park Service calls them buffalo, that's a misnomer - they're only distantly related to African cape buffalo (Syncerus caffer) or the Asian water buffalo (Bubalus bubalis).  The American Bison (Bison bison) is a native North American beast with ancestors stretching back into the Ice Age.

Despite the warnings, numerous people are injured (some killed) each year by bison in Yellowstone. If you’ve ever been there, I’m sure you’ve seen people with cameras approach them far too closely given their sometimes unpredictable nature (and totally unnecessary too, since the advent of digital cameras with the zoom feature).

American Bison: A Natural History by Dale Lott (University of California Press, 2003) is an interesting book on bison I read a few years ago. In it, the author, a behavioral ecologist retired from UC Davis, recounts a couple of things he’s seen bison do including “tiptoeing” across cattle guards and jumping, from a complete standing-still position, up a six foot high embankment. It's a beast that can stand over 6 feet high, can weight upwards of 2,000 pounds, and run at speeds of 40 mph.  They're the largest living land animal in North America.

I love bison – they’re one of the most majestic sites of the western prairie. Tatanka, as the Lakota call them, once numbered in the tens of millions with thundering herds stretching for miles across the plains.

Bison herd at Wind Cave National Park, South Dakota

Today, there are only a few places where you can view small, managed herds – a sad remnant of a once mighty race of animals destroyed by human greed and stupidity (an estimated 50 million bison were killed in the 19th century).  The bison were on the verge of extinction by 1890.

Bison skulls waiting to be ground into fertilizer circa mid 1870s

Anyway, there was a video in the news this week about a bison charging and injuring a woman who was photographing it. She actually didn’t cause the bison to charge, however, some asshole just out of view of the video threw a piece of wood at it provoked the charge. Watch the video closely around the 26 second mark – see the wood bounce off the bison’s back? No wonder he was pissed.

Here’s the video.

What annoys me as well is the release by Yellowstone National Park officials which only says the following about the attack itself:

At about 8:30 p.m. on July 19, a 49-year-old woman and a 61-year-old male family member were exiting the Biscuit Basin thermal area to rejoin their family group in the parking lot, when a bison appeared in some nearby brush and charged them. The woman was struck and flipped in the air by the bison.
The video clearly shows the woman approached far to close to the bison - she admits to being closer than 30 feet and park regulations say you must be at least 25 yards (75 feet) away at minimum.  Why didn't they fine this idiot?  Second, why no mention of someone provoking the attack by throwing branches at the bison?  The park service makes it sound like an unprovoked attack.

Anyway, I never cease to be amazed at the depths of human stupidity and unthinking cruelty. I sincerely hope the park service didn’t do anything to this bison and it’s too bad the moron who threw the stick wasn't trampled to death to remove them from the gene pool (I like bison more than I like people who would throw sticks at them).

There's an interesting book called Death in Yellowstone: Accidents and Foolhardiness in the First National Park by Lee Whittlesey (Roberts Rinehart Publishers, 1995) if you're interested in reading about people who qualifed for a Darwin Award while vacationing in Yellowstone (here's a news flash - hot springs and boiling mud pots really are hot enough to cook you if you fall into one).

The water in this Yellowstone hot spring is boiling - not a place for a soak!

The Poisoner's Handbook

Checked out a book called The Poisoner's Handbook: Murder and the Birth of Forensic Medicine in Jazz Age New York by science journalist Deborah Blum (Penguin Press, 2010).  My wife did give me an odd look when she saw it in the pile of books I was checking out of the library.  When I saw the book in the library, I remembered that someone, somewhere had given it a good review (another science blog, likely).

The subtitle Murder and the Birth of Forensic Medicine in Jazz Age New York does give a better idea of what the book is about.  Blum discusses a number of chemicals which have poisoned people (intentionally and unintentionally) in New York City during the Jazz Age - the period of time between the end of World War I and the beginning of the Great Depression (primarily the 1920's).

The chemical poisons she covers in detail include chloroform (CHCl3), methyl alcohol (CH3OH), cyanides (HCN, KCN, NaCN), arsenic (As), mercury (Hg), carbon monoxide (CO), radium (Ra), ethyl alcohol (C2H5OH), and thallium (Tl).  Blum discusses famous poisoning cases detailing exactly how these poisons work and how forensic medicine developed as a science because of these crimes.

A biography of three early pioneers in forensic medicine is interwoven through the book as well - NY City medical examiner Charles Norris, his chemist associate Alexander Gettler, and NJ medical examiner Harrison Martland - and their constant battles for adequate funding and respect from the political powers of the era.  These men turned the medical examiner's office from a position filled by political hacks to well-respected, scientific institution.  The book is a bit gruesome at times, as Blum details how the medical examiners experimented on tissues extracted from dead bodies to work out  how to detect poisons in various tissues.  I wouldn't read it if vivid descriptions of how people die from arsenic, autopsies, and criminals frying in Sing Sing's 'old sparky' would disturb you.

There are a few errors in the book. 

She describes formic acid as the "essential part of the venom in bee stings" (pg 162).  This is an old idea about bee venom that's not true - only trace amounts are present and they're not an essential component (see O'Connor & Peck. 1980. Bee sting: The chemistry of an insect venom. Journal of Chemical Education 57(3):206).  The acid's name actually comes from the Latin word for ant, formica, and is present in ant stings.

On page 161, she writes "In 1923 German chemists had figured out how to make a synthetic methyl alcohol called methanol."  Methyl alcohol (although it wasn't called that at the time) was first isolated around 1661 by Robert Boyle (of Boyle's law fame) from the distillation of wood (hence the common name "wood alcohol").  In 1892, the International Conference on Chemical Nomenclature assigned the name methanol to methyl alcohol.  They're completely synonymous.

On page 73, she describes how Gettler "gave a dog 50 mg of cyanide (a little less than 2 ounces)." Um, 50 grams is a little less than 2 ounces, 50 mg is a little less than (2/1000) of an ounce.

Page 174 describes how "The executioner pulled the switch on the control panel, releasing a current of 2,000 volts through the wires..."  The units of current are amperes, not volts.

And this mess on page 184 after discussing the release of alpha particles by radium: "Radium also emits, to a lesser degree or positrons [sic], two other kinds of radiation: beta radiation, which consists of electrons, and gamma radiation, which contains a dangerous mixture of X-rays and other subatomic materials."  Gamma radiation is simply a form of electromagnetic radiation (with extremely short wavelengths), just like x-rays, UV, light, IR, and radio waves.

Page 178 states "European hot springs, famed for their healing powers, contained radon, a gas created by the interaction of radium and water."  No.  Radon-222 forms from the decay of radium-226 and is part of the decay chain of uranium-238 to lead-206.  See the full chain here.  It has nothing to do with water.

Errors like this are surprisingly common in many science books written by science journalists (most of whom were English or journalism majors in college and never had a lab science course).  I'm generalizing, of course, never having seen Blum's college transcripts, but the simple act of having an actual chemist read the book would have flagged those errors during the editorial process (why don't publishers do that - given what most of them are paid, many chemistry professors would happily accept a small check to proofread a book like this).

Anyway, I enjoyed reading the book and learned a few things.  I had always thought that deaths from drinking methyl alcohol (wood alcohol) during Prohibition were primarily those of desperate alcoholics who would drink anything.  Turns out, that much of the bootleg liquor at that time was highly poisonous and underground drinking was a game of Russian roulette.  Many middle-class New Yorkers poisoned themselves with bathtub gin and the medical examiners of the time actively lobbied for the repeal of Prohibition since they dealt daily with its consequences. 

The backstory on the development of forensic chemistry was interesting as well.  Modern CSI investigators owe a lot to their hardworking, underpaid, underappreciated forerunners whose curiosity and sense of justice moved them to do their wet chemistry experiments on the tissues of decomposing cadavers dragged in from the streets of New York.

Saturday, July 24, 2010

Heat index

The National Weather Service (NWS) issued a heat advisory for the mid-Hudson Valley today.  Temperatures in the mid-90's plus high humidity levels will give a heat index over 100 F.

The official NWS criteria for issuing a heat advisory is:

Issued within 12 hours of the onset of the following conditions: heat index of at least 105°F but less than 115°F for less than 3 hours per day, or nighttime lows above 80°F for 2 consecutive days.

A heat index is a measure of how hot it really feels given the air temperature and relative humidity.  We all know it feels hotter when it's humid out.  There's a physical reason for that and it has to do with water.

Water (H2O) can exist in three states at the normal range of Earth surface temperatures and pressures - solid ice, liquid water, and gaseous vapor.  When water changes state from ice to liquid to vapor, you have to add heat energy.  When water goes from gas to liquid to solid, heat energy is released.

When you get hot, your body responds by signaling sweat glands in your skin to perspire.  The liquid sweat on your skin will evaporate into the air and that change of phase from liquid to vapor requires heat energy - the heat of your skin.  In this way, the evaporating sweat essentially uses up heat energy off your skin and cools you down.

Now let's look at the air.  You can think of air as "holding" a certain amount  of water vapor (I know, I know, this isn't true at all but explaining it more correctly usually loses people and takes a lot more time - if you want to real story, click here).  The warmer the air, the more water vapor it can "hold."

Here's a graph illustrating this by showing the maximum amount of water vapor the air can "hold" (called saturation) at different temperatures...

The horizontal (x) axis is temperature in degrees Celsius (0 C = 32 F).  The vertical (y) axis is absolute humidty, that's how much water vapor is actually in the air.  The units are grams per cubic meter (g/m3).  Imagine an absolute humidity of 10 g/m3 - this means that a cube of air 1 meter on each side will only have 10 grams of water molecules floating around in it.

Looking at the graph, we see that at 0 C (32 F), the air can hold a maximum of 5 g/m3 of water vapor.  At 20 C (68 F), it jumps up to 20 g/m3, and at 40 C (104 F), it's up to 50 g/m3.  That's why we say that hotter air "holds" more water vapor (again, technically not really correct, but we don't want to get into vapor pressures and such).

From this, we can understand the concept of relative humidity (RH).  It's a percentage measure of how saturated the air is at that temperature.  For example, 0% RH means there's absolutely no water vapor in the air (never happens) and 100% RH means the air is saturated for that temperature (frequently happens - whenever it's raining out, the RH is typically 100%).  We said in the previous paragraph that at 20 C, the air can "hold" 20 g/m3 of water vapor.  Suppose it's 20 C, and we measure the amount of water vapor in the air as 10 g/m3.  What's the RH?

     RH = [(amount of water vapor in the air) / (what the air can "hold" at that temp)] x 100%
     RH = [(10 g/m3) / (20 g/m3)] x 100% = 0.5 x 100% = 50%

The relative humidity is 50% because the air is half saturated (it has 10 g/m3 of water vapor and can "hold" 20 g/m3 at that temperature).

The higher the relative humidity, the longer it will take sweat to evaporate off your skin.  When the air is dry, it evaporates quickly.  If you've ever been to an arid climate, you'll have experienced this.  Just last month, I was in Moab, Utah hiking in Arches and Canyonlands.

Air temperature was over 100 F.  I drank several liters of water but my skin was dry and, while the sun was strong, I felt relatively comfortable.  Today, if I did a hike here in NY, I'd be drenched and dripping with sweat.  The difference?  In Utah, the very low RH allows sweat to evaporate almost instantaneously while here in NY the higher RH means it evaporates more slowly or not at all.  The evaporating sweat cools you so 100 F in Utah is often more comfortable than 90 F in NY.

That's where the heat index comes in.  Here's a chart from the NWS.

Right now, at my house, the air temperature is around 90 F and the RH is 60%.  This gives a heat index of 100 F.  Meaning if you are outside, it feels like 100 degrees (and it's not even the hottest part of the day yet).  If the air temperature goes up a few degrees, the heat idex can significantly increase.  It's not just the temperature that makes you feel it, however, it's also the fact that you'll be sopping wet with perspiration.

If you want something a bit more exact, the NWS has a heat index calculator online where you enter the temperature and RH (easily obtained for your hometown from the NWS website) and get the heat index.  How is the heat index calculated?  It was worked out in the 1970s by a researcher named Robert Steadman who made a bunch of assumptions on things like body mass, height, type of clothing, amount of physical activity, sunlight exposure, wind speed, among other factors.  It's an approximation - if the wind is blowing, or you're taller than average, or you're jogging in the full sun, how hot you feel can be significantly different from the heat index.

The formula is actually quite complex (HI is the heat index, T is the degree F temperature, and R is the relative humidity)...

HI = [(-42.379)] + [(2.04901523) * T] + [(10.14333127) * R] - [(0.22475541) * T * R] -
        [(6.83783x10^-3) * T^2]  - [(5.481717x10^-2) * R^2] + [(1.22874x10^-3) * T^2 * R] +
        [(8.5282x10^-4) * T * R^2] - [(1.99x10^-6) * T^2 * R^2]

As some of you will recognize, this is an approximation formula, as you add more terms you get more decimal point accuracy.

However you calculate it, it's damn hot today in the Hudson Valley and I'm glad to have air conditioning!

Friday, July 23, 2010

Damn faculty, standing in the way of student success...

One of the blogs I read is Confessions of a Community College Dean.  I teach at a community college, am currently a department chair and did a one-semester stint as an Acting Associate Dean of Academic Affairs, so much of what he blogs about is very familiar.  I usually like what "Dean Dad" (as he calls himself) has to say.

I do have some issues with his last post, however, where he talks about calculators in math classes.  After an introduction, which I'll return to in a minute, he writes...

That said, it’s pretty clear at my college -- and at many, many others -- that lower-level math classes (especially developmental) are the most difficult academic obstacles many of our students face. The drop/fail rate in developmental math is embarrassingly and stubbornly high, and the national literature suggests that students who drop out because they feel overmatched in math are among the least likely ever to return.
Same at our institution and everyplace else given discussions I've had with my colleagues at other institutions.  It truly amazes me that students earn a high school diploma in June, enter our college in August, and the mandatory math placement exam puts them into remedial math (the equivalent of 8th grade, or lower).

Many of these students also place into remedial English, being unable to write a coherent sentence,but that's another story.  Our local high schools are failing society by allowing illiterate students to graduate with diplomas (and New York consistently ranks among the top 5 states in spending per student - we're wasting our money).

Well  "Dean Dad" was complaining in his blog that professors at his school didn't allow students to use calculators in their math classes.  He admits to some sympathy for this, citing the need for students to have an ability to distinguish reasonable from unreasonable answers.

Another short digression...  I teach geology and I've seen first-hand that students often have no number sense.  This usually shows up in my map lab where students learn to work with topographic (and other) maps.  I've seen students use calculators to convert a number in kilometers to meters (for those in the humanities reading this, it's simply a matter of moving the decimal place to the right 3 places - a distance of 1.2 km is simple 1,200 meters - hardly a matter for the calculator).  I've seen students multiply instead of divide when doing map scale conversions and then write down that it's 15,400,000 kilometers between two towns on the map instead of the correct answer of 15.4 km.  These problems are the sole result of students using calculators from their earliest math classes and failing to develop a sense of what constitutes a reasonable answer.

"Dean Dad" then assumes a correlation between not allowing calculators in the classroom and student's poor performance in college math classes.

...but is it worth flunking out huge cohorts of students because their high schools let them use calculators and we don’t?

He then writes:

At this point, the local high schools seem largely to have moved into the calculator camp. Wise and worldly readers, should we follow?

Here's the problem.  At my institution, we do more than allow calculators in math classes, we force the students to purchase fancy TI programmable calculators for the college algebra sequence (the equivalent of 9th grade algebra back when I went to school, by the way).  We still have the same problems with student retention as those at "Dean Dad's" institution.  It's not the calculators!

Let me just add a few more thoughts as well...

"Dean Dad" seems like a nice guy and I typically agree with him, but he started hit blog post by writing:

My scholarly background is in a social science discipline, not math. I have no particular pet theory on the right and proper way to teach math.

This is why we need to preserve tenure (which "Dean Dad" also dislikes).  What professors like me fear, is that a dean will then decide that math professors will need to change their calculator policies and the way they teach their classes because the dean thinks it will help retention (with no basis for believing this other than random anecdotes).  Or in geology, my field, that a dean, college president, or trustee will decide that I am not being fair by teaching about how fossils support biological evolution and not intelligent design (or, even worse, young-earth creationism and Noah's flood).  "Dean Dad", with no particular academic background in math, does not trust that his colleagues with PhDs in math are teaching it correctly.  It's perfectly acceptable for "Dean Dad" to have discussions with his math faculty about student retention and remedial math education, it's definitely not his place to try and get them to sacrifice academic standards to get there (which is how the math professors are going to view such interference).

Another point.  Math isn't arithmetic.  High school math is basically the minimum you need to know to get by in society (I wish they'd teach more statistics so people were able to think more critically about them when they're quoted in the media or advertising).  College mathematics is an academic subject - not job or life-skills training.  You do need to know the rules of arithmetic to understand mathematics, just as you need to know the alphabet and how to spell words before you can write essays, but much of math is symbolic, not numeric.  College-level math and science professors want to get students away from "What's the formula so I can plug in numbers and get a numeric answer on my calculator?" to understanding the problem and deriving a generic formula to obtain the information you need (without even using numbers).

I like what Chad Orzel wrote about "Dean Dad's" post over at his Uncertain Principles blog...

I think it's reasonably accurate to say that the notion that math at the college level involves calculators is rather like the belief that history at the college level is about memorizing the names of the kings of England, or that English at the college level is about parts of speech and metrical forms, or that economics at the college level is about learning to balance your checkbook.

At some point, overreliance on a calculator becomes a hinderance in the learning and understanding of math and science.  I think "Dean Dad" is dreaming if he thinks allowing calculators in math classes will increase student retention at his institution.  He just needs to look around at other institutions, like our NYS community college which allows calculators, to see that our retention of math students is just as bad.

I think I do know the reason for the retention problem but no one likes talking about it.  As a community college, we're an open door institution - pay the money and come on in.  I think that's one of the greatest things about our country - everyone has a chance to succeed and get an education.  The problem, however, is that not everyone has the ability or is motivated enough, for whatever reason, to earn a college diploma.  The administrators want to increase enrollment and retention while tenured faculty members like me want to uphold academic standards - even if it means people will flunk out and never return.  This is another reason to support tenure, by the way, without academic standards, college diplomas become truly worthless.  Those two goals are sometimes mutually exclusive.

Thursday, July 22, 2010

Opus 40

The Town of Saugerties library sponsored a free evening at Opus 40 last night so I went with my family.

If you haven't been there, it's an incredible bluestone "sculpture" covering 6 acres of an old bluestone quarry and the vision of a single man - Harvey Fite (1903-1976).  Fite got a job teaching art at Bard College and purchased 13 acres around the present site, with beautiful views of nearby Overlook Mountain, for $250 (!) in 1938.  He built a house overlooking the quarry and started creating this environmental scuplture (without, at first, realizing its eventual complexity).  Later he named it Opus 40 since he planned on spending 40 years to complete it.  He almost made it, dying 3 years shy of his goal when he accidently drove his lawn tractor off a wall into the quarry.

Fite was inspired by Mayan stonework, done completely without mortar, and built most of the structure single-handedly with typical 19th century quarryman tools.  You have to walk around the site to appreciate what an amazing achievement this was - and you start to realize it probably wasn't that difficult to build many of the ancient monuments around the world.  If one man can build Opus 40 in 37 years, Mayan laborers could certainly have built their ancient cities in a couple of decades.

Negotiations are on-going for the Town of Saugerties to acquire the site since the stepson of Fite, Thad Richards, who has been operating the site as a non-profit, is now of retirement age and planning for its future preservation.  Here are some pictures...

As you approach the monument

The monument (thunderstorms were rolling through the area)

Beautiful stonework

Stonework abutting natural quarry wall
It's impossible to get it all in one photo

Here's a great aerial photo of the entire site.

There's some interesting geology visible there too if you know what to look for...

Beautiful glacial striations & polishing on top of the quarry

An ancient stream channel fossilized in the quarry wall

Woody plant fossil material in one of the bluestone pavers

I'll write more about Catskill bluestone at some point.

Monday, July 19, 2010

Nature image - Libellula

Hard to photograph these guys...

Widow Skimmer - Libellula luctuosa

Taken in my backyard.  Skimmers belong to family Libellulidae, the largest dragonfly family in the world with over 1,000 species.  Dragonflies have compound eyes with tens of thousands of facets giving them a nearly 360 degree view and excellent movement-sensing ability - apropos for aerial hunters of other insects.  They are, however, completely harmless to humans neither biting nor stinging.

The fossil record for dragonflies goes back some 300 million years (Carboniferous Period) which was almost 100 million years before the appearance of the dinosaurs.  Some of these ancient animals had wingspans of 70 cm (over two feet)!  Here's a beautiful dragonfly fossil (Meganeura) from the Carboniferous.

They haven't changed much since then (obviously an effective body design and mode of life).

Sunday, July 18, 2010

PNG earthquakes

Couple of big earthquakes today in Papua New Guinea (PNG) and numerous aftershocks.

A magnitude 6.9 at 1304 UTC  and a magnitude 7.3 a half-hour later at 1335 UTC (9:00-9:30 am EDT).  The depth of the two quakes ranged from 42-58 km (25-35 miles down).  The map below shows the epicenters on New Britain Island by blue boxes.

The red line represents a sea floor trench south of New Britain - the surface expression of a major fault which dips northward below the island.

This area of the world is a complex amalgamation of tectonic microplates.

The Solomon Sea microplate is moving northwards and sliding down beneath the South Bismarck Plate forming a seafloor trench.

As the plate subducts, it melts providing magma for active volcanoes on New Britain Island.  It also moves by stick-slip behavior.  It sticks, stresses build up as the plate is pulled on by the subducting slab, and then it slips somewhere along its length.  Bang - an earthquake.

Nothing unusual for this part of the world.

Technologically illiterate students...

Interesting article in Inside Higher Ed on Technologically Illiterate Students.

At my institution, all of us "old" professors keep getting told that we're digital immigrants while our students are digital natives. In other words, they grew up with digital technology like computers while us older folk came to it later in life. What typically follows is the idea that we then have to modify our teaching to reach these Generation Z students - maybe by incorporating "cool" things like Second Life, Twitter, and podcasts.
There is some truth to this digital native business in that my kids were using our computer since they could move the mouse and I never used one until I entered college. We have to remember, however, that my generation invented the fucking Internet to begin with and some of us "older" computer users learned numerous programming languages (Basic, Pascal, Fortran, C) and used computers that required MS-DOS commands or, better yet, UNIX commands (biff, grep, ls, emacs).  I may have started using computers later in life, but I think I'm more knowledgable about how they actually work than many of the so-called digital natives!
Anyway, speaking for myself, I view these various technologies (Second Life, Twitter, etc.) as tools and just as I wouldn't hammer a nail with my carpenter's level, I don't feel the need to Twitter things to my geology students.  It simply doesn't fit in with how I approach the material, the class, and my students.  It's true I blog, but this isn't for my students (even if they stumble upon this and read it), it's for me.
I suppose I could create some Second Life world where my students meet and examine some imaginary rock outcroup and learn how to take strike & dip measurements with a compass.  Then again, I could just drive them in the college van to a real rock outcrop, hand them a damn compass, and have them do it in real life with me looking over their shoulder.  Which do you think would be a more effective teaching method?

The problem I have with students in my classes is not that they don't know how to use technology in general - for the most part they do.  It's that they don't know how to use technology effectively in a learning environment.   They can snap pics of their drunk friends with their cell phone and upload them into Facebook but they can't take collected data points, put them into Excel, and plot a best-fit line.  They can look up information online but don't have the sense to understand why gathering information from a Wikipedia article is unacceptable as their source (sole source!) for a research paper in a college-level science class.
A final thought, learning something takes effort.  No one likes to admit that, but it's true.  Just as you need to work out to develop muscles or lose weight, you need to read, study, and ponder the material to learn it.  It really doesn't matter if the material is delivered through a book, traditional lecture, podcast, blog, or hundreds of tweets.  There's effort required on the part of the student receiving the information.

Saturday, July 17, 2010

Observational Astronomy

Since I am publicizing my fall semester Ancient Astronomy (AST-105-S01) course, I might as well publicize another which could use higher enrollment as well - Observational Astronomy (AST-103-B51).

This is a blended course, meaning there is an online component, as well as meeting face-to-face on Thursday evenings, 7:00 - 10:00 pm from September 9 - November 4 on the Ulster County Community College campus in Stone Ridge.  Here's the official course description:

This night course is a hands-on introduction to observing the night sky, how to locate these objects using celestial coordinate systems, and how to utilize the Internet and computer programs to obtain astronomical information. Most of the laboratory time will be spent outdoors learning the names and locations of stars and constellations and utilizing the department's telescopes to observe and study the moon, planets, deep sky objects, and other astronomical objects which might be visible. The course will include observing trips during class time to local areas away from the light pollution on campus.
It's not an academic astronomy course (we have AST-101 Astronomy of Stars & Galaxies for that).  You will learn what Messier objects are, how a planetary nebula forms, etc., but it's primarily a hands-on course teaching you how to look at the night sky and how to use a telescope.  We don't have a planetarium on campus although I do arrange to go visit one during the course time.

The online component of the course will teach you how to use the Internet to obtain astronomical information, how to download a free planetarium program allowing you to see what's up in the night sky for any night and/or location on Earth, and how to select objects to view in the night sky.

One of the scopes you'll learn to use!

The face-to-face component of the course will introduce you to the constellations and how to find your way around the sky and then allow you to use a telescope (we start with 6" Dobsonian reflectors but have other scopes available).  We'll be observing the satellites (naked eye), the Moon, whatever planets are out, and various celestial objects like Andromeda, the Ring Nebula, Albireo, Hercules Cluster, and others.

I always have great feedback from students who take this course telling me they had a great time and learned a lot.  If you want to know more, feel free to contact me.

Wednesday, July 14, 2010

Ancient Astronomy Course (repost)

I'm excited about a new course I'll be teaching next fall but enrollment's still a bit low so I thought I'd advertise it again.  It's a fully online course on Ancient Astronomy.  Here's the description...

This online course will examine the earliest origins of astronomy, our oldest science. The first half of the course will introduce students to the night sky. Topics covered will include the movements of the Earth and other solar system objects; the phases and cycles of the Moon; the origin of seasons, solstices, equinoxes, and eclipses; constellations and celestial navigation; and how ancient astronomers used their observations in developing civilization’s earliest calendars.

The second half of the course will be a broad survey of the historical development of astronomy from ancient times up to the scientific revolution of the Renaissance Period. Cosmologies from representative cultures around the world will be examined along with significant archaeoastronomy sites including the Egyptian pyramids, Stonehenge, Newgrange, Chichen Itza, Machu Picchu, Chaco Canyon, the Big Horn Medicine Wheel, and others.

This course is followed by an optional January 2011 fieldtrip to the Yucatan area of Mexico to further study Maya archaeoastronomy.

No prerequisites and it's on the SUNY Learning Network (SLN) even though it's offered through SUNY Ulster County Community College.  That means you can take it even if you're a student somewhere else (it's online, you can take it from anywhere in the world!).

If you're interested in learning more, feel free to contact me and if you're interested in registering/costs/etc., contact the SUNY Ulster Registrar's Office at 845-687-5075 or 1-800-724-0833.

Nature Image - Thamnophis

Thamnophis sauritus - Eastern Ribbon Snake
Thamnophis sirtalis- Eastern Garter Snake

Why two identifications?  I am not really sure which it is.

These snakes are very common in my neck of the woods (the picture was taken in a firewood pile next door to where I live in the mid-Hudson Valley of New York). Despite the threatening position, they're completely harmless (I even owned a captured one as a pet for a summer when I was a kid - my mother made me keep the aquarium outside!).  They swim well and I've often seen them eating small frogs although they'll eat just about anything they can swallow whole.  This one probably ate recently as witnessed by the slight bulge a couple of inches below its head.

According to Nearctica, the identifying characteristics of ribbon snakes are:

Snake 18 to 40 inches in length. Tail elongate and slender, comprising nearly one-third of the length of the snake. No fused dark spots present on the crown of the head. Body with a light yellow to white dorsal stripe and a yellow to white lateral stripe on both sides of the body. Lateral stripe located on the 3rd and 4th scale rows. Underside of head and belly white. Belly with a dark brown stripe along each of the outer margins. Dorsal body scales keeled and anal plate single.

I think it's a ribbon snake (although I didn't examine for a single anal plate!) but not 100% sure.  Here's another seen while hiking at the Mohonk Preserve in the Shawangunks in the fall.

Harder to tell.  Here's the eastern garter snake description from Nearctica:

Characters in common include usually the presence of a dorsal and lateral stripes. Lateral stripes are located on the 2nd and 3rd scale rows. Head usually with 7 labial scales. Dorsal scales keeled and anal plate single...  Midline and lateral lines usually yellow; lateral area between midline and lateral line usually gray-brown with a double row of alternating; coloration, however, individually variable.

Clearly they're both Thamnophis sp. but I can't really identify them with more certainty - I'd need to examine two snakes, one from each species, at the same time, I'm thinking, to be able to really tell them apart.  I'm guessing one of the more distinctive features would be that the lateral stripes in ribbon snakes are 3rd & 4th scale rows while on the garter snake they're on the 2nd & 3rd scale rows.  Problem is, when I look at the coiled guy, I think I see something like five rows of alternating scales between the midline and the lateral line!  The description for the garter snake does say there's a "double row of alternating" (alternating what?) between the midline and lateral lines.  There is an double alternating pattern of darker dots on both (fainter on the coiled guy, but it's there).  Maybe they're both garter snakes then.

Can anyone give helpful suggestions on how to tell them apart next time I see them?  I think I will grab one and look at it more closely.

Tuesday, July 13, 2010

Manhattan garnet

One of the most impressive mineral specimens unearthed in New York City is the famous Kunz garnet (also called the sewer garnet or the subway garnet) discovered in 1885.  It's a massive 9 pound, 10 ounce almandine garnet, seven inches in diameter, dug up on West 35th Street near Broadway. 

Today the area looks like this:

Not a great site for mineral collecting anymore!

There are a number of conflicting stories about this garnet.  Different sources state that it was uncovered during the excavation of a sewer or a subway.  The oldest source, however, related by mineral collector and dealer John Betts, shows that it was apparently a sewer excavation.

From the 1886 New York Academy of Sciences Transactions (Vol. 5, pp. 264-266):

The finest large garnet crystal ever found, perhaps, in the United States, was discovered, strange though it may seem, in the midst of the solidly-built portion of New York City. It was brought to light by a laborer excavating for a sewer in West 35th Street, between Broadway and Seventh Avenue, in August, 1885. A quartzite vein, traversing the gneiss, contained the crystal.

The garnet eventually found its way into the hands of George F. Kunz (1856-1932), an emminant New York City mineralogist who described it to the New York Academy of Sciences (hence the name Kunz garnet).

Various sources state that this garnet was, for a time, used as a doorstop for the Department of Public Works in New York City but I've been unable to verify this anywhere. A good story if it's true!

Anyway, Kunz presented the garnet to the New York Mineralogical Club which later donated it to the American Museum of Natural History in Manhattan.  I believe it's on display in the New York City Minerals collection but I haven't been there in a few years.

Hundreds of spectacular mineral specimens have been discovered in the bedrock of Manhattan (primarily in the 19th century when a lot of the subway, skyscraper, and water tunnel excavations were going on).  The Kunz garnet was found in the Manhattan Formation (also called the Manhattan Schist), a rock unit which underlies much of the island and formed from the metamorphism of sedimentary rocks by a mountain-building event some 440 million years ago (Taconic Orogeny).

I'll write more about the Manhattan Formation another day.

Monday, July 12, 2010

Oldest multicellular life?

Life on Earth arose over 3.5 billion years ago.  This early life was bacterial - single-celled without a nucleus (biologists call them prokaryotes).  The earliest were believed to belong to a group called archaea - sometimes known as extremophiles because they can live, and thrive, in extreme environments on Earth today (like those that provide color to the Yellowstone hot spring below).

Eventually, these single-celled organisms learned to group together and cooperate as multicellular animals - the metazoans.  Metazoans became abundant around 600 million years ago with the development of a group of organisms collectively called the Vendian Fauna.  Fossils of these animals are found throughout the world - most famously in the Ediacara Hills of Australia.  Many of these fossils represent organisms similar to those today (like jellyfish) while others represent extinct lineages completely different from anything living in today's oceans.

What we usually teach when discussing the origin and evolution of metazoans in geology class is that single-celled eukaryotes (organisms with a nucleus) like choanoplagellates learned how to clump together and chemically communicate to form sponges - thought to be one of the earliest multicellular organisms.

Sponge classification and their relationship to the rest of the metazoa is problematic (they're not monophyletic for you biology types) but we'll ignore that for now.  Problem is that all of the earliest metazoans were soft, squishy things (hard parts hadn't been "invented" yet) and these types of organisms simply don't fossilize well.

There are other, older, weird fossils which have been discovered which may or may not be multicellular.  An example is the 2 billion year old Grypania spiralis - possibly a eukaryotic, multicellular, algae.

Most recently, a group of researchers announced in Nature the discovery of 2.1 billion-year-old fossils from sedimentary rocks in Gabon, West Africa that may be metazoans.  They've collected over 250 specimens which range in size from 1-12 cm.  An example of the detailed x-ray imaging they're doing on these samples is shown below.

The team argues that the complex shape and folding is indicative of more than just a group of colonial prokaryotes, that it indicates chemical signaling - a characteristic of multicellular life.  Carbon and sulfur isotopic analysis of the fossils indicates that they are indeed fossils and not simply mineral formations (the soft tissues have been replaced by the mineral pyrite - FeS2 - a common mode of fossilization).  Since all the soft tissues are gone, it's a challenge to figure out exactly what these were.

Analysis of the sedimentary rock indicates these organisms - whatever they were - lived in oxygenated sediments some 30-40 meters below the surface of the ocean.

The challenge of talking about the origin of multicellular life is that the fossils are so few and far between and ones we do have provide only limited information.  One thing all discoveries indicate, however, is that the story of life on Earth is long, complex, and interesting.