Dress to Impress

Have you gotten your Halloween costume all picked out? What are you going to be this year?

I was interested in journal articles about Halloween practices and so did a quick literature search. Mostly I came up with articles about whether and how we should inspect and X-ray the candy kids get when they go trick-or-treating. Instead of choosing that necessary but creepy topic, I picked a study on the partying habits of college students on Halloween.

If you've been to college, lived around a college, or just know anything about college students then you know that many students use...how shall I put it?...mind altering substances. In 1988, 90% of 18 to 25 year olds had tried alcohol, 65% were considered current alcohol users, 56% had tried marijuana, and 15% were considered current marijuana users. This same age group also reported having tried or used other drugs such as cocaine (20%), stimulants (11%), and sedatives (5%). This study was published in 1993 and so, admittedly, its stats from 1988 were newer then and probably have changed some since then, and vary considerably. But, because we are discussing this paper specifically, let's go with it.

Halloween is a major party opportunity for students. It is also an opportunity to dress in costume. This study took a look at the behavior of college students and the role that Halloween costumes play in whether students masquerade with a group and if these factors relate to alcohol and drug use. Why should wearing a costume make such a difference? Well, it has to do both with the relationship between dress behavior and self as well as the disguise of identity.

The study looked at a total of 1,253 students from two colleges in upstate New York and included both sexes across all age ranges and class years. A questionnaire called "Halloween Activities" was administered to the students to gauge their Halloween partying practices. The questionnaire revealed dressing in costume to be associated with alcohol use, in fact, 85% of those who partied on Halloween used alcohol. There was no relationship between wearing a costume and drug use, though. They asked students if they used costumes to hide or disguise their identity and related that to alcohol use, and they found no significant association. On the topic of "masquerading with a group" they found an association between drugs and groups, but of those who used these substances a greater number did not masquerade with a group.

The study advises educators to "emphasize that dressing in costume can be a positive social experience - one that allows for creative expression of the self - and that alcohol and other drugs are not necessary to enhance this experience," that students could dress "for both fun and fantasy when wearing a costume."

Here's the paper:
Miller, Kimberly A., Cynthia R. Jasper, and Donald R. Hill (1993) Dressing in costume and the use of alcohol, marijuana, and other drugs by college students. Adolescence: Spring 1993; 28(109), 189-198. (PMID: 8456608)

It's Alive!

Happy Halloween! The next couple of posts are going to be Halloween inspired. This first one was sent to me by a friend, and I'm going to quote most of it to keep it simple. It is a story about the science that inspired Mary Shelley to write Frankenstein.

"Written in 1818, the book was influenced by a scientific feud that ushered in the first battery and our modern understanding of electricity.

The story begins in the mid-18th century. Electricity had captured the imaginations of many of Europe's top scientists, and at that time very little was understood about the nature of electricity. Scientists could generate static electricity using spinning machines, but it was not until Benjamin Franklin's famous kite experiment in 1752 that they proved that lightning was of the same essence.

At the Univ. of Bologna in Italy, noted surgeon Luigi Galvani was investigating the effects of electricity on animals. It was not an unusual line of inquiry. Researchers knew electrical shocks produced violent spasms and speculated that electricity might cause muscular contractions.

On January 26, 1781, while dissecting a frog near a static electricity machine, Galvani's assistant touched a scalpel to a nerve in its leg, and the frog's leg jumped. Galvani repeated this and several other experiments, observing the same violent muscle spasms. He also noticed that frog legs occasionally twitched when they were hung from a brass hook and allowed to touch an iron trellis, so Galvani joined a length of each metal together to form a brass and iron arc that made the leg muscles contract when touched.

But where did the electricity come from?
Galvani, who called it 'animal electricity,' believed it resided in the frog itself. He thought that the bimetallic arc merely conducted the electricity from one part of the frog to the nerve, causing the leg to jump. He published his findings in 1791 and, as the story goes, came to be known as the frog dancing master.

One of Galvin's earliest readers was Italian physicist Alessandro Volta. Volta already had earned an imposing reputation as the discoverer of electrical capacitance, potential, and charge, and also discovered and was the first to isolate methane gas. He replicated Galvani's experiments and helped popularize his work.

Yet Volta reached very different conclusions. He believed the electricity came from the two metals used in the arc, and that the frog was acting as the conductor. Within the year, he replaced the frog's leg with brine-soaked paper, detected a current, and challenged Galvani.

The scientific world divided into two camps, animal electricity versus dissimilar metals. The feud became bitter. At one point, Volta wrote to a friend that his opponents wanted him dead. 'I'll be damned if I'll oblige them,' he added.

In 1799, Volta invented the voltaic pile, a stack of discs of two different metals separated by brine soaked paper. The galvanic or voltaic cell was the world's first battery, and the progenitor of automotive lead-acid batteries.

Today, we know that Volta's stack worked because dissimilar metals transferred electrons in an oxidation-reduction reaction, and the frog legs moved because electricity plays a role in muscular contractions. Of course it would take many decades to work out the details to reach this level of understanding.

So how did this influence a young Mary Shelly and lead her to compose one of the most widely read novels of all time, 'Frankenstein; or, The Modern Prometheus'?

Galvani's nephew, Giovanni Aldini, was a fierce partisan of animal electricity, yet he did not ignore Volta's pile. Aldini used it to tour the capitals of Europe and demonstrate the medical benefits of electricity -- or not. His demonstrations involved jolting corpses with electricity and making decapitated criminals sit upright.

Aldini's most famous exhibition took place in 1803 at the Newgate Prison in London, U.K. He inserted metal rods into the mouth and ear of the recently executed corpse of murderer George Foster. 'The Newgate Calendar,' a book about the criminals of Newgate Prison, described what happened next: 'On the first application of the process to the face, the jaws of the deceased criminal began to quiver, and the adjoining muscles were horribly contorted, and one eye was actually opened. In the subsequent part of the process the right hand was raised and clenched, and the legs and thighs were set in motion.'

Not surprisingly, some observers thought Aldini was bringing Foster back to life.

Mary Shelley knew all about Galvani, Volta and Aldini. Humphry Davy and William Nicholson -- the era's leading electrical researchers -- were friends of her father. In 1816, at age 19, she spent the summer in Geneva, Switzerland with Lord Byron and her future husband, Percy Shelley. The season was cold and rainy, and they spent many evenings around the fire, reading German ghost stories and discussing electricity's potential to reanimate corpses.

It must have seemed like she was merely peering into the near future to imagine that one day, a Victor Frankenstein might succeed in reanimating an assembly of body parts."

You can see the actual story I quoted here:
http://www.laboratoryequipment.com/News-the-science-behind-frankenstein-102910.aspx

Because of Halloween and the popularity of Frankenstein, this story has been making its way around the Internet. And, granted, has been appearing verbatim on many credible news sources and websites. But I usually try to verify a story before posting it, if I can. This one, however, was a bit more difficult to track down. I did find some interesting information posted by Sherry Ginn of Wingate University on a University of Florida website. The information there seems to support the above story, as do some other sources, and so I'm pretty confident that it is authentic. You can read that entry and more about Mary Shelley's life here :

http://www.clas.ufl.edu/ipsa/2003/ginn.html
And here is some additional info about Mary Shelley and the writting of her book:
http://www.independent.co.uk/arts-entertainment/books/reviews/the-original-frankenstein-by-mary-shelley-with-percy-shelley-ed-charles-e-robinson-1017483.html

Know Your Nerds

Threadless is a tee shirt website that has an ongoing open call for tee shirt design submissions. Here is a great one that was posted on to how know the different types of nerds. Excellent.

http://www.threadless.com/product/2538/Know_Your_Nerds

Feel Useful

This is a really creative ad that I think you'll enjoy:

On the Spot

Have you ever looked at a leopard and wondered why it has spots and not stripes or why it is patterned and not plain? A new study in the Proceedings of the Royal Society B looks at just that question.

The patterns themselves come in a large variety even within the wild cats, and previous studies have suggested that they are for camouflage in these predominantly ambush predators. It is known that hunts are more successful when an attack is initiated from shorter distances. Makes sense. And smaller cats are probably camouflaged for both a hunting advantage and protection from predators. Other studies have also found spots to be significantly associated with arboreality (the presence of trees or a forest or movement within the trees) with dark spots, in particular, associated with closed habitats and predators that prey on ungulates (hooved animals). The conclusions about stripes have been a little less than clear.

The researchers collected images of 35 species of Felidae from the Internet from various wildlife photography resources. They then picked 6 of the best images from each species, images where the animal was shown in profile, full view, free of distortions and occlusions, in focus, in dry weather, and in natural lighting. Then they took rectangular crops of the images using the base of the neck and tail. They then had to classify the images according to the type of pattern they were seeing.

So how do you go about measuring the influence of spots? I mean, consider the jaguar vs. the clouded leopard vs. the serval. All of them have spots, but none of them have the same kinds of spots. So in order to study the evolution of pattern you need to come up with a better way than just calling something spotted. The method used in this study was inspired by reaction–diffusion theories of biological pattern formation. I'm not so much up on those kinds of theories, but here is how the paper describes it:

"Human observers classified standard examples of felid flank patterns to the closest matching comparison pattern in this multidimensional space. The values of variables in the underlying equation that generated the chosen pattern and distribution of observers' classification decisions parameterize the important properties of each standard image. The five dimensions can be conceptualized as: (i) patterned versus plain, (ii) pattern irregularity, (iii) pattern complexity, (iv) pattern element size and (v) the anisotropy (directionality) of pattern elements."

One the measures were characterized they were tested against ecological variables that have been proposed to drive the evolution of pattern phenotypes. These variables include habitat, locomotion, activity time, social systems, prey size, body size, and weight.

After lots of images and lots and lots of stats what did they find? Basically that flank patterns function as camouflage. Okay, not really a new finding, just the same finding with a different method (but the more support for a hypothesis the better right?). They also found that evolution has generally paired plain (unpatterned) cats with relatively uniformly colored, textured, and illuminated environments. Patterned cats were paired with environments that are "full of trees and bushes and stripy, speckly, patchy-blatchy shadows." It is likely that the pattern on the cat resembles the background pattern of the habitat in which it lives or hunts. The cat species living in closed environments and who move around in the trees are more likely to have complex patterns than those who live in open environments and move around on the ground. Felids that have especially irregular patterns live in tropical areas and tend to be nocturnal hunters, preferring to hunt in the trees.

On the topic of stripes, as with previous studies, these authors found no evidence to support the proposition that vertical stripes are associated with grasslands. Considering that the tiger was the only one to be classified as having vertical stripes and its favored habitat is not a grassland, that seems pretty plausible to me.

It wouldn't be a scientific study if you didn't have some outliers to speculate upon. For example, the cheetah (Acinonyx jubatus). This cat has a pattern and yet lives and hunts in a grassland/savanna habitat. Similar outliers include servals (Caracal serval) and black-footed cats (Felis nigripes). On the other side of the coin there are those species who have plain coats but live in closed environments, such as the bay cat (Pardofelis badia) and flat-headed cat (Prionailurus planiceps). Its possible that these outliers could be utilizing different microhabitats within the categories used by this study. Perhaps plain and patterned cats have instances in which the (non-)pattern works and some where it doesn't. Or maybe they are constrained genetically or developmentally. Its difficult to say.

Here's the paper:
Allen, William L., Innes C. Cuthill, Nicholas E. Scott-Samuel and Roland Baddeley (2010) Why the leopard got its spots: relating pattern development to ecology in felids. Proceedings of the Royal Society B: published online. ( DOI: 10.1098/rspb.2010.1734)

If you want to take a look at some of these cats and here patterns then look here:
http://www.zooinstitutes.com/Zoology/family.asp?name=Felidae

And here are some story links:
http://www.bris.ac.uk/news/2010/7264.html
http://www.sciencedaily.com/releases/2010/10/101019212914.htm

(image from webshots.com)

I Wear a Coat

We were talking in the lab today about Lonely Island's I'm on a Boat and all the parody's that had been made. I mentioned the I'm in a Pond post from a while back and a labmate told me about I Wear a Coat, a med school parody.

The Evolution of the Geek

I ran across this handy infographic from FlowTown. It chronicles the evolution of the Geek. Click on the image to see a full resulution of the image on FlowTown.

Its What's For Dinner

The tyrannosaurids belong to a group of carnivorous dinosaurs called theropods within the Saurischia ("reptile-hipped") dinosaurs. They lived during the Cretaceous, 85-65 million years ago. They are characterized by massive skulls with short but deep jaws containing large sharp teeth, elongate hindlimbs, small eyes, and highly reduced forelimbs. The Tyrannosauridae taxon includes such creatures as Albertosaurus, Gorgosaurus, Daspletosaurus, Tarbosaurus, and of course Tyrannosaurus rex. These were the dominant large carnivores during the Late Cretaceous in North America and Asia. The T. rex is the last and largest of the terrestrial carnivores. Their fossils are actually relatively common in North America, particularly their teeth. These teeth, with their large banana shape, leave recongnizable markes on the bones of other dinosaurs. You would think that this would make it easy to piece together the feeding habits of these dinosaurs, but it is still difficult to even broadly classify the animal as predator, scavenger, or both. We all grew up thinking of T. rex as a mighty hunter, but the evidence against the predator hypothesis includes the animal's small eyes (most predators have large eyes to help find and follow prey), small arms (difficult to hold struggling prey with dainty little forearms), and large legs (seem fast but are actually slow). Add to it the fact that there is evidence of T. rex teeth scoring bone but not actually killing the prey, bones have healed. Scavaging, however, uses all of these traits as a plus and includes supporting evidence such as large olfactory lobes (smelling foul, dead meat well helps you find it). However, if you look at extant, large predators they are opportunists, scavanging when it is available, and if you look at animals such as birds, sharks, and snakes you will notice that little arms aren't that much of a disadvantage. See how there is some confusion?

In a study published in PLoS ONE this week, palentologists discuss a different type of T. rex feeding habit. During a study of Maastrichtian (latest age of the Late Cretaceous) dinosaurs one of the researchers found a large theropod pedal phalanx (foot/toe bones) that had tooth marks on it that were made by a large carnivorous dinosaur. Considering the geographic region (North America) and the time period, T. rex was the only large carnivore known and so a very likely candidate for inflicting the bone damage. They examined this bone as well as other dinosaur specimens. They found a total of 17 specimens bearing tooth marks made by Tyrannosaurus. The deep U- and V-shaped gouges and shallower scores resemble those found on the pelvis of a Triceratops, and closely resemble the furrowed ‘puncture and pull’ traces that have previously been attributed to T. rex. Four of the examined specimens represent Tyrannosaurus. That's right, we're talking cannabalistic Tyrannosaurus rex!

Figure 2. Tyrannosaurus rex bones bearing
 tooth marks made by Tyrannosaurus rex.

The authors argue that the marks on the bones are the result of feeding rather than fighting. They say that the traces would be difficult to inflict on a live animal, and that, in the case of one bone, the marks are the result of two or three bites. Considering that most animals probably wouldn't sit still while a Tyrannosaur repeatedly bit them, that seems likely. Additional evidence includes where the bites occurred - on the toes (tightly bound in life and not the targets during a fight) rather than the vulnerable head or flanks. Finally, there is no bone remodeling (healing) evidenced, suggesting that the animal died.

Put this together and it gives more evidence to the hypothesis that Tyrannosaurus was an indiscriminate, opportunistic feeder. It didn't just go for herbivorous dinosaurs but also other Tyrannosaurs. The bone marks found in this study were probably the result of scavenging. However, you can't rule out that the Tyrannosaur killed its prey and fed on it over a long period of time.

Cannibalistic Tyrannosaurs, whew, that's a visual right? But, if you think about it, cannibalism isn't all that uncommon in nature. I mean, its been seen in bears, alligators, hyenas, etc. So it seems a good arguement for T. rex as well.

Very cool.

Read more in the paper (its free access):
Longrich Nicholas R., Horner John R, Erickson Gregory M., and Currie Philip J. (2010) Cannibalism in Tyrannosaurus rex. PLoS ONE: 5(10), e13419. (DOI: 10.1371/journal.pone.0013419)

Thesis Insanity



Piled Higher and Deeper

A friend sent me a great webpage called The Five Stages of Grading, which rings so true that it is funny. That reminded me of a little stress-relieving thing I put together while writing my thesis. I call it "Thesis Insanity."

"Significant advances in the understanding and treatment of graduate students in the midst of thesis writing has brought greater recognition to the field of science over the past few decades. The writing of a thesis is a process that results in all different types of mental disorders, including disorders of thought, mood or behavior. These disorders cause distress and result in a reduced ability to function psychologically, socially, occupationally or interpersonally. People that are in this writing process might have trouble handling such things as daily activities, family responsibilities, relationships, or social responsibilities. They can have trouble with one area or all of them, to a greater or lesser degree. And they can have more than one type of these responses at the same time. The symptoms a person experiences and the clinical features that accompany this process are used to identify and classify this disorder. As time goes by and we gain a clearer understanding of how specific genes interact with writers block or other specific behaviors, a much more sophisticated classification system may be developed that is directly linked to a biologic cause, rather than just symptoms. Some disorders with similar symptoms and clinical features, such as the patterns and processes involved in doing research, are very different in terms of their underlying biology. To treat them similarly simply because they share the same symptoms may not be appropriate. Does writer’s block have a biological basis — a problem with the brain's chemistry? Not always. Many serious writer’s block situations do have a strong biological basis but that's not the entire story. Some people, for example, might have an inherited, biological tendency to completely skip over large chunks of pertinent information. They can experience serious revision anxiety even though no specific event triggers it. Others, however, have no known inherited tendency for these exclusions. But if something happens, such as a new publication in a top journal, it can trigger major reorganization. It is not yet known if the underlying neurochemical aspects of these reactions are the same. In other words, one person may have writer’s block because of their nature — their genetic vulnerabilities, their neurochemical functioning. And another person may have a writer’s block because of nurture — a research environment based cause that perhaps then alters their neurochemistry. Most of the time, however, it's probably a complex interaction of both nature and nurture. Manuscript submission might be all that some people need to restore their brain chemistry to a more normal state. But for others, manuscript submission, although effective, doesn't alter the way they cope with the stress that might have contributed to their illness. Graduation and employment can help change coping behaviors and offer strategies to help understand and modify risk factors associated with this disorder. Very often, a combination of graduation and employment is most effective."

Flashy Fins

Figure 1: X-ray image of Pelvicachromis taeniatus

If you recall the Fish-stache story then you will also recall that I explained sexual selection in this way:

"When it comes to sexual selection in the animal world, it is the usually the sex that puts more effort (and has more to lose) into the results that gets to be the choosy sex. Usually this means females get to be picky. After all, eggs are more expensive than sperm and females often end up contributing quite a bit with parental care. This choosiness means that males need to impress females through the evolution of secondary sexual traits. This could be, and usually is, just about anything: elaborate feathers, complicated dances or mating calls, gift giving, etc."

So what happens when you see a highly developed ornament on a female of a species? Usually such ornaments are seen as non-adaptive, they are simply the genetic correlations of male ornaments. But, if you go back to the who "gets to be the choosy sex" argument and apply it to females you may find that females are looking to attract males that give them something that they need in addition to a sperm contribution. Perhaps the male takes care of the female (or "invests in female quality"), or maybe he contributes a significant amount of parental investment (or he's a good baby-daddy). This idea of females evolving ornaments to attract males has gained some ground recently. And that topic is today's article.

There is a species of cichlid fish called Pelvicachromis taeniatus where both sexes have ornamentation. This fish is known to be biparental and socially monogamous. Both sexes develop large, colored pelvic fins that they present to their potential mates during courtship. The pelvic fin of female fish is exceedingly large and differs from the male fin in both color and shape (it is triangular rather than thread-shaped). During courtship, females spread out their violet, triangular pelvic fin and fan it at the males. This behavior enlarges "their violet ventral nuptial projection area," suggesting that the fin and behavior are used to attract males. This study took a look at the allometric relationship of the pelvic fin compared to other fins (anal, caudal, dorsal, and pectoral fin), and then tested male preferences for females showing larger or smaller pelvic fins to determine the effect of fin size on male mate choice.

I would be remiss and probably confuse the heck out of you if I didn't take a sentence, or a few, to explain allometry. The most basic of basic definitions is that allometry is the relationship between size and shape. You define the dimensions of a body part (or trait or character) in relation to the body size, with the scale relating trait size to body size. What you get is an allometric relationship, and these are typically classified in three ways:
(1) Isometry - the ratio of trait to body size is constant
(2) Negative Allometry - large individuals have small traits
(3) Positive Allometry - large individuals have relatively larger traits
This relationship is driven by evolutionary constraints, natural selection, and/or sexual selection. And when you look at those traits driven by sexual selection you usually see option (3) Positive Allometry. Although a positive allometry does not mean the trait was driven by sexual selection.

In the experiment, the researchers took X-ray images of the females so they could analyze trait and body size. Then they conducted mate choice experiments to see which female characters the males preferred. Typically this is achieved by putting a female fish in one tank and a male fish in an adjacent tank and observing the courtship or lack of. Then the trait of interest can be altered (fin clipping, etc) or a substitute used. In this case the researchers used computer animations of females with various pelvic fin sizes. The use of the computer allowed them to standardize the stimuli and eliminate many confounding variables.

The allometry study found that the female pelvic and caudal fins showed isometry in relation to body size, but the anal, dorsal, and pectoral fins showed negative allometry. The females showed a constant ratio of pelvic or caudal fin size to body size, but the other fins were relatively smaller in larger females. They also found that the size of the pelvic and caudal fin is more positively related to body size than the other fins, suggesting that these fins are under selective pressures that the other fins are not. Remember when I said that sexually selected traits usually show positive allometry? This study showed isometry and negative allometry, no positive. The authors hypothesize that when you incorporate viability selection you end up with a more complex relationship between body size and traits, that natural selection and sexual selection "could have synergistic effects on the evolution of traits, thus sexually selected traits may be scaled into isometry or even negative allometry." Perhaps the amount of variation in traits under directional sexual selection may be limited by natural selection, that natural selection is constraining the pelvic fin size of these fish. Basically, a gigantic fin attracts a mate but slows you down and makes it easier for predators to get you. So you find a middle ground, a fin that isn't too big and gets you eaten but isn't too small so that you never attract a mate. This scaling down for the predators is where the isometry and negative allometry are showing themselves.

The mate choice experiment showed that males like large pelvic fins. But why? Could be that the large fin is an indicator to female quality. These indicators may be direct (fertility, fecundity, or maternal investment) or indirect (genetic benefits, parasite resistance, pretty daughters). Translated - If she can carry around that big fin and survive then she must have good behaviors and genes. The researchers found pelvic fin size in females to be positively related to body condition. So it is likely that the indicators are reliable. I haven't discussed much about the violet color of the female pelvic fin, but the fins are colored similar to the ventral violet nuptial belly coloration. The size of this ventral coloration is associated with female quality, indicating the fecundity of the female, her readiness to spawn, and may reveal information about her maternal quality and offspring survival rates. Again, all indicators that tell the male that she's quite a catch (no pun intended).

Anyone who has spent time with a group of females (of any species) knows that there's some competition going on, and you can't rule that out in a study such as this. These cichlid fish show sequential aggressive behaviors towards other females. Before a fight escalates a female will present and fan out her pelvic fin to show off her body condition and body size in the hopes of intimidating and driving off the rival female.

When it comes to fish studies, especially sexual selection studies, there are many. This study is unique in that it is the first to show that male choice might scale the allometry of a female sexual trait. This is important in understanding the scaling relationship of female traits with body size and starting to tease out the selection pressures driving the evolution of these ornaments.

Read the study here:
Baldauf, Sebastian A., et al. (2010) Male mate choice scales female ornament allometry in a cichlid fish. BMC Evolutionary Biology: 10, 301. (DOI: 10.1186/1471-2148-10-301)

The Buzz on the Bees

I was flipping through (or rather, scrolling through) a few popular news sites and noticed that a recent paper published in PLoS ONE has gained some traction. It is a story about honey bees and Colony Collapse Disorder.

The European honey bee (Apis mellifera) is a common pollinator worldwide. You can find them where there are flowers to feed on and suitable hive-building sites. Most of the individuals you see buzzing around your garden collecting pollen are females (workers), the males are significantly bigger and are very few in number. These social insects heat their hives with body heat and cool it by fanning their wings, this way they can live year-round in a place surviving on their honey reserves through the winter.

As you may have guessed by their common name, these honey bees are not native to the western hemisphere. They were brought over by early European colonists for their honey and wax production. Over time, beekeepers have experimented with the about two dozen subspecies, but they've found that Apis mellifera ligustica (a subspecies brought over by early Spanish settlers) is favorable.

Beginning in October 2006, beekeepers started reporting the losses of 30-90% of their hives. Some loss is normal, but this amount is highly unusual. Colony Collapse Disorder (CCD) is the name that has been given to this serious, mysterious die-off of honey bee colonies across the U.S. CCD is characterized by sudden colony death with a lack of adult bees in front of the die-outs. Honey stores and recent brood rearing are often evidenced, and sometimes the queen and a small number of survivor bees remain. Although there have been published incidences of honey bee disappearances - in the 1880's, 1920's, and 1960's - it is unclear if this same phenomena has happened before. Descriptions are similar to CCD but as it is yet unknown what causes CCD it is difficult to tell.

This year, 2010, CCD has once again devastated honey bee colonies in the US, at rates that are potentially higher than the occurrence in 2006-2007. Previous scientific studies, using sensitive genome-based methods, have found small RNA bee viruses and the microsporidia, Nosema apis and N. ceranae in healthy and collapsing colonies alike. However, no single pathogen has been linked to hive losses.

The study published this week in PLoS ONE used mass spectrometry-based proteomics (MSP) to identify and compare proteins from healthy and collapsing honey bee colonies. This particular method revealed two previously unreported RNA viruses, Varroa destructor-1 virus (VDV-1) and Kakugo virus. They also identified an invertebrate iridescent virus (IIV) (Iridoviridae), a DNA virus, and linked it to the CCD colonies. The CCD colonies were found to not only contain  IIV but also Nosema (specifically N. ceranae). The IIV, in particular, is interesting because it was thought until now that small RNA viruses were the cause of bee diseases. The pairing of IIV and N. ceranae and their correlation with CCD colonies suggests that they track each other and they do not occur concurrently in healthy colonies. Laboratory cage trials add more evidence to support this hypothesis.

It is hypothesized that damage to the bees' gut epithelial tissue and other host cells by N. ceranae allows entry to IIV. Or, perhaps, the replication of N. ceranae in honey bee cells may decrease the bees' ability to ward off viral infections. The presence of IIV may prove to be a useful tool in identifying colonies in the early stage of CCD or a possible resistance to the virus in a strong colony. IIV's are not completely unstudied. In fact, a good amount of study has been done on them for use as biopesticides. IIV-3 and IIV-6 have had a complete genome sequencing, and 24 other IIV's have been partially characterized. Viral diseases are currently only manageable rather than curable, with infected bee populations needing culling. Nosema, however, is treatable with current management techniques. Since their pairing suggests increased lethality, disrupting the relationship may be an option to help reduce bee mortality.

You can read the paper here:
Bromenshenk, Jerry J., et al. (2010) Iridovirus and Microsporidian Linked to Honey Bee Colony Decline. PLoS ONE: 5(10): e13181. (DOI: 10.1371/journal.pone.0013181)

Also, here's a NY Times article on the subject:
http://www.nytimes.com/2010/10/07/science/07bees.html

Also, check out these links for more information on Colony Collapse Disorder:
Mid-Atlantic Apiculture Research and Extension Consortium (MAAREC)
United States Department of Agriculture: Agricultural Resource Service
United States Department of Agriculture: National Agricultural Library
The Ohio State University's Agriculture Network Information Center's Bees and Pollination Page

(image from nycgovparks.org)

Colour Canon

I was scrolling through the blog today and noticed that recently most of the posts have been videos rather than articles. I blame that entirely on all the field work that I've been doing recently. Measuring trees all day really just makes me want to shower, eat, and sleep (in that order) when I get home. But, well, excuses excuses right? All that said, I'm going to post another video.

This one is a bit techie, and a commercial (kinda), but its cool enough that I had to post it. The last minute, especially, is pretty sweet.


Canon Pixma: Bringing colour to life from Dentsu London on Vimeo.

I'll Show You My Pipette

A sciency parody of Flight of the Conchords "The Most Beautiful Girl in the Room." What do you do with your conical tubes?

Yo Chuck!

2009 marked the bi-centennial of the birth of Charles Darwin. At the Shrewsbury Folk Festival in rural Shropshire, England the Darwin Song Project was organized. Eight of the top folk artists from the US and the UK - Chris Wood, Karine Polwart, Mark Erelli, Rachael McShane, Jez Lowe, Stu Hanna, Krista Detor and Emily Smith - came together for a week to write songs about the life of Darwin. There was a concert premiere on March 19, 2009 in Theatre Severn, Shrewsbury and it was recorded for a live CD release. Here's one of their songs and you can buy it and find more at their website (http://www.darwinsongproject.com/). Enjoy!

Beer and Wiesn



'Tis the season of beer. Last week I went over to an Oktoberfest event to celebrate with some sweet treats and bitter libations. The fact that there was a German band singing American cover songs in German just made it all that much more enjoyable. So I decided to type the search term "oktoberfest" into both PubMed and Web of Science to see what popped up. The first return was something dealing with the pancreas -- nah. The second, however, was just the kind of thing I was looking for.

Web of Science returned an article from the Archives of Toxicology titled "Munich Oktoberfest experience: remarkable impact of sex and age in ethanol intoxication." Bingo!

Oktoberfest traditionally starts in the third weekend in September and ends the first Sunday of October. So today is the last day to celebrate, make it a good one. According to Munich's Oktoberfest History Page, when Crown Prince Ludwig (later King Ludwig I) married Princess Therese of Saxony-Hildburghausen on October 12, 1810 the citizens of Munich were invited to attend the festivities. These festivities were held on the fields in front of the city gates, fields that were later renamed Theresienwiese, or "Theres'a Fields," (now just called "Wiesn") to honor the princess. The royal family attended horse races at the close of the event, and the decision to repeat the races annually gave rise to the tradition of Oktoberfest. In subsequent years other attractions and activities were added such as an agricultural show, carosels and swings, and beer stands. Today Oktoberfest is the largest celebration in the world!

According to the article, approximately 6 million individuals visited Oktoberfest in Munich in 2004. About 5,000 of these individuals had to undergo medical treatment for various reasons. Intoxication, as you probably surmised, is one of the biggest concerns when a patient seeks medical attention. This study took a look at the large number of individuals suffering from alcohol intoxication with the goal to identify risk factors and optimize patient management.

The researchers collected data on 405 intoxicated individuals (with no other trauma or complications). Such data included age, gender, and a medical examination. The Glasgow Coma Score (GCS) was used both at check-in and check-out to assess level of consciousness. Then patients received an intravenous (IV) infusion of either 500 ml Ringer-Lactate solution (a fluid and electrolyte replenisher) or 10% glucose solution depending on the results of a blood glucose test. Then blood pressure (mean, systolic, and diastolic), heart rate, body temperature, respiratory rate, blood glucose, oxygen saturation, and acid-base balance were monitored.

The results showed that the higher the GCS level the more likely the patient was to be hospitalized. Not all that surprising since the higher the GCS the lower the consciousness. They also found a that men have a strongly increased risk of hospitalization when compared to women. Age was also a factor with individuals between 20-29 years old having a higher risk than all other age groups. The researchers called these results surprising, but, well, I've been in enough bars to call them rather unrevealing.

However, there was one point in their paper that I found rather interesting. Although the 20-29 male age group were found to be at the highest risk they actually showed lower blood ethanol concentrations when compared to men aged 30-39 years and 40-49 years. The 20-29 year old men's blood ethanol concentratrions also did not differ significantly from that of 20-29 year old women. Why? Its hard to say. The researchers were unable to exclude higher biological susceptibility to alcohol toxicity from their study, although this particular age group is known for their "general robustness" (*snigger*). The authors conclude that "a plausible explanation might be that young individuals, especially young men, tend to ignore their individual critical limits of ethanol intoxication. Peer pressure and lack of experience may be responsible for this behaviour." I probably didn't need a scientific study to tell me that.

Here's the paper:
Binner, C., et al. (2008) Munich Oktoberfest experience: remarkable impact of sex and age in ethanol intoxication. Archives of Toxicology: 82, 933-939. (DOI: 10.1007/s00204-008-0373-z)

Hope you had a great Oktoberfest!

(image from holdmybeer.com)