30 September 2006

Temi is 18


Fluffy Temi turned 18 in September. Although she is not the fast and agile cat that she once was, she is still in pretty good shape. Her diabetes has been under control (thanks to daily insulin injections), she eats well and enjoys the backyard on nice days. This is a picture of her taken early in September.

We hope to have her with us many more years!

29 September 2006

Buy this book!

mollusksbookA new book about our favorite animals, The Mollusks, edited by Sturm, Pearce and Valdés, has recently been published by the American Malacological Society (AMS). The book is for serious collectors, amateur malacologists and anyone else who wants to learn more about one of the most successful animal groups evolution has produced.

One reason why you should consider buying this book is that yours truly wrote one chapter (23, rearing terrestrial gastropods) and co-authored (with Tim Pearce) another (22, terrestrial gastropods). Another, and perhaps a much better reason to spend your money on this book is that the revenue from the sale of the book will support the scientific program, student scholarships and grants administered by the AMS.

Moreover, this is a good book. As the editors point out in the introduction, each chapter was peer-reviewed (I know my chapters were and not just once but several times). There is a lot of practical information on collecting, raising mollusks and properly maintaining a collection, even picking the right paper for your labels so that they will still be intact and readable long after your bones have turned into dust. There are chapters on most major mollusk groups written by specialists for nonspecialists as well as on cladistics, fossil mollusks and conservation. One thing this book won't help you do is identify your specimens, which is not what it was written for.

But no book is perfect and no book review is complete without criticism. Unexplainedly missing in this book is a chapter on opistobranchs, the sea slugs, even though some lesser known mollusk groups, for example, the aplacophorans, are rightfully included. Also needed are an index and a general outline of molluscan classification to explain to the uninitiated the phylogenetic relationships between the different mollusk groups discussed in the book.

Finally, in our age of digital photography, chapter 7 discussing in great detail film photography is curiously outdated and the shorter chapter 6 on digital imaging is quite inadequate.

These shortcomings aside, you won't regret buying this book. The table of contents and ordering information are available on the AMS website.

28 September 2006

Why tripe is digestible

In each issue, the British science magazine the New Scientist publishes questions submitted by readers along with answers, also provided by readers, to previously published questions. Back in June, they published an answer I had submitted.

In this week's issue (No. 2570), a reader inquires how tripe, a portion of the stomachs of ruminants, can be digested by humans when a stomach is normally not digested by its own gastric juice.

I figured this time I will get ahead by posting an answer here rather than send it to the New Scientist.

The reader presumably assumes that there is something intrinsic in the cellular structure of tripe or any other kind of stomach that resists digestion. In reality, however, what protects the inside of a stomach from its own acid and pepsin, an enzyme that hydrolyzes proteins, is the coating of mucus that lines the inside wall of the stomach. This mucus layer, secreted by special mucus cells in the stomach wall, prevents the acid and enzyme molecules from reaching the cellular wall of the stomach.

But once a stomach is removed from a dead animal, cleaned, chopped into pieces and cooked, there is no more protective mucus left and it is as digestible as most other edible tissues.

27 September 2006

Eastern tiger swallowtail

eastern swallow  tail caterpillar

This is the 4th instar of the eastern tiger swallowtail (Papilio glaucus). I photographed it one recent evening in the woods after a late afternoon rain. It was climbing up the wet trunk of a young beech (I turned the picture sideways for your viewing pleasure).

According to Wagner (Caterpillars of Eastern North America, Princeton Field Guides, 2005), the graded lightening of the sides of this caterpillar's body from the top to the bottom is an example of countershading. This makes the parts that would receive less light appear about as light as the top receiving more light, thus rendering the caterpillar more uniform in color and, consequently, more difficult to be detected by visual predators, such as birds.

And, of course, this is what the adults look like.

eastern swallow  tail

26 September 2006

Naughty sparrows


Last summer, we spent 2 days in the town of Gömbe in southern Turkey. One morning we arranged for a tractor to take us to the mountain behind the town where we wanted to collect land snails. So there we were sitting in the wagon of our tractor in the middle of the town waiting for someone to finish doing something. (It seems that when you are with a large group, you are always waiting for someone.)

Luckily there were plenty of urban birds around to keep us and our cameras busy. I have already posted about the swallows and their nests. We also spotted these mating house sparrows (Passer domesticus) on some electric cables below the overhang of a roof. My more bird-savvy companions quickly identified the birds and distinguished the male from the female (not that I didn't know that the male bird was the one on top). The male (left, below) is easily identified by its dark bill and breast in comparison to the pale colors of those of the female (right).


25 September 2006

Weekend's snails and other creatures


First there was this Ventridens ligera, a common snail around here. I found this one under some leaves at a very wet spot in the afternoon. There was a long metal pipe inserted into the side of a hill. A long time ago, when the area was farmland, the water coming out of the hill emptied from the pipe into a now rusted, crumbling tub; it was most likely for the farm animals to drink. The farm is long gone, the area is now a park and the pipe is dry, but water still seeps out from among the rocks. Disappointingly, however, my search yielded only this snail.

One nite, after the rain ended, I sneaked into the woods (the park closes at sunset). On such warm, wet nites, I invariably see Anguispira fergusoni climbing on tree trunks. They seem to feed on rotten wood, or perhaps on the fungi that grow on and within such wood, as this one seems to have been doing.


Later, this eastern red-backed salamander (Plethodon cinereus) made a brief appearance in the light of my headlamp before disappearing into the darkness. According to White & White (Amphibians and Reptiles of Delmarva, Tidewater Publishers, 2002), there are 2 color morphs of this salamander, the red-backed morph, which is what this one is, and the lead-backed morph. In a previous post, I had a picture of the lead-backed morph.


24 September 2006

A deer, a racoon and maybe a fox


I took this picture yesterday at a muddy spot along the shore of Little Seneca Lake in Black Hill Regional Park not too far from my house. This must be a popular feeding station, for there are superimposed tracks of 3 mammal species: a white tailed deer (yellow arrows), a racoon (green arrows) and a single paw print of possibly a fox (red arrow). Immediately to the left of this spot was a shallow inlet of the lake and both the deer and the fox tracks were disappearing across the inlet.


The above is a closer shot taken from the side. One deer print is on the left, a series of racoon prints are on the right and the fox print is in the middle. The later could instead be a dog print, but I suspect a dog would have left more prints and there would also have been associated human foot prints as there are no stray dogs around here.

22 September 2006

A long story from 1838 to 1979

What do the British explorer, archaeologist Charles Fellows (1799-1860) and my college diploma have in common? No, we didn't go to the same school. To find out, read on.

Fellows started out the first of his several expeditions in western Turkey in search of archaeological sites1 in 1838 from Izmir on the west coast. He traveled north to Çanakkale, crossed the Dardanelles and continued on to Istanbul. From there, first he went east, then south to arrive at a small town the name of which he spelled as Oneóenoo. Fellows noted that the town was at the foot of a cliff with caves in it. This description identifies Oneóenoo as Inönü (= cave front).

John Arrowsmith's 1844 map of Turkey had Inönü as "In Oghi" (arrow). (Downloaded from the David Rumsey Historical Map Collection)

After its brief debut in Western literature in Fellows' account of his trip first published soon after he returned to England, the town of Inönü went back into oblivion until 1921. In January of that year, the fledgling army of Mustafa Kemal confronted the occupying Greek army in their first full-scale battle on the plains below Inönü. The Turkish army was commanded by a veteran soldier, Colonel Ismet, who like most others in his country did not yet have a last name. At the end of March, Ismet returned to fight the Greeks one more time in the 2nd Battle of Inönü.

inönüpul2Now we fast forward to 1934. War had been over for more than 10 years, Mustafa Kemal (soon to have the last name Atatürk) was the first president of the still-young Republic of Turkey. He and the General Assembly passed a law making it mandatory for all subjects of the Republic to have last names. Ismet, quite naturally, picked as his last name the name of the town where he had commanded the Turkish armies; he was now Ismet Inönü. After Atatürk's death, he was to become the 2nd president of Turkey. His likeness is on the old Turkish stamp on the left.

Ismet had a son, Erdal, who became an accomplished physicist. Towards the end of the 1970s he was the dean (dekan (deacon) in Turkish) of the science faculty at Bogaziçi University In Istanbul where I was an undergraduate studying chemistry. I graduated in June 1979, but my aversion to pompous celebrations made me skip the graduation ceremony. A few days later I showed up to pick up my diploma. But the secretary realized that the dean hadn't signed it. Luckily, Inönü was in his office and wasn't busy. She ushered me in, I presented my diploma and the man whose father had picked their family name as that of the town where he had fought 2 battles more than 80 years after Fellows had visited the same place signed it.

This is a scan of a photocopy of my college diploma. I have no idea where the original is. Erdal Inönü's signature is at the lower right-hand corner.

1. Fellows, Charles. 1852. Travels and Researches in Asia Minor, more particularly in the Province of Lycia. Two Parts. London: John Murray. [The Elibron Classics Replica Edition. 2004.]

19 September 2006

The infallibility of the stupidity of being a pope

Generally speaking, all religions have resorted to violence and oppression to introduce and continue their dominance and will do so again if and when need and opportunity arise. It is the nature of their dogmatism.

Having made my point on that issue, I will now look into a current BBC article that discusses the issue of the fallibility of papal statements and asks the question "How infallible is the Pope?"

Before a pope, or any other person for that matter, can make an infallible statement, he or she must have an infallible notion. And once a person has an infallible notion, it doesn’t matter whether or not it is spoken; an infallible notion is an infallible notion. Keeping an infallible notion a secret doesn’t make it a fallible notion.

The BBC reports that "According to [papal historian Michael] Walsh, it is thought Pope John Paul II wanted to speak infallibly in 1994 when he ruled out the possibility of women ever being ordained, but was advised against it."

This means, assuming things did happen that way, two things:

1. Pope John Paul II thought he had an infallible notion. Since he was the Pope and he thought he had an infallible notion, then he must have had an infallible notion.

2. Because his advisors stopped him from revealing his infallible notion, either they thought the Pope’s notion wasn’t infallible, which, however, couldn’t have been the case, or they figured it was best that the Pope kept his infallible notion to himself.

But, whenever a pope, any pope, has an infallible notion, doesn’t that imply that God, in a sense, has revealed this infallible notion to him? And if he is prevented from proclaiming that infallible notion to the rest of the Catholics, isn’t he acting against God’s wishes? But since John Paul II wasn’t turned into a salt pillar as far as we know, does that mean he thought he had an infallible notion when, in reality, he was mistaken?

Let us leave the resolution of such delicate issues to Catholics who are on low-salt diets. I will instead ponder upon a much more important question. When a pope says “This is not an infallible statement” is he lying or telling the truth?

18 September 2006

Snail tracking


Taking advantage of the last days of the summer, my son and I went on a nature hike in the woods yesterday afternoon. While passing by some small, shallow pools alongside the creek, I noticed these tracks on the submerged rocks. I suspected snails and sure enough, a couple of the tracks each ended at a small roundish object that indeed was a snail about 5 mm long.


I am guessing that they are juvenile Helisoma anceps, a planorbid snail (family Planorbidae). Although they are strictly aquatic, these snails actually have lungs and are in the subclass Pulmonata along with many strictly terrestrial snails. The planorbid snails have evolved an accessory gill, the pseudobranch, that helps them extract oxygen from the water.


We may return to the creek later this afternoon to collect some of these snails with the purpose of raising them at home for a while. I am hoping to take photographs of the snails themselves.

16 September 2006

Yucky charcoal

moldy charcoal

I had no idea charcoal could get moldy until a couple of weeks ago when I found these mold-covered charcoal pieces in this container that we had been keeping in the backyard. Apparently, rainwater had leaked into the container creating an environment ideal for mold growth. In retrospect, it makes sense that mold could grow on charcoal, which is incompletely burned wood or some other substance rich in organic matter.

We had invited a friend over for barbequed chicken this evening. But these moldy charcoal pieces, which were also damp and crumbly, would not heat up. So, we resorted to sausages grilled on an electric grill. At least the wine was good.

14 September 2006

Zoning of the snails

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The picture above shows the shore of a small island in the Aegean Sea off the western coast of Turkey. During a brief visit to this island last July, I made some very preliminary observations on the mollusks that live there.

I marked on the picture 4 distinct mollusk habitats or zones. Zone A is the broadly defined marine habitat proper that I will not discuss further. At the opposite end is the zone D, the terrestrial habitat proper. Regarding that zone, I will only mention that we found a few land snail shells on the island mostly under the small rocks and in small depressions in the ground filled with plant debris. What I was more interested in at that time as I am now are the 2 zones between A and D.

Zone B is a transition habitat. There are no discernible tides in the area. So the water level in zone B stays more or less the same except during rough weather and storms. But, even on calm days as in the picture, the water level constantly oscillates by about 10-15 cm.

The picture below shows those mollusks of zone B that I could spot while I was there and also in the photos later. The large snail (#1) is Monodonta turbinata. There are also limpets (#2) and chitons (#3) that I can’t identify further. I am sure there were other less visible, smaller mollusk species perhaps in the clumps of green algae that grow closer to the sea.


Zone B is a physically harsher habitat than zone A. Compared to the latter, the water temperature is probably more variable, there is more solar radiation and wave exposure and some risk of desiccation. As you can see in the picture, the limpets and chitons tend to stay in small depressions where they are probably protected from waves and drying and perhaps even predators. Most snails, on the other hand, always seem to be on the move, slowly gliding across the rocks.

Despite its physical shortcomings, one main advantage of living in zone B may be the relative scarcity of predators. There are no fish; crabs probably frequent the area, although I didn’t see any while I was there.

The harshest zone of them all is the zone C. It is totally dry except during rains and storms and in the summer the rock surface is not only dry, but also gets hot in the sun; very hot indeed. Also note that during rains, any marine snails in zone C are exposed to freshwater. Furthermore, there are no plants growing; it is basically barren rock probably with some microscopic algae on its surface.

Therefore, one wouldn’t expect to find any mollusks in zone C. In fact, from a distance it does appear lifeless. However, a closer look reveals not just a few, but many, many small snails attached to the rock surface. You can see 2 clusters in the picture below.


These snails, the shells of which were about 5 mm high, are littorinids (family Littorinidae). I am not good at identifying them, but I suspect these are Littorina neritoides. I noticed that like their more terrestrial distant relatives these snails also aggregate when they are aestivating. But I don’t know why.

Life at seashores, rocky or not, provide important clues to the evolution of terrestriality among gastropods. The littorinids, about which I have written before (here, here and here), have made it from zone A all the way up to zone C, but not yet to zone D.

A good introductory book on the subject of the biology of rocky shores is, well, The Biology of Rocky Shores by C. Little and J.A. Kitching (Oxford U. Press, 1996).

Note added 15 September: Henk Mienis has noted in an e-mail that Monodonta turbinata is now Osilinus turbinatus and Littorina neritoides is Melaraphe neritoides.

12 September 2006

Mites might make mosses multiply

Many marine organisms release their gametes into the water and let the currents bring them together. Although this seems like a wasteful practice, it obviously offers advantages over presumably more costly mechanisms, especially in sessile organisms, that would be necessary to bring the males and females together. Likewise, many terrestrial plants rely on winds or insects for the transport of their pollen from the male to the female parts.

A recent report in Science1 presents evidence indicating that mosses may also have evolved at least a partial dependency on microarthropods, including springtails and mites, for the transport of sperm from the male to the female structures when there is no connecting water film in which the sperm would otherwise swim.

Cronberg et al. showed that in the laboratory female mosses separated from male mosses by 2 cm and 4 cm would be fertilized only when there were springtails and mites present.

Sporophyte production in female moss patches in presence versus absence of springtails or mites. Figure from Cronberg et al.1

Now it is necessary to demonstrate that this phenomenon also takes place in the wild.

Is there a case in which the reproduction of one animal species depends on the transport of its gametes by another animal species?

1. Nils Cronberg, Rayna Natcheva, and Katarina Hedlund. Microarthropods Mediate Sperm Transfer in Mosses. Science 313:1255 (2006). Abstract

11 September 2006

Saturday's snails


I went to the C&O Canal area last Saturday to photograph snails. My specific destination was the pond pictured above. I had been there during the Potomac Gorge Bioblitz last June. This is where Tim Pearce found Pomatiopsis lapidaria during the Bioblitz. I wanted to photograph them in their habitat and while searching for them, I found other snails as well. I will post on P. lapidaria on another occasion, but here are a couple of the other snails I saw.


This is a juvenile Mesodon thyroidus, a rather common species around here. Those dark spots that may appear to be on the shell are actually on the snail's mantle; they show thru the shell, because the shell is more or less transparent. We had already recorded this species during the Bioblitz.


But the little Vertigo (only about a couple of mm long) was a nice surprise and a new record for the area. I found both species on the mud within a meter of the edge of the water. The area is visible in the pond picture at the far end towards the left. Based on its habitat, I am suspecting it is Vertigo ovata, a species of wet, muddy places.

I also photographed the new canal boat.

09 September 2006

New boat in the lock


Today I went to the C&O Canal to photograph some snails. It turned out that it was the inauguration day of the new canal boat. The previous boat had a fun name: The Canal Clipper. They gave the new boat a boring name, Charles something. Whatever...


In the first photo you see the boat going into the Lock 20 in front of the Great Falls Tavern Visitor Center. Once the boat is in, the guy with the hat closes the gate.


As you can see, the boat fits into the lock tightly. Now they are waiting for the lock to fill with water. Those things that are sticking out from under the awning are not exhaust pipes; this being a special day, there was a band sitting in front of the boat. They didn't play much, though.


This is the other end of the lock. It is almost fully filled and the boat has risen.


Finally, the front gate is open and the couple of mules on the towpath on the right have started to pull the boat. You would think that 2 mules would have a hard time pulling a rather big boat loaded with fat people, but they are pretty good at it.

Once the boat is out of the lock, the actual trip in the canal is rather short (the boat doesn't go thru any other lock). Today's trip seemed especially short; I think they only went out for about 200 m before turning back.

But it is fun to watch the entire operation. Put it on your list of things to do the next time you are in the area.

(I'll post the snail photos on Monday.)

08 September 2006

A book for cloudy days


I had been a cloudspotter and didn’t know it. While reading Gavin Pretor-Pinney’s The Cloudspotter’s Guide (Penguin Books, 2006), I kept remembering the cloud-related posts I have been putting up on this blog. The latest one of which was about a snail that prefers to look at clouds from above.

I was delighted to learn from this book that the taxonomy of clouds follows a Linnean system, with genera, species and varieties, similar to that used for animals and plants. Depending on the atmospheric conditions, clouds conforming to the definition of one species can even change into other species, evolve so to speak, just as do animal and plant species. Is it a coincidence that the branching clouds I once observed out of my airplane window reminded me of cladograms that one frequently encounters in papers on evolutionary biology?

The book is divided into many, many sections, some of which are only a page or two long. Each section can be read more or less independently of the others without having to worry too much about discontinuity. That and the many photographs and diagrams make it an easy-to-read book.

Moreover, there is something interesting on almost every page ranging from scientific explanations of various atmospheric phenomena to cloud related snippets from art, history and culture. For example, I learned that the “explanation” that thunder was the sound of colliding clouds that my mother told me when I was a little boy goes all the way back to Aristotle. Who would have guessed that Mom was dispensing Aristotelian wisdom all those years right under our noses!

One complaint I have: why are all the distances and heights in this book in feet and miles? Is it because I am reading the U.S. edition?

A little more than a year ago, I had a post inspired by the ephemeral and one-of-a-kind shapes of some clouds passing above my house. Thanks to this book, now I know those were Cumulus humilis. Clouds may not stick around for very long, but The Cloudspotter’s Guide is going to have a permanent spot in my library.

The author, Gavin Pretor-Pinney, is also the founder of The Cloud Appreciation Society.

06 September 2006

Channel of Constantinople


I took this picture last July a few minutes after we had taken off from Istanbul. We were flying north (to the left in the picture) over the Black Sea, the land below is Turkey and the narrow channel in the distance towards the east is the Bosphorus that separates Europe from Asia.


Before I examined John Arrowsmith's 1844(?) map of Turkey in Europe (downloaded from the David Rumsey Historical Map Collection), I didn't know that another name for the Bosphorus was the Channel of Constantinople. (In Arrowsmith's map, north is towards the top.)

The Symplegades ("Clashing Rocks"), made famous by Jason and the Argonauts, are assumed to have been located at the northern opening of the Bosphorus (see map here). I believe the Cayennees Islands (a.k.a Cyanean Rocks) marked in Arrowsmith's map are the Symplegades.

05 September 2006

I saw her thru the bathroom window


Near the end of our trip in Turkey last July, we spent a couple of days as guests of my cousin and his family in the western town of Foça. One morning, as I was minding my own business in the bathroom, I looked outside the window and spotted this lizard on the wall of the neighbor's house. I ran out, grabbed my camera and ran back in to take a couple of photos. It was apparently a Laudakia stellio.

One study1 that involved the killing of 91 of these lizards in southern Turkey determined that they ate mostly insects. Even though I am citing it, this is a type of study that I don't condone. There is no excuse in killing so many animals just to see what they were eating. If I were a journal editor, I would refuse to publish these sorts of studies.

As reported by Mienis2, these lizards also prey on land snails. Mienis made his determination from the analysis of fecal pellets of lizards.

1. Düsen & Öz. 2001. A Study on the Feeding Biology of Laudakia (=Agama) stellio (L. 1758) (Lacertilia: Agamidae) Populations in the Antalya Region. Turkish Journal of Zoology, 25:177-181. pdf
2. Mienis. 1990. Predation on landsnails by the lizard Agama stellio in Israel. Zeitschrift für angewandte Zoologie, 77:253-256.

04 September 2006

Hygromiids in the pot

Indoor hygromiids doing the usual

The land snails in the family Hygromiidae are widespread throughout the Mediterranean countries. Many species in the family have the habit of climbing and aestivating on tree trunks, bushes, stems of grasses, herbaceous plants and on walls.

It is usually claimed that these snails climb on objects to avoid the higher temperatures found on and near the ground in the summer (for example, see Mienis, Pallidula 30:21-22, 2000). That does make sense, but may not be the only answer or the right answer.

Several years ago, I kept several hygromiids in captivity in a large pot filled with soil. The species included Cernuella virgata, Xerolenta obvia and Xerocrassa cretica (below). Because I was aware of their climbing tendencies, I had erected several dry lily stems in the soil. The snails, kept mostly indoors at about 22 ºC and away from direct sunlight, spent most of their active and dormant time on the stems. One December day when it was raining lightly and the outdoor temperature was about 9 ºC, I placed the pot with 6 snails in it outside. About an hour later, 5 of the snails were crawling on the stems and one was on the soil (there was no standing water in the pot).

Xerocrassa cretica: the snail from D28

These observations suggest to me that it isn't just the summer heat that makes these snails climb. Their climbing habit appears to be genetically controlled; they climb regardless of the weather. But why exactly they climb, I don't quite know.

03 September 2006

Chick in the water


Last July during our expedition in southwestern Turkey, we spent 2 nites in the small town of Beyağaç. One late afternoon a group of us went on a nature hike thru a vast open rocky field cut by a shallow creek. When we were crossing the creek we noticed this tiny plover chick sitting motionless in the water.

While we were photographing the little birdie, a noisy adult plover appeared and started flying around us in wide circles. As the twilight was settling down on us, it finally landed on a pile of rocks and I was able to take some shots of it using a telephoto lens. From these pictures, my companions later identified the bird as the little ringed plover (Charadrius dubius).


When we returned to the spot where we had seen the chick about 10 minutes earlier, it was gone. Perhaps, it had walked away.

More information on the little ringed plover is available at Birdguides.