30 May 2008

Trike repair - Episode 2

The seat of the Greenspeed Anura attach to the main frame with 2 allen screws underneath (picture below) and a couple more all the way in the back. This arrangement makes it easy to remove and reattach the seat. But at the same time, the seat is not entirely stable.

Soon after I started riding mine, the screws underneath the seat started getting loose, making the seat wobbly. I would tighten them before each ride, but within about a half an hour, they would be loose again. I do most of my riding on bumpy trails with many twists and turns. As you can imagine, that creates a whole lotta shakin' and shiftin' that undoubtedly contribute to the loosening of screws. But still, the seat itself shouldn't get loose so easily. Do I dare claim there is a design failure here?

TrikeSeatScrews1

So, a week ago I e-mailed Paul Sims, the "Production, Tech, R&D and Web Guy" at Greenspeed Trikes all the way down under in Australia. He responded as quickly as the time difference between Maryland and Melbourne allowed and has since been very helpful. Paul suggested that I replace the allen screws with ones with bigger heads and put some thread locking glue on them.

TrikeSeatScrews2

I followed Paul's advice and replaced the 2 screws underneath the seat. Before screwing them in, I also put a liberal amount of Loctite Thread Locker on each. Loctite comes in removable and permanent varieties, the latter requiring application of heat to break the cured glue should it ever become necessary to remove the screw. For starters, I decided to use the removable kind.

Since then, following two 45-min rides on the same bumpy trails, the screws have remained tight. If they start to loosen again, I may switch to permanent Loctite. I was also going to replace the screws in the rear that connect the tubes coming down from the back of the seat to the frame, which are narrower and longer, but couldn't find anything comparable in Home Depot. The original ones are so far holding on with a little help from Loctite.

Trike repair - Episode 1


29 May 2008

Is it an isopteran? Is it a zorapteran? It's a psocopteran!

psocopteran1

I noticed these itsy bitsy teenie weenie insects, barely a millimeter long, running around on some pieces of wood I had in my garage last weekend. I photographed them and then went over to my wife to make the grim announcement: "I think we have termites in the garage."

Later, however, having done some reading on termites (isopterans), I decided that they were too small to be termites. Besides, the wood they were seemingly inhabiting was not rotten or otherwise damaged in any visible way.

They remained nameless until yesterday afternoon when I saw a picture of a zorapteran whilst reading Christopher Taylor’s “completely-biased” list of phylogenetically problematic taxa. I immediately said to myself: “That’s it! Those insects in the garage are zorapterans.” I posted a couple of their pictures on BugGuide.net, calling them zorapterans but with a question mark.

Less than a half an hour later, it turned out that I was wrong once again; the creatures from the garage were instead identified as psocopterans (also called psocids, booklice or barklice).

psocopteran2

From Borror & DeLong (An Introduction to the Study of Insects, 3rd. ed., 1971):
Psocids feed on molds, fungi, cereals, pollen, fragments of dead insects, and similar materials. The term "lice" in the names of "booklice" and "barklice" is somewhat misleading, for none of these insects is parasitic, and relatively few are louselike in appearance. The species occurring in buildings rarely cause much damage, but are frequently a nuisance.
And according to this page:
Booklice are more common in human dwellings and warehouses... Most species feed on stored grains, book bindings, wallpaper paste, fabric sizing, and other starchy products.
No need to call the exterminator, then. But I will try to get better pictures of them over the weekend.

Note added 28 February 2009: A few days ago the creature got a more definite identification: Liposcelis bostrychophila. See BugGuide.net.

27 May 2008

Creature from brown slime

DragonflyNymph1

If I am not mistaken this is a dragonfly nymph. I photographed it at Hoyles Mill Park last Saturday. It was in the creek clinging to the side of a rock with its posterior end in the water.

DragonflyNymph2

Were the immediate ancestors of insects aquatic or terrestrial? The most commonly accepted answer seems to be that insects descended from terrestrial ancestors that themselves had evolved from marine ancestors. But when one considers the groups like the order Odonata (dragonflies and damselflies), where the majority of the species have aquatic juveniles, one may tend to think that this is an evidence in support of the opposite route of insect evolution: from the sea to land via estuaries and freshwaters. Gullan & Cranston (2005), however, offer one counter argument:
Another line of evidence against an aquatic origin for the earliest insects is the difficulty in envisaging how a tracheal system could have evolved in water. In an aerial environment, simple invagination of external respiratory surfaces and subsequent internal elaboration could have given rise to a tracheal system...that later served as a preadaptation for tracheal gas exchange in the gills of aquatic insects.


Gullan, P.J & Cranston, P.S. (2005). The Insects. 3rd ed. Blackwell.


Grayscale beech

B&Wbeech

I found empty Anguispira fergusoni shells within the rotten wood powder in front of the wide open cavity of this beech tree during last Saturday's field trip at Hoyles Mill park.


26 May 2008

Punctidae

As explained in yesterday's post, I have written the introductory paragraphs for 2 North American land snail families to be included in a workbook being prepared for the terrestrial gastropods workshop during the upcoming AMS meeting in Carbondale, Illinois.

I posted what I had written for the Discidae in yesterday's post. Here is what I wrote for the Punctidae.

Punctum is a Holarctic genus. The North American Punctum species are among our smallest land snails. In fact, P. smithi, whose adult shell diameters barely reach ~1.2 mm, is one of the smallest land snails in the world. Punctum are primarily woodland snails that are widespread throughout North America. The range of P. conspectum extends to Alaska. Although Punctum specimens may, on occasion, be abundant in litter samples, because of their diminutive sizes, however, live Punctum are difficult to observe and study in the wild. Consequently, virtually nothing is known about the natural histories of individual species. The European P. pygmaeum is known to be able to reproduce without mating in captivity. The anatomies of most North American Punctum species have also not been studied.

Paralaoma caputspinulae (also known as P. servilis) is known from a few disjunct locations in western North America. It is probably a non-native species.
Any errors and significant omissions of information will be corrected before the final version goes in the workbook.

Punctum smithi was pictured in this post.


25 May 2008

Discidae

There will be a terrestrial gastropods workshop during the upcoming AMS meeting in Carbondale, Illinois. A "terrestrial gastropods introductory workbook" will be distributed during the workshop, which is currently being prepared. About a week ago, Kathryn Perez, one of the organizers of the workshop, asked, by e-mail, for volunteers to write short introductions for several North American land snail families. I volunteered to do any 2 of the 4 families I picked and she suggested that I write up the Discidae and the Punctidae.

Here is what I wrote for the Discidae and just e-mailed to Kathryn.

The genus Anguispira is endemic to North America. Anguispira are woodland snails. At least two species, A. alternata and A. fergusoni, characteristically climb trees in warm and wet weather, especially at night, to feed on fungi and rotting wood. Both A. alternata and A. fergusoni (and perhaps other species also) become dormant in the winter and laboratory populations of A. alternata are known to require exposure to low temperatures prior to reproduction. Increased winter temperatures due to global warming may, therefore, threaten especially the more southern populations of A. alternata. The known Anguispira species are conchologically variable, especially in spire height and peripheral angulation of the body whorl. In some cases, these variations may reflect cryptic species lumped under currently accepted taxa. The genus is in need of a taxonomic revision.

Discus is a Holarctic genus. Most North American Discus species live in forests; D. whitneyi inhabits wet meadows and marshy places. The European D. Rotundatus has been recorded in parks and disturbed areas in northeast and northwest U.S. and Canada.
Any errors and significant omissions of information will be corrected before the final version goes in the workbook.

Incidentally, A. alternata and A. fergusoni were 2 of the snails mentioned in today's earlier post.

Tomorrow I will post what I wrote about the Punctidae.


Gastropods of Hoyles Mill

Taking advantage of yesterday's nice weather, Megan and I explored Hoyles Mill Conservation Park in Montgomery County, Maryland.

Hoyles Mill is a secondary growth forest roughly 1 mile by 1 mile in dimensions. It is currently undeveloped, meaning that there are no roads, restrooms, offices, playgrounds, etc., within the park; there is only an unpaved road closed to traffic that goes alongside the park. The area will hopefully stay that way.

We found the usual mixture of introduced slugs and native species in apparent peaceful coexistence. Here is an Arion subfuscus, an alien originally from Europe, eating a mushrooom. The large circular hole is the slug's pneumostome, the breathing hole that leads into its lung.

HoylesMillArion

Frequent outcrops of large rocks broke the monotony of live trees and dead trees and leaf litter. At one spot, the creek flows over a massive single-piece rock that forms its bed.

HoylesMillCreek

Here is an assortment of the native gastropod species we saw. At the top is a Megapallifera species; bottom left is an empty Mesodon thyroidus shell next to a live juvenile; bottom right is a Ventridens ligera. We also found Philomycus carolinianus, another native slug and the snail Zonitoides arboreus.

HoylesMillGastropods

For me, the best discovery of the day was these live Anguispira fergusoni that Megan found on the underside of a rotting piece of wood.

HoylesMillAnguispira

This record extends the range of this species known to me about 2 miles south. Down along the Potomac River, about 6.5 miles south of here, Anguispira alternata is common. A long time ago, somewhere between here and the Potomac the ranges of these 2 Anguispira species must have approached each other and perhaps even overlapped. The intervening areas have since been heavily developed but fragments of some 2nd growth forests remain. It would be a stimulating endeavor to try to locate a place where the 2 species may continue to coexist.


23 May 2008

2 robin eggs that didn't make it

One of the most common, if not the most common, birds around here is the American robin (Turdus migratorius). The shell fragments of their bright blue eggs are frequently seen under the trees in the spring and summer.

RobinEggs

I saw these 2 robin eggs a week ago along a path near my house. They were about 2 meters apart when I first found them, but they were probably from the same nest. Although both had been punctured, the chicks were still inside.

RobinEgg

According to the information provided by the Cornell Lab of Ornithology (link above), on average, 40% of robin nests successfully produce young and only 25% of the fledged young survive to November. None from the nest we had above our mailbox last year survived to fledging.


22 May 2008

White-footed mouse on the towpath

WhiteFootedMouse1

What do the rat snakes that seem to be abundant in the woods along the C&O Canal eat? These white-footed mice (Peromyscus leucopus), probably.

This one ran onto the towpath out of the forest and just stood there looking at me. It didn't mind me getting closer and closer with the camera. After I took several shots, it ran into the grassy strip on the other side of the towpath. I followed it and took some more pictures before it finally disappeared in the undergrowth. Its body, without the tail, was only about as long as the anterior half of my index finger (~50 mm).

Butch Norden of the Maryland DNR, who confirmed the identification from this photograph, wrote in his e-mail: "This is the species that frequently comes into houses in the fall. It's also said to be a major carrier of the tick that carries Lyme Disease! Frankly, Aydin, this individual looks too young to be away from its mother and I doubt that its mature enough to fend for itself...Chances are the nest had been disrupted and it was confused."

Perhaps, its immaturity explains its unusual tameness. If its mother didn't recover it, the chances are a black rat snake did.

In the closest picture of it I noticed a brownish object (arrow) under its left eye. Is it a tick?

WhiteFootedMouse2

21 May 2008

Rat snake on the towpath

RatSnake1
Let my shoe provide a scale.

This long black rat snake (Elaphe obsoleta) was stretched motionless across the C&O Canal’s towpath last Saturday. Its frozen stance, a characteristic defense mechanism used by rat snakes, was probably in response to the potential threat I posed to it. It remained motionless, while I approached within about a meter or maybe less. Nor did it seem to mind the blinding flashes of light coming from my camera. A similar behavior was also displayed by this individual.

RatSnake2

One bicyclist showed up during the photo session. I let her know that a snake was blocking the path. Luckily, she wasn’t too terrified, passed behind the snake and continued on her way. The snake still didn’t move. Only after I walked away, did it start to crawl slowly and into the grass it went.

Many predators are probably more likely to spot a moving prey than a motionless one. Therefore, remaining motionless helps an animal escape detection. In this case, however, the strategy seems to backfire: the animal is exposed in the middle of a bare area where its dark body creates an easily noticeable contrast against the light background. Then again, the snake may now be mistaken for a tree branch. Such bare areas may indeed be present in the snake’s habitat, for example along river banks that are flooded frequently. So maybe this is not an example of an evolutionary trap.


20 May 2008

A mishmash meme

Deniz tagged me again. Since I ignored her previous tag, I'd better respond to this one, or she may never play Scrabulous with me again.

Forget the rules.

What were you doing ten years ago?
I don't remember.

What are 5 things on your to-do list for today (in no particular order)?
1. Commute to work in the rain. (It wasn't too bad.)
2. Rent a car to drive with Megan from St. Louis airport to Carbondale for the AMS meeting. (Done.)
3. Go on a walk after lunch. (Did it for 45 min.)
4. Post on the blog. (Doing it now.)
5. Play Scrabulous on Facebook with Deniz and Simla.

What are some snacks you enjoy?
Nuts! I probably get about a 4th of my daily calories from nuts, especially, the chocolate covered ones.

What would you do if you were a billionaire?
Cross out my name from the list of millionaires. Then I'd retire and wouldn't have to worry about commuting in the rain. I'd buy lots of books. Where would I put them though, we are already out of space for them. Establish a graduate student scholarship in my name to provide funds for the study of the evolutionary biology of mollusks. Buy real estate, buy stocks (diversify, diversify...). Give some to Deniz and Simla (the nieces). Buy more chocolate covered nuts.

What are 3 of your bad habits?
Pillage, plunder and loot (until I become a billionaire).

What are 5 places you have lived?
In reverse order some but not all: Germantown, Ann Arbor, Manhattan, Istanbul, Izmir.

What are five jobs you have had?
I have only had one real job, the current one with a U.S. Government agency, my entire life and I will probably retire from it after I become a billionaire. Previously, I had always been a post doc, a teaching assistant or a research assistant, etc.

What are the last five books you have read or been reading?
Sven Anders Hedin: My Life as an Explorer.
Madison Smartt Bell: Lavoisier in the Year One. (Reading it now.)
Kemal Tahir: Esir Şehrin İnsanları. (Reading it now.)
Zen Master Dogen: Enlightment Unfolds. (Reading it now.)
Mark D. Bertness: Atlantic Shorelines - Natural History and Ecology. (Reading it now.)

What are 5 4 websites that you visit daily (in no particular order)?
The Free Dictionary at least once, but usually several times a day. It's more fun to use now ever since they've added British pronunciations.
BBC News
Yahoo Comics
Weather in Germantown

I ain't tagging no one.


19 May 2008

Mr. Jarboe's store was closed today

JarboeStore1
Greenspeed Anura in front of Jarboe's Store. Did I miss the going out of business sale?

This ruin is adjacent to the C&O Canal at the entrance to the parking lot that marks the location of Edwards Ferry* that once operated across the Potomac River between Virginia and Maryland.

The blurb on the nearby information panel reads:
The crumbling Jarboe's Store remains here today. It was a general store and post office operated by Eugene E. Jarboe in the late 19th and early 20th centuries. Flood damage in 1996 forced the National Park Service to partially tear down the unstable structure.

JarboeStore2

*Although the correct spelling should be "Edward's Ferry", This is one of those phrases that is usually spelled without an apostrophe.


18 May 2008

Catoctin Aqueduct, or the lack thereof

CatoctinAqueduct4

Yesterday's C&O Canal trike trip took me to Catoctin Creek, at approximately mile 51.5*, where once the Catoctin Aqueduct carried the canal and the towpath across the creek. The aqueduct, which apparently had a faulty design, collapsed in 1973 (details here). The east arch of the aqueduct is all that remains in place. Unobscured parts of the arch are visible below and to the left of the bridge. The poster in the background in the next picture shows what the Catoctin Aqueduct looked like.

CatoctinAqueduct2

There is now a Bailey bridge spanning the creek. The metal frame of the bridge is held together by bolts visible in the above picture and clamp-like devices shown in the next picture.

CatoctinAqueduct3

There are now plans to restore the aqueduct (more info). I noticed several neat piles of large blocks along the towpath on the east side about 50 m from the creek. I suspect those are the recovered pieces of the aqueduct being readied for reconstruction.

CatoctinAqueduct1
Greenspeed Anura on the Bailey bridge. The bridge in the background is for trains.

*Locations along the C&O Canal are customarily expressed in miles from the starting point, mile 0, in Georgetown in Washington, D.C.


16 May 2008

Liriodendron tulipifera: a good place for snails

TulipPoplar1

One of the most common and easily identifiable trees in the forests of the northeast U.S. is the tulip poplar (also called yellow poplar or tulip tree), thanks to the characteristic shape of its leaves. In late spring, the equally unique, large flowers of the tree can often be seen on the ground, especially after rain storms when the flowers and small branches are easily broken off.

TulipPoplar2

Liriodendron tulipifera is neither a tulip nor a poplar, but a member of the magnolia family (Magnoliaceae). According to my tree book (C.F. Brockman, Trees of North America, 1968), the range of the tulip poplar extends from northern Florida to southern Canada. Tulip poplar trees can grow quite large. Here is a picture of me next to an enormous one at Belt Woods.

What makes this tree a favorite of mine is their tendency to develop large cavities at the bases of their trunks. The rotting wood that eventually develops inside the cavity provides food and the cavity itself provides shelter for land snails. Consequently, the soil from such cavities usually yields many specimens.


15 May 2008

Cat food is not just for cats

SlugsInCatFood

The past 2 mornings and evenings I have been seeing these slugs (Limax maximus) feasting on the bits and pieces left in the otherwise empty cans of cat food in the recycling bin that we keep outside our front door. And they were not the only ones in the can; one isopod is also in the picture.

If I can fatten up the resident Limax maximus on this high protein diet, perhaps they will perform more of their aerial matings this summer.


14 May 2008

2 noteworthy incidents from this afternoon's trike ride

While riding my Greenspeed Anura:

1. A chipmunk appeared on the sidewalk in front of me and then just sat there on its hind legs staring at me as I was approaching it fast. It probably had no idea what it was that was coming towards it. I had to swerve to one side to avoid hitting it just when it finally decided to dash away in the same direction. Luckily, it was faster.

2. 2 small dogs charged at me whilst barking furiously. Being at the bottom of a hill, I was going rather fast and they were headed straight towards the front tire. At the last moment they decided it wasn't such a good idea to splatter their puny brains all over me.

Note to self: Chipmunks are unpredictable; small dogs are nuts.


Does Jesus love extraterrestrial aliens?

According to today’s news reports (Reuters), the Vatican’s chief astronomer Jose Gabriel Funes said in an interview that "Just as there is a multiplicity of creatures on earth, there can be other beings, even intelligent, created by God...There could be (other beings) who remained in full friendship with their creator."

Considering the fact that here on our small earth there are so many "true" religions worshiping one or more gods, I would think that each planet that harbored life forms as intelligent as Homo sapiens would also be likely to have a multitude of belief systems.

If extraterrestrials vastly more intelligent and advanced than us landed on earth tomorrow and revealed to us that their religion, if they had one, was also vastly different from ours, would Father Funes consider giving up Catholicism and converting to their religion? If not, how would he explain that presumably the same god who he thinks also created the extraterrestrials gave them a different religion?

If something like that happened, could the earth-bound "true" believers continue to maintain, with a straight face, that only the particular religion that they had been most likely brain-washed into by their parents, was still the only "true" religion and that the extraterrestrials were in fact infidel heretics perhaps deserving to be burned at the stake?

It gets sillier and sillier everyday.


13 May 2008

Where do the old questions about dead birds go?

A while ago in this post, I and several commenters offered answers to the question, Where do all the dead birds go? The same question has now returned from the grave and is the subject of a recent post at the Bird Ecology Study Group.

I started reading the BESG blog a couple of months ago and it has since become one of my favorite blogs. I am not a birder and I get bored from looking at the seemingly endless species lists or just pictures of birds that I often see on few other primarily birding blogs that I regularly read. In contrast, almost all posts at the BESG blog have something to do with an interesting bird behavior and are accompanied with good, original pictures. I find them quite informative.

We need to have more blogs like that not just about birds, but about all other animal groups.


12 May 2008

Dissection of Truncatella caribaeensis - Part 2

Yesterday's post was about the removal of the shell of a Truncatella caribaeensis specimen in preparation for dissection. The subsequent dissection went well and I was able to see what I wanted to see.

Here is the dissected snail after the mantle was cut open and moved aside.

TruncatellaDissection4

The white, folded organ labeled "penis" is, well, the penis of the snail. It is about a half of the spiraled body length of the snail (talk about penis enlargement).

What interested me more was the row of tiny white flaps to the left of the penis. They constitute the ctenidium or the gill of Truncatella caribaeensis. Here is a larger view.

TruncatellaDissection5

This snail spends its entire life cycle on land very close to the sea, but out of it, unless it is carried away by the waves or the tides, and because of that it is considered a land snail. But it still, as we see here, retains the gill of its aquatic ancestors from whom it evolved. On the other hand, there are other species of snails that live on land alongside Truncatella, for example, Melampus bullaoides, that lost their gills a long time ago and obtain their oxygen thru their vascularized mantle, or "lung." But they nevertheless return to the sea to reproduce, because they still have planktonic larvae as did their ancestors.

Evolution works in mysterious ways.


11 May 2008

Dissection of Truncatella caribaeensis - Part 1

This is the 1st time I am dissecting a Truncatella specimen. In fact, this is the 1st time I am dissecting a non-pulmonate snail. Perhaps, I should have started off with a bigger species, but I need to learn about the anatomy of Truncatella for a research project and I don't want to waste time dissecting specimens that are not of interest now.

TruncatellaDissection1
Preserved specimen of Truncatella caribaeensis. The arrow points at the operculum.

The shell of this particular specimen of Truncatella caribaeensis was about 6 mm long. Since it is difficult to break apart the shells of such small snails without damaging the tissues inside, they are best eliminated by dissolving them in dilute acid. The carbon dioxide bubbles generated from the reaction of the shell material with hydrochloric acid proves that the shell is indeed made of calcium carbonate, in case there was any doubt about it.

TruncatellaDissection2

Here is the snail's body left behind after almost all the shell dissolved away. The arrow labeled m is pointing at one of the defining organs of the phylum Mollusca, the mantle (occasionally also referred to as the pallium). The snail's body is protruding from the mantle cavity, the space below the mantle. This proves that T. caribaeensis is indeed a mollusk, in case there was any doubt about it.

TruncatellaDissection3
m: mantle, t: tentacle; s: snout; f: foot. The scale is in millimeters.

Now I will start the actual dissection. If I don't botch it, I will write about it in a future post.


A genuine pain in the ass: proctalgia fugax

I was awakened this morning around 4:30 by a mild case of proctalgia fugax, a type of rectal pain that usually strikes at nite during sleep. Its causes are unknown (if other medical conditions are ruled out) and there is no treatment for it. Luckily, I get them very infrequently, once a year, maybe.

Last nite's episode was, fortunately, a mild one; the pain was of a dull, aching type. However, it was uncomfortable enough to prevent me from going back to sleep and I got up. I walked around the bedroom, went downstairs and came back up, did some stretching and squatting. I figure that if the pain comes when I am in bed, then getting up and moving around should help ease it. The pain did lessen rather quickly. I went back to bed and was able to fall asleep again until about 7:30 when Marissa Cat woke me up. It was way pass her breakfast time.

She will be there again tomorrow morning, but hopefully, proctalgia fugax won't return for a long time.


09 May 2008

Calvin's 500-story gastropod


Calvin and Hobbes by Bill Watterson

Deniz sent this comic a few days ago. I forwarded it to some friends. Megan e-mailed back this response: "Being a slug on the usual scale, capable of navigating, climbing up, and squirming through a miniature natural neighborhood, would be much more enjoyable than being a monstrous slug on the scale of a city block!" I am not sure if I agree with her. There could be some satisfaction to be had from coating an entire city with slime.

But the real question is "Can a snail or slug grow that big?" And the answer is no. First, I can't think of an adaptive reason for the evolution of a monstrous gastropod from much smaller ancestors. Second, a 500-story snail would need to consume a heck of a lot of calcium carbonate to build itself a decent shell. Third, whenever and wherever such a humongous gastropod crawled, it would lose, in the form of mucus, a heck of a lot of water. Now, imagine a population of such behemoths. They would scrape down hills of limestone, drink up lakes full of water and eat up an entire tropical forest in one afternoon. The next day, they would run out of resources and be extinct by the evening.


Go ahead, buy yourself an award

It is absurd if one has to pay for an "award" that one is supposed to have earned. If an award costs you money, then it is not a real award, but a gimmick the real purpose of which is either to make you sort of feel good about yourself or to make money for those who are giving the award. An example of the latter is the scientific "awards" sold by the International Biographical Centre that I wrote about in this post.

An example of the former kind is currently being promoted by the U.S. Government. I work for a Federal Agency. Towards the end of March, a circulating e-mail at work invited everyone to sign up for an exercise promotion program called The President's Challenge. The idea behind the program is to get people to be more active physically, which is a good thing. I exercise everyday anyway, so I signed up. Apparently, we are competing against other offices in my agency. All I have to do is to remember to enter my activities in an on-line log book, which gives me points based on the type, intensity and duration of the activity. So far, so good.

Then I learned that I could even get a personal award, but only if I paid for it. The individual awards are rather cheap, only a few dollars each (order form). But it's the idea of having to pay for an award that makes it ludicrous. If they really want to reward those who may have started exercising thanks to this program, then they should give them awards without making them pay for their awards. It just wouldn't feel the same to me if I had to say, "I logged in 40,000 points in The President's Challenge and then I bought myself this medallion."

But If you think otherwise, don't let me curb your enthusiasm, go ahead, jog to the nearest, or better yet, the furthest sports store and buy yourself a trophy. Congratulations!


08 May 2008

Future revealed in mucus

Young ladies! Are you wondering about the names of your future husbands? Wonder no more! Your prospects are written in strings of slimy, sticky exudates. Right. And all you need to attain this giddy piece of knowledge is a...snail (but definitely not a reptile).

George Benn explains it all in The History of the Town of Belfast, with an Accurate Account of Its Former & Present State; to which are added a Statistical Survey of the Parish of Belfast, and a Description of Some Remarkable Antiquities in its Neighbourhood (1823):

On May eve, when the sun has gone down, it is customary for young damsels to go forth to the fields in a body, when each of them procures a living snail or a bunch of yarrow, from either of which it is in their power to discover (by a method which has received the sanction of the most prudent and knowing matrons) the names of those who are to be their partners through this "breathing world." The process is simple. A dish or platter, whether of earthen ware or wood it matters not, is placed over the body of the unintelligent reptile, which has free liberty to exercise its nimbleness on an arena of meal or sawdust, the exact dimensions of the prison house in which it is thus most innocently incarcerated. Though the snail be not reckoned the most active of the animal creation, yet neither is it altogether disposed to a state of perfect quiescence, and as in all its movements it is well known to leave a shining "pledge behind," so in its rambles when in bondage during this critical night, the faculties of the creature are miraculously enlarged, and it is found to trace with singular precision some two or three letters of the Roman alphabet which form the initials of the name of some future happy helpmate.
At the end, there is no questioning of the snail’s declaration.
If at any time, however, a mischievous or an incredulous person should have an opportunity of pointing out any superfluity in the inscription (a case not absolutely impossible), his objection is readily and justly obviated by claiming due allowance for the flourishes of so expert and tasteful a scribe.
But don’t blame the poor snail if you one day end up with an unintelligent reptile for a husband.


06 May 2008

Running against the wind down the irrational alley

Many years ago, my mother had an older friend who had a rather dark complexion, because her father was a descendant of the African slaves employed by the Ottomans, mostly for domestic work, until the late 19th Century. Sadly, this woman had never accepted her heritage or come to terms with her skin color; instead, she was forever resentful to her mother for having married that dark-skinned man, her biological father. It apparently never dawned on her that she was a unique and chance product of those 2 special people and that had her parents never mated with each other, or even, for example, if they had happened to have mated on another night she would not have been born.

What made her mentality especially disturbing to me was that she taught biology at a high school. Imagine having her as a teacher.

Nevertheless, I had always assumed that this woman’s distorted notion of her identity was an isolated case and that most normally intelligent adults would not fall into the same logical trap.

Just recently, however, I came upon another example, but this time in a fictional setting. A couple of weeks ago, I started reading the Turkish author Kemal Tahir’s novel Esir Şehrin İnsanları*. One of the secondary characters in the book, a Turkish man, visits his ex-wife, an Italian woman who, years earlier, had taken their small daughter and left him. The man goes out to lunch with his daughter, now in her late teens. She doesn’t recognize him and is instead under the impression that he is a friend of her father. During lunch, the man asks his daughter what she thinks of her father.

She became sullen. She said she couldn’t comprehend how her mother had done such a wrong thing...A Turkish father...
I can only hope Kemal Tahir, often labeled an intellectual, was aware of the absurdity of the young woman's thinking.


*People of the Captive City, first published in 1956, is a novel about the incipient nationalist movement in Istanbul after the 1st World War when the city was under British control. As far as I know there is no published English translation of it. A Turkish account of Tahir's life and works is here.


05 May 2008

Another Chrysemys picta

ChrysemysPicta1

This Eastern painted turtle was on the C&O Canal towpath last Friday afternoon when I was returning from my limestone and snail expedition.

I had never examined one of these turtles this closely before. The bright red patches on its legs and tail were striking.

ChrysemysPicta3

When it saw me approaching, it withdrew into its shell and refused to come out. All I wanted was a nice shot of its head. I had settle for one of its snout instead.

ChrysemysPicta4

Back in April, I wrote about a juvenile Eastern painted turtle that I had found by a lake near my house. That one, perhaps because it was still naive, was actually braver than this much bigger one and didn't hide its head away from me.


Isopods on flickr

Think of an obscure, esoteric object or activity and the chances are there is a group devoted to photographs of it on flickr. After all, there are groups for battered old chairs, three legged-cats [sic] and balancing eggs on top of other eggs (2 members and 2 photos as of today).

But believe it or not, until about 3 months ago no flickr group existed for isopods, my other favorite animals. So, I created one. We are now up to a total of 3 members, including myself. Of the 22 pictures in the group photo pool, most are mine. And those have all been used to illustrate the posts about isopods on Snail’s Tales.

Isopods may never become as popular as Turkish oil wrestlers, but I am hoping the group will continue to grow.


04 May 2008

A trip to find Potomac marble and snails

Where the rocks and soil are rich in calcium carbonate, there are likely to be lots of snails, because snails build their shells out of calcium carbonate. Unfortunately for me, however, calcium carbonate containing rocks are rare where I live in Maryland. So, when I recently read in Mike High's The C&O Canal Companion (1997) that outcrops of a limestone conglomerate called Potomac marble could be seen at a location along the C&O Canal, I headed for the spot late Friday afternoon.

I parked my car at the Monocacy Aqueduct and got on my trike to travel on the canal towpath. My destination was a place called Camp Kanawha about 5 miles upstream from the aqueduct and reached from the towpath by a short trail that goes over the train tracks. Here is the entrance to the camp surrounded by boulders of Potomac marble. It was just like the description in High's book.

CampKanawha

And here is a close-up of the rocks. I didn't have my acid bottle to test the rocks for calcium carbonate, but they are definitely a type of conglomerate.

PotomacMarble

I did a brief search along the bases of the rocks for snails. Here are the 4 species I found, clockwise from the lefthand corner: Gastrocopta armifera (live), Pupoides albilabris, Ventridens ligera (live), Stenotrema sp. The photos are not to scale; Gastrocopta and Pupoides were about 4 mm long, while Ventridens and Stenotrema were larger, about 7-8 mm wide.

PotomacMarbleSnails

The soil along the rocks was soft and damp and there was plenty of plant cover, providing an ideal habitat not just for snails but also for earthworms and all sorts of arthropods. Can you spot the tiny mite below and to the right of Pupoides albilabris?

It's not possible to evaluate the snail species richness of a location from a 10-min cursory "survey". But I suspect there are many more species to be found around rocks of Potomac marble. One confounding factor in this case is that crushed limestone is used as ballast under railroad tracks and if snails were indeed abundant at this particular location, it would be difficult to determine if the contributing factor were the presence of Potomac marble or railroad limestone, which was abundant.

Here is the MARC train taking commuters to Point of Rocks, the next station only a mile away.

Marc&Anura

03 May 2008

Trike repair - Episode 1

It's been only about 2 weeks since I bought my Greenspeed Anura and I already had a flat tire yesterday. This morning I set to work to do something I hadn't done in maybe 40 years. In fact, although I have faint childhood memories of watching the neighborhood kids repair their bike tires, I don't recall if I ever repaired a flat of my own bike. Relying on those distant teachings, information I had printed from the Internet from this site and the live advice given by my good friend Ümit via cell phone, I tackled the problem like a true novice and overcame it in just about 2 hours, which includes the time spent taking photos and talking on the phone.

AnuraFlat
Thanks to Ümit's insight, I was able to repair the inner tube without removing the front tire.

Part of the reason why it took so long was that the "offending substance" turned out to be a minuscule piece of metal protruding from the inside of the tire; I could feel it with my finger, but not really see it.

TinyMetalPiece

Its removal required one of my dissecting forceps and the magnification provided by a 7x Hastings triplet. Here it is on the palm of my hand. It was 2 mm long and barely a quarter of a millimeter wide, but strong enough to create a pin hole thru the inner tube.

The inner tube has now been patched up and the trike is back in working condition. If the tire remains inflated, I will take it out for a ride this afternoon.

Until the next episode, peace be upon you.


02 May 2008

Poison ivy & fungi

PoisonIvy&Fungi

How do you decide what to read next? - Part 1

Deniz the Niece asks this question on her blog. To me, this is a 2-tiered question. First, how do I decide which books to buy? And then, how do I decide which book from among those on the to-be-read-shelf-o'-books to read next?

Rarely do I buy books at regular prices from ordinary bookstores; it seems that the only time I do that is when I am in Turkey. Most of the books I buy are discounted books from on-line bookstores, primarily Amazon. Recently, I bought several sale books from the NHBS Environment Bookstore in England. I had picked those books by going thru their sale catalog on their web site. That being the case, I usually don't go to bookstores to look at books. So, how do I decide which books to buy?

The problem is once I buy and read a book, I usually forget why I had decided to buy it to begin with. An example is Sven Hedin's My Life as an Explorer (1925) that I recently finished reading and wrote about in several posts. I started reading that book last February after it had been in the to-be-read-shelf-o'-books for about a year. I don't recall how I got the idea to buy that book (from Amazon). I must have either read a review of it somewhere or read about Hedin himself in an article and then searched for his books.

Speaking of reviews, I have bought some books that I had first read about in blog posts. So, keep posting those book reviews, folks.

The only bookstore that I visit regularly, well, once every other month or so, is the local "friends of the library" bookstore that sells used books at ridiculously cheap prices for the benefit of the local public libraries. There, however, what I buy is the outcome of 100% chance. I have bought books from them mostly because they were so cheap and that I wouldn't have bought at full prices elsewhere (example). I figure, even if I don't like the book at least I am supporting a good cause.

I will answer the 2nd part of the question some other time.


01 May 2008

Spiderman outside the office window!

WindowCleaner1

No, wait, never mind, that's not the spiderman. It's only a window cleaner. OK, back to work, everyone.

WindowCleaner2