31 January 2008

Get your papers embossed here

I spent the afternoon at the National Museum of Natural History in D.C. I was at the Mollusk library for several hours looking up stuff. As I was getting ready to leave, I noticed this ancient contraption on a shelf.

Bartsch1

I took it down, slid a piece a paper under the brown disk and push the lever down. The raised image it created on the paper was for the library's Bartsch Collection.

Bartsch2

Paul Bartsch (1871-1960) was a malacologist and a curator in the Division of Mollusks of the National Museum of Natural History from 1914 to 1946. (Back then, the museum was called the U.S. National Museum.) After Bartsch died, his collection of books was probably given to the museum's library.

30 January 2008

Story of a complex drink

Last December Andrea Illy, Chairman of illycafe and a chemist by training, gave a lecture titled The Science of Coffee at the New York Academy of Sciences. The podcast of the lecture is here.

It is an informative presentation if you don't mind using your imagination every time Mr. Illy says "On this slide you will see..."

Some highlights:

• Coffee originated in Ethiopia where "tiny" wild coffee plants still grow in forests.

• An average espresso cup has 40 mg of caffeine, while an average filtered cup of coffee has 120 mg of the same.

• The 2 main coffee species in cultivation are arabica and robusta (there used to be 80 spcies in cultivation). The latter is less flavorful but has more caffeine.

• Humans apparently have a "kind of" self-regulating physiological limit to caffeine consumption: too much of it curbs further intake.

• The flavor of coffee is due to the chemicals generated during roasting of the beans. The 2 main chemical processes are the Maillard reaction* and the degradation of polycyclic compounds present in green beans.


*Takes place between amino acids and reducing sugars, not between carbohydrates and sugars as Mr. Illy claims in a moment of confusion.

29 January 2008

Sleeping Triodopsis

DormantTriodopsis1

During my post-lunch walk today, I found some dormant snails under a rotting piece of plywood. All I can tell about their identity is that they are a species of Triodopsis, but figuring out the exact species—usually from the subtle differences in the positions of the apertural teeth—will take more effort than I can put in now.

Every single one of the 8 adult snails had its aperture covered with a thin membrane-like layer of dried slime and was partially buried in soil with its umbilicus up, which is the preferred position of snails hibernating in soil (I don't know why).

I decided that it was a good idea to mark the snails* so that I can check up on them throughout the year. Come to think of it, I should go back there tomorrow and look for some juveniles to mark. That way I can get an idea of how long they live. The beginnings of a little project? Maybe.

Here are the marked snails before I turned them over and placed them in their little depressions in soil under the plywood.

DormantTriodopsis2

*Behind their lips with red ink from a Staedtler Lumocolor pen that is, according to its labeling, lightfast and waterproof. We shall see.

28 January 2008

A muddled ecology of landscapes

The back cover of Eco-Geography (Lindisfarne Books, 2001) identifies the author Andreas Suchantke in his own words as a "freelance ecologist" with backgrounds in zoology and botany. I happened upon this book in the used bookstore and thought I'd give it a try. Suchantke has an easy to read style and the book was well-translated from German by Norman Skillen.

Eco-Geography is a collection of loosely connected essays on animal and plant ecology, the place of humans in nature and evolution. The emphasis is on African habitats, but there is also a chapter on New Zealand. Suchantke appears to be a follower of Rudolf Steiner, whose name occasionally shows up in the book. I am not familiar at all with Steiner's ideas, so I can't tell how much influence they may have had on Suchantke's thinking.

Suchantke has some valuable ideas and I have already quoted him in a previous post. A problem about the way he presents his ideas, however, is that he has a tendency to stray off from the main topic into marginally relevant fields. For example, the chapter titled "Africa: Three Landscapes as a Single Organism" starts off with the application of the "organism concept" to the landscapes of Africa. But in the middle of the chapter, this discussion is more or less interrupted by a 5-page digression, first, about the Pygmy anatomy and then about western industrial cultures. I suspect those are the parts where Rudolf Steiner's philosophy enters the discussion. Likewise, chapter 5, "Juvenilization in Evolution and Its Ecological Significance", presents a good, brief explanation of paedomorphosis, the evolutionary process of the retaining of juvenile characteristics in adults, then veers off to a discussion of the replacement of forests with agricultural fields and unfortunately ends with a distorted view of nature conservation:

This newly created landscape, however, may be described as artificial only in a very superficial sense. In reality it is just as much a product of natural process as it is an artifact, for in shaping it humans merely intensify a development that had already been begun by nature. There can be no question, then, of humans acting contrary to nature—certainly not while they are involved in developing a fertile and ecologically diverse agricultural landscape. Quite the reverse—they are acting as nature acts.
I disagree and am sorry that Suchantke, to top off his praise of the African landscapes, couldn't come up with a more coherent message.

Also posted in a slightly different form at Amazon.

27 January 2008

Zen flesh, zen bones, zen cat

Ever since I had a chance encounter with a Buddha on a Montreal street last October, I have developed an interest in zen. The size of my zen library, previously consisting only of Alan Watts' The Way of Zen, was doubled a week ago when I picked up this little book, Zen Flesh, Zen Bones, at the used bookstore. It is a compilation by Paul Reps of many short zen "stories", translated from the Japanese by Nyogen Senzaki and first published as 3 separate books in the 1930s. The 4th chapter was published as a magazine article in 1955.

ZenBook1

One thing I enjoy about a used book is seeing the previous owner's name in it. This book had at least 2 previous owners, Rick Bisbee and Mary Olson, who left their names on the inside cover.

ZenBook2

I have no idea who they were and when they may have read this book; no printing date is given for this edition.

I like reading the stories in the book at nite before going to sleep; some make sense, some don't, which is, of course, the case with everything else in life. Here is the very first one:

ZenBook3

The scribbling at the bottom seems to be in Mr. Bisbee's handwriting, who apparently understood how one needs to go about learning zen. That is, if it is indeed what one needs to do.

And here is Temi enlightening herself with the essence of zen.

ZenCat

25 January 2008

Some insignificant thoughts on statistical versus biological significance

Statistics books often remind us that the statistically significant differences between sets of data may not necessarily have practical significance. The emphasis on practical significance is probably due to the heavy use of statistics in comparisons of different procedures with practical applications in medical and industrial research.

I know of only one book, David Heath's An Introduction to Experimental Design and Statistics for Biology (UCL Press, 1995), that discusses, albeit briefly, biological significance as opposed to statistical significance:

…a statistically significant difference is not necessarily biologically significant. By this we mean that it may not be interesting from a biological point of view or useful from a practical point of view. The reason is that in actual fact the null hypothesis [that the samples being compared are identical] is probably never likely to be true! Animals in two different places are almost certain to be slightly different in size and seeds treated in two different ways are almost certain to have slight differences in germination times. If you took big enough samples, you could probably find statistically significant differences in almost any experiment or investigation, but this would not necessarily mean that the differences were biologically meaningful.
In the late 1940s and the early 1950s, Harold W. Harry (1921-1995) worked on the tiny land snail Carychium exiguum for his Ph.D. thesis. But for reasons unknown to me, the bulk of his thesis was not published until after he died*. There are a lot of shell measurements in Harry's thesis that were not analyzed with proper statistical methods, probably because of the way most biological research was done back then and also because computers were not available.

Recently, I started analyzing Harry's shell measurements of C. exiguum. I don't have access to Harry's raw data, which may not exist any more anyway. Luckily, however, Harry gave (in Table 11 of his thesis) the number of shells, range, mean and the standard deviation for 38 lots he had measured. For starters, I looked at the shell dimensions of 4 samples of C. exiguum collected at one station in Cheboygan County, Michigan between July 1949 and July 1950.

HarrysData

I thought the means for these 4 samples, all being from one station collected over a span of about a year, could be averaged into one set of data. But to make sure, I compared the mean shell heights using one-way analysis of variance (ANOVA). (Even when the individual measurements are not available, ANOVA can still be applied to the summary data.)

To my surprise, ANOVA revealed that there was a statistically significant difference (p=0.003) between the mean shell heights of the 4 Cheboygan samples. This is when I started thinking about biological significance as opposed to statistical significance.

The absolute difference between the mean shell heights of sample R1 (the largest mean) and sample R3 (the smallest mean) was only 0.041 mm! This is not only small in absolute terms, but also in a relative sense, corresponding to a difference of only 2.1%. The absolute and mean differences between the means of the other lots were even smaller. Could a mean shell height difference of 2.1% have any biological significance for the occupant snails under any circumstance? The answer depends on what we mean by biological significance.

What exactly is biological significance?

1. A variable (and measurable) phenotypic trait that confers a selective advantage (or a disadvantage) at certain quantities will be biologically significant when the same quantitative differences between individuals are statistically significant. Therefore, biological significance implies evolutionary significance.

2. Biological significance is not a fixed attribute of certain individuals. Biological significance is spatially and temporally variable; differences between traits within a population that are biologically significant under one set of external conditions may not be significant under another set of conditions.

3. Biological significance is a probabilistic attribute. For example, a predator may selectively kill smaller prey most of the time, but it may also kill larger prey occasionally.

4. Biological significance is a continuous attribute, for it can't be defined with respect to a strict cut-off point or an absolute limit in the quantity of a phenotypic trait. For example, in the case of the shell size of C. exiguum, it would be meaningless to claim that only the size differences larger than 0.1 mm were biologically significant. We can only hypothesize that biological significance increases as the size difference increases.

5. Biological significance does not necessarily imply an evolutionary advantage for larger, stronger, faster individuals. Partly due to the trade-offs associated with many phenotypic traits, being large, strong, fast, could be disadvantageous under some circumstances and, in contrast, being small, weak, slow could be advantageous under other circumstances.

6. The trait differences between individuals within a population could be as biologically significant as those between individuals from different populations of a species. Statistical tests compare population (actually, sample) means, but in real life it is the individuals that compete against each other.

As for Harry's C. exiguum shells from Cheboygan County, I don't think that the mean shell height difference of 2.2% could have had any biological significance for the occupant snails.

Furthermore, the shell height ranges of all 4 samples of C. exiguum completely overlapped (see the table above). It is difficult to find biological significance between the dimensions of shells in 2 or more samples when not only the means but also the minimums and maximums of all the lots are very close to each other or identical. In fact, the shell heights of the largest and the smallest individuals in sample R1 differed by 0.56 mm. If there was any biological significance between shell dimensions, it was probably between the largest and smallest snails within lots. Those would have been the individuals that made up the fractions (~4.6% of the population) that were about 2 or more standard deviation units away from the sample means.

So, why do we get differences between samples collected at a given location at different times? I can think of 2 explanations:

1. What we are seeing are the results of sampling errors.

2. The mean shell dimensions of a population of a snail (or any other animal) species may indeed fluctuate randomly or may go thru regular or irregular cycles. Such fluctuating or cycling quantities may or may not be biologically significant depending on the circumstances. To establish their biological significance it would be helpful to consider: (1) long term temporal trends in the data; (2) short term drastic changes in the environment.

Part 2 in this series is here.


*Harry, H.W. 1997-1998. Carychium exiguum (Say) of Lower Michigan. Walkerana 9(21):1-104.

23 January 2008

This is what the Pirahã do to a Christian

Daniel Everett, chair of Languages, Literatures, and Cultures at Illinois State University, and his wife went to Brazil in 1977 as missionaries to convert
the indigenous Pirahã people to Christianity. In an interview in the 19 January issue of the New Scientist, this is what he tells of his experience among the Pirahã:

They lived so well without religion and they were so happy. Also they didn't believe what I was saying because I didn't have evidence for it, and that made me think. They would try so hard to understand what I was saying, but it was obviously utterly irrelevant to them. I began to think: what am I doing here, giving them these 2000-year-old concepts when everything of value I can think of to communicate to them they already have?
It was a mind opening experience for him:
Their concept of truth also changed my entire religious persona. I went from being a Christian missionary to an atheist.

22 January 2008

A friend went to Nigeria and all I got was igbin* shells

Achatina1

When a Nigerian friend of the family was leaving for her home country in December, I asked her to bring back some snail shells. About a week ago, she returned with these shells. I am not familiar with the taxonomy of giant African snails, but I am assuming these are Achatina achatina.

Achatina2

These snails had been collected last December in the town of Isua-Akoko in Ondo State of Nigeria. My friend said they lived in forests, but since she wasn't the one who had collected them, I couldn't get any more specific locality information from her. But when she revealed that they had actually consumed the hapless snails that once occupied these shells while they were still in Nigeria, I got her to give me an abbreviated description of how she prepared her snail dish. I don't think I will ever cook snails, but it's good to know such things. Next time the subject of cooking giant African snails comes up at a party, I will have something to say. So, here is how she did it.
She boiled the snails for about 10 minutes, then removed them from their shells. Then she rubbed and washed them with lime juice (or whatever citrus fruit was available locally) to remove the slime. She cut the cleaned snails into small pieces and then boiled them again, but this time with vegetables, some sort of local melon and hot peppers to create a soup.
When I asked her if they ate the entire snail, she didn't know how to describe the parts they discarded. So I drew a picture of what a snail removed from its shell would look like and she pointed at the organs that would be in the spire of the shell.

A review of a Nigerian restaurant in Brooklyn in the Village Voice, described the texture of the cooked Achatina as "unbelievably rubbery". Thank you very much, but if I am ever in Nigeria, I think I will stick to vegetables and melons.

*The word for snail in the language of the people of Isua-Akoko.

21 January 2008

Peace & tolerance: brought to you by your priests

thecity21i08
The City by Derf.

The original news of the scuffle, which took place late last December, is available at the BBC and Times Online. Watch it on YouTube.

Religion at its best. What more can I say?

20 January 2008

Why is nature study so popular in Great Britain?

I have always been impressed by the number of natural history books, especially on invertebrates, that have been published in Great Britain and jealous of the numbers of natural history clubs they have. Sometimes, I have even wished that I had been living in GB just so that I could have been involved in some of that activity, while avoiding the shipping charges that I pay to have books sent here. And at the same time, I have always wondered why most other countries seem to have lagged behind the British in those respects. Not only in countries like Turkey, where serious study of nature by laypeople is unheard of and by professionals is elitist and superficial, but even in the U.S. the state of affairs is way behind GB.

A recent podcast from the BBC Natural History Unit tries to answer the very same question. The narrator Francesco da Mosto interviews several natural history personalities in GB. Among the various ideas they propose to explain "the British passion for the natural world" are the Industrial Revolution's origin being there (by David Attenborough), the founding of the Royal Society for the Prevention of Cruelty to Animals in 1824, the laws enacted for the protection of wild life in the 19th century and the encouragement given to the working classes to participate in nature study (all by Robert Lambert) and the higher likelihood of people encountering wildlife in a "small" island like Great Britain (by Les Stocker). At the end of the program, however, no clear consensus emerges, which is not surprising to me, because I don't think there could have been just one responsible factor. There were probably many interconnected developments that kindled and directed the British society's ongoing love affair with nature.

Also interviewed is the malacologist Robert Cameron, one of the authors of the standard citation "Kerney & Cameron, 1979", which is, of course, their classic A Field Guide to the Land Snails of Britain and North-West Europe. Dr. Cameron talks about the early days of the Conchological Society, the origin of his interest in snails, how he discovered the snail Leiostyla anglica in the Channel Islands during a vacation, the edible snails (Helix pomatia and Cornu aspersum) the Romans introduced to England ("the fast food of the 4th century A.D.") and how the range of Cepaea nemoralis seems to have increased recently (could it be due to global warming?). His explanation for the popularity of natural history is that in GB in the 19th century there was a large middle class with leisure time. Dr. Cameron's comments are scattered thoroghout the podcast, so you have to listen to the entire program not to miss them. This is not to mean that the rest of the podcast is to be skipped; it is entertaining and educational in its entirety.

Incidentally, my 2 favorite bookstores from across the Atlantic are the Pemberley Natural History Books and the NHBS Environment Bookstore.

16 January 2008

15 January 2008

Gastrocopta contracta

GastrocoptaContracta1

This is probably one of the most widespread and abundant Gastrocopta species in the eastern U.S. According to Pilsbry (1948), its range even extends into Mexico and Cuba. It is also one of the smallest; the shell of this particular specimen was 2.4 mm long.

GastrocoptaContracta3

Although Say, in 1822, described this species as Pupa contracta, he thought it probably belonged to Carychium. Carychium is, of course, a basommatophoran genus. All basommatophoran snails have their eyes at the bases of their tentacles. (Here is a basommatophoran Melampus bullaoides.) Gastrocopta is, on the other hand, a stylommatophoran with its eyes at the tips of its tentacles, as you can see in these pictures.

GastrocoptaContracta2

One peculiar characteristic of G. contracta and many other Gastrocopta species I have seen is that the shells of live snails usually have bits of soil stuck to them. I don't know if that serves a function and how the debris sticks to the shell. Is their periostracum sticky or is the snails' mucus somehow involved in the process?

14 January 2008

For a given volume, the smallest surface area is...zzzz

Last Friday afternoon I underwent one of the rituals of middle age: a colonoscopy. I figured I'd use the rare opportunity of being anesthetized in a constructive way by playing mind games with myself. So I spent the last couple of hours before leaving for the hospital studying several pages from R. M. Alexander's Optima for Animals (1996). The idea was to see how much of the material I was reading I would remember afterwards. The very last problem I studied was about determining the height to diameter ratio that gives the minimum surface area of a cylindric can with a fixed volume. The solution is obtained as follows.

The surface area (S) of a cylinder in terms of its diameter (D) and volume (V) is given by the following equation.

S = (πD2/2) + (4V/D)

The 1st derivative of this with respect to D (at a given V) is

dS/dD = πD - (4V/D2)

Replacing V in the 2nd term by its equivalent (πHD2/4), where H is the cylinder's height, gives

dS/dD = πD - πH

At a minimum, dS/dD must be zero, which can happen only if H = D. It follows that for a given volume, the smallest surface area of a cylinder is obtained when its height is equal to its diameter, or when the height to diameter ratio is one. (More detailed discussions of this problem are available here and here.)

About 3 hours later as they were hooking up the various monitors to my body in the operating room, I was repeating to myself: for a given volume, the smallest surface area is obtained when the height is equal to the diameter. Then I was asked to turn to my left side and I heard the anesthesiologist announcing that he was hooking up the anesthetic. A few seconds later, I could feel that I was losing consciousness. I closed my eyes and quickly repeated to myself one more time: for a given volume, the smallest surface area is obtained when the height is equal to the diameter....

I woke up with an intense abdominal pain from all the air they had pumped into my intestines and at the same time I heard the nurse trying to get me to pass gas ("push, push, or else I have to use the rectal tube"). But the first thing that came to my mind was for a given volume, the smallest surface area is obtained when the height is equal to the diameter. I was so excited that I could remember it! Like a mantra, I started reciting it loudly and slowly so as not to mess it up (I was still not fully awake) and all the while trying to pass gas and burp to relieve the pain. A few minutes later when the doctor showed up to give me his verbal report, I greeted him with a carefully worded: for a given volume, the smallest surface area is obtained when the height is equal to the diameter. He said, "That's pretty good, but not quite accurate. For the smallest surface area, the height has to be greater than the diameter." I said, "No, they have to be equal. I learned it before I came here." He was adamant too, "I studied chemistry like you did" he said, "The height has to be greater than the diameter."

Then, he told me the good news: No polyps were seen, everything appeared normal. And I don't have to go thru this ordeal again for 7 years!

Now I am wondering if the good doctor was confusing diameter with radius, which being a half of the former, indeed needs to be smaller than the height. Maybe I should send him a couple of pages from Alexander's book.

13 January 2008

Whites Ferry

WhitesFerry3

This afternoon I went back to the C&O Canal, this time to the Whites Ferry area south of the Monocacy Aqueduct. Whites Ferry is a small car-carrying flat-bottomed boat that goes back and forth between Maryland and Virginia covering a rather short distance across the Potomac River along a cable. In the picture below you can see the ferry's cable behind it.

WhitesFerry1

After watching the ferry for a few minutes, I took a 4-mile hike on the C&O Canal. Sections of the canal around there still contain water, but not deep enough for the boats that were once pulled by mules treading on the towpath alongside the canal.

C&OCanal5

The remains of what appeared to have been a yellow and black bird were next to the towpath. It looked like a lucky predator had dined on the unlucky bird. I have no idea what species the bird may have been.

DeadYelloBird

At one location there were lots of osage oranges on the ground in the woods along the towpath and also in the canal.

OsageOrange1

According to this article, the osage orange's original native range was rather small, covering parts of western Arkansas, southern Oklahoma and eastern Texas. But the tree was introduced to many places in the U.S. as a hedge plant. It is interesting that a plant can do so well in places so far north of its original home.

OsageOrange2

11 January 2008

The current pile of books

A recent list Deniz the Niece had on her blog of the books she was reading prompted me to write about the ones I have been reading. Like Deniz, I could be reading several books at a given time (not simultaneously, of course). Some I read while commuting to and from work, some I read in bed before going to sleep and some I read for my research, which could be at any time of the day.

Without further ado, here is my current reading list not in a particular order.

CurrentBooks

At the bottom of the pile is the compilation of the best cartoons of one of my favorite cartoonists Roz Chast, Theories of Everything (2006). They are absurd and hilarious and make me fall asleep with a smile on my face.

Above it is the classic Between Pacific Tides, first published in 1939 by Ed Ricketts and Jack Calvin. This is the 5th (1985) edition by David W. Phillips. It is all about the intertidal and subtidal creatures of the western coast of the U.S, but mostly in and around Monterey Bay where Ricketts lived and worked. I have been reading it slowly for several months now.

3rd from the bottom is A Guide to Extreme Lighting Conditions in Digital Photography by Duncan Evans (2006). A useful book, but the title is a bit misleading, because most of the guidance is not for the taking of pictures, but for their subsequent manipulation in Photoshop.

Next is a recent (2004) and easy-to-read yet scholarly account of The First Crusade by Thomas Asbridge. My favorite bad boys of history, the Crusaders, already debuted on this blog.

Then comes a Turkish book, Osmanlı Tarih Lügatı by Midhat Sertoğlu (1986). This is an encyclopedic dictionary of terms from the Ottoman history. Most entries are related to the organization of the Ottoman government, but there are also geograpical and biographical ones. I like to pick it up every now and then and read a few pages at random.

Above it is Eberhard Sauer's The Archaeology of Religious Hatred (2003). An interesting book; but it is a little difficult to read, because of Sauer's dense style. Were the Christian zealots behind all those headless statues we now see in museums? I will write more about it after I finish it. [Note added 4 March 2008: Here is my review of it.]

The following book, Eco-Geography by Andreas Suchantke (2001), was a chance (and cheap) encounter in the used bookstore. Apparently a follower of Rudolf Steiner, Suchantke writes about landscapes, mostly in Africa, and their animals and plants all interconnected. I will write a detailed review of the book upon completing it.

The Turkish author Halid Ziya Uşaklıgil's (1866-1945) İzmir Hikayeleri (Izmir Stories) is next. These are apparently true stories from a bygone era, Uşaklıgil's childhood in the city of Izmir in the 1870s and 1880s.

The thick blue book is another classic, Fretter & Graham's British Prosobranch Molluscs (2nd ed., 1994). It is jam-packed with morphological, biological, behavioral information about the non-pulmonate gastropods of Great Britain. And you don't have to live over there to justify curling up with this one on a cold and rainy winter nite.

Finally, a disappointing entry, Steve Jones' the Single Helix (2005), a collection of short essays previously published in the Daily Telegraph. Jones is a biologist who has worked with snails. So I was excited when I first heard about this book. Alas, these essays are too superficial and too tied in with contemporary occasions to have significant lasting value. Any scientific insight is almost non-existent. And despite the cover photo, only a few have anything to do with snails. In the preface Dr. Jones writes: "On looking back I am depressed to see how many of those columns [in the Daily Telegraph] were devoted to carping, the age-old prerogative of the academic, with complaints about cash mixed with generalised ill will. Such grumbles soon become dull and none has made it to this book." I think many made it to this book. There you have my review of it. Now I am going to post it on Amazon too.

While piling these books up, I noticed something curious. Why are the names of the books and authors on the spines of Turkish books written "backwards", that is from the bottom to the top?

10 January 2008

I have a beard, so listen to what I'm saying

IstanbulBook
You may have to set the encoding of your browser to Unicode (UTF-8) to display the Turkish characters.

Asırlar Boyunca Istanbul (Istanbul Throughout the Centuries) by Haluk Şehsuvaroğlu is a Turkish book from the 1950s that was given out free by the newspaper Cumhuriyet. As was often the case with books published in Turkey during that period, it has no publication date anywhere on it as far as I can see. But one of the artists who drew some of the many pictures in the book luckily put the year 1954 after his name, giving us an idea of approximately when the book may have been published. The copy I have, a legacy from my father, is in a bad shape: the covers are ripped, the pages have been yellowed, are coming loose and worst of all, crumbling.

As its name implies, this 250-page, folio-sized book is about the history of Istanbul. It is quite informative, but one problem with it is that for many of the essays no literature sources are given. So you just have to take the author's word for what he is claiming to be true stories. The book consists of a rather haphazard collection of articles, some several pages long, while others covering only a few sentences, on topics ranging from the tombs of Ottoman sultans to the various types of beards that were once popular in the city.

sakal2

According to Şehsuvaroğlu, during the Ottoman times, a beard was considered to be a symbol of wisdom and experience and those who were assigned to certain government positions were required to grow a beard. Thus, there was an appropriate saying: Sakalım yok ki sözümü dinleteyim (I don't have a beard to make people listen to me). Another saying along the same lines was sakalı ele vermek (literally, to give your beard to someone), which meant to become subservient to someone.

Şehsuvaroğlu claims that the candidates considered for the position of şeyhülislam, the head of the religious affairs in the Ottoman Empire, were required to have at least some patches of white hair in their beards. In that case, a relevant saying would have been sakalı değirmende ağartmak (to let one's beard turn white in a flour mill), which meant to grow old without becoming wise, presumably the implication was that what was making the person's beard white was only flour.

sakal1

Şehsuvaroğlu lists the names of popular beard styles, including: top (ball), çember (wheel), süpürge (broom), tahta (wooden), torba (bag), yelpaze (fan), tinton (your guess is as good as mine) and kaba (coarse). Apparently, this is what a kaba beard was supposed to look like:

sakal3


Would my beard (and ring) have given me any clout if I had travelled back in time to the Ottoman period?

09 January 2008

Grab a beer and run

Moderate alcohol drinking combined with regular exercise are good for one's health. That's the take home message from a study by Pedersen et al.,* published today in the European Heart Journal. The last 2 sentences from the paper:

But neither physical activity alone nor alcohol intake can completely reverse the increased risk associated with physical inactivity and alcohol abstention. Thus, both physical activity and alcohol intake are important to lower the risk of fatal IHD [ischaemic heart disease] and all-cause mortality.
The favorable influence of moderate alcohol consumption on overall mortality clashes with the perception that ethanol is a carcinogen. If it is likely to cause cancer, how can it reduce overall mortality at the same time? Last fall, the World Cancer Research Fund/American Institute for Cancer Research released an Expert Report Food, Nutrition, Physical Activity and the Prevention of Cancer: a Global Perspective. They were aware of the contradiction of their findings with those of numerous studies pointing out the cardiovascular benefits of moderate alcohol consumption. In the preface to the Expert Report, Michael Marmot wrote:
"WCRF also appreciated the parallels between dietary causes of cardiovascular disease and cancer. There is a great deal of concordance. In general, recommendations in this Report to prevent cancer will also be of great relevance to cardiovascular disease. The only significant contradiction is with alcohol. From the point of view of cancer prevention, the best level of alcohol consumption is zero. This is not the case for cardiovascular disease, where the evidence suggests that one to two drinks a day are protective. The Panel therefore framed its recommendation to take this into account."
Their summary recommendation for alcoholic drinks was simple: Limit alcoholic drinks.

I walked an hour earlier today. Now I can enjoy a beer. Cheers!


*Jane Østergaard Pedersen, Berit Lilienthal Heitmann, Peter Schnohr, and Morten Grønbæk. The combined influence of leisure-time physical activity and weekly alcohol intake on fatal ischaemic heart disease and all-cause mortality. Published today in the European Heart Journal. (Full Text Free Access).

08 January 2008

Arthur C. Clarke's prophecy

The author Arthur C. Clarke turned 90 last December and to mark the occasion, released a video of himself on YouTube. In 1 December issue of the New Scientist there was also an interview with him. Clarke, who is apparently as addicted to email as everyone else, has a somewhat dismal prognosis for our cultural future, which he calls the "fractal future".

"Although everybody is ultimately connected to everybody else, the branches of the fractal universe are so many orders of magnitude away from each other that really nobody knows anyone else. We will have no common universe of discourse. You and I can talk together because we know when I mention poets and so on who they are. But in another generation this sort of conversation may be impossible because everyone will have an enormously wide but shallow background of experience that overlaps by only a few per cent."

I don't quite agree with him on that. As a person who adopted Sri Lanka, a developing, non-western country, as his home, he certainly wouldn't be expecting everyone to be familiar with only the Western culture. If anything, the Internet may be helping people to be more familiar with all the other cultures on earth. And along those lines, the Internet, by connecting people with overlapping experiences and interests who would otherwise never have a chance to interact with each other, may be creating virtual cultures where the backgrounds of experience of the participants may be overlapping almost completely.

Besides, most people worldwide have had shallow backgrounds of experience—whatever that means—since times immemorial anyway. And that's not going to change.

07 January 2008

Strobilops aenea

StrobilopsAenea2

Strobilops aenea is one of my favorite snails. They are tiny—the shell of this individual was 2.3 mm across—with prominently ribbed dark brown shells.

StrobilopsAenea1

The coloration of the body is not unique to this genus. There are species in other genera with a similar dichotomous color pattern: dark upper surface with dark tentacles and white sides and tail.

But the conical shape of the shell is characteristic of Strobilops aenea and most of the other species in the genus. I don't know of any other North American land snail genus with a similar shell shape.

StrobilopsAenea3



And now for something completely different: fossilized shit coprolites at the Virginia Museum of Natural History.

06 January 2008

Where all that money goes

I have decided to spend all of my money on books, journals and photographic equipment (and also on beer and chocolate covered marzipan).

To implement my plan, I have renewed my subscriptions to the Invertebrate Biology and Basteria and started a subscription to the Journal of Conchology. I will soon be renewing my subscriptions to the Zoology in the Middle East and Triton. Moreover, I just became a member of the Florida Academy of Sciences. They publish this neat journal called the Florida Scientist.

I also get the New Scientist and the Archaeology, but they are not up for renewal for a while.

I will soon be ordering some books and a new flash for my camera. But now I am off to buy beer and chocolate covered marzipan.

03 January 2008

Science Illustrated: A new popular science magazine

The Bonnier Corporation of Denmark, the publisher of Popular Science and several other magazines, now has a new bimonthly: Science Illustrated. From its contents and lay-out, I believe SI is targeted at lay people with no or little science background. And it would indeed be a good magazine for them. The 1st issue covers a lot of topics using many, many good photographs and drawings; in addition to longer pieces, there are also numerous easier-to-read informative snippets. Some of the topics covered are, however, of the run of the mill variety. How many articles about T. rex or the Titanic hitting an iceberg can one read before reaching the saturation point, really?

I was sent a free copy of the 1st number, January/February 2008. I enjoyed looking at it, but decided not to subscribe. Fascinating though science is, it is not just flashy pictures and stories of exciting discoveries. Science, by its very nature, incorporates a lot of uncertainty and controversy. But I see little of those aspects of science in this magazine and perhaps because of that the coverage appeared a bit superficial to me. I recommend that the editors of SI do some copying from my favorite magazine, and to which I subscribe, the New Scientist.

02 January 2008

Beaver's tree and the sleeping snail - updates

Yesterday, on the 1st day of the new year, I went on the 1st field trip of the new year. On my way out, I passed by the spot where 12 days earlier I had photographed a standing tree the trunk of which had been gnawed all the way around by a beaver. The beaver had since returned and finished its business.

BeaversTree2

Being beavers, they are always busy in that area, but I am yet to see one in action.

On my way back, I stopped at the place where also 12 days earlier I had found a dormant Haplotrema concavum in a little hole in the soil. To my delight, the snail was still there yesterday.

HaplotremaConcavum2

I will be checking up on it again.

01 January 2008

Top 10 nature moments of 2007

A meme that started out at Earth, Wind & Water and came to my attention at A DC Birding Blog.

1. My topmost nature moment in 2007 was watching and photographing the entire mating process of a pair of Limax maximus in my backyard last summer. I still haven't posted the pictures here, though.

2. Two incidents both involving the climbing habits of isopods, in one case up the bird bath in my backyard and in the other up the wet trees in Antwerp, kindled my currently developing interest in those creatures.

3. Getting bitten by a mantid!

4. Observing the 3rd eye of Cerithidea scalariformis.

5. Witnessing the gruesome, but all natural demise of the caterpillar that had been munching on my tomato plants.

6. Late one nite in Antwerp last July, we were walking thru a park, I turned on my flashlight and there were slugs all around us.

7. Discovering a large cache of empty snail shells at a location not too far from where I work. Eventually, I ended up collecting more than 300 of them some with traces of graffiti paint.

8. Discovering a frog mummy on a sidewalk.

9. Getting acquainted with the tidal flat snail Ilyanassa obsoleta in Chincoteague. Expect more posts about them.

10. You can take me away from nature, but you can't take nature away from me unless you have a pair of tweezers.