Author Archives: Bora Zivkovic

Clock News

Different strokes occur at different times

Different types of strokes occur most often at different times of day say scientists at Iwate Medical University in Iwate, Japan.
The team based their findings on data from 12,957 cases of first-ever stroke diagnosed by CT or MRI scans and drawn from the Iwate Stroke Registry between 1991 and 1996.The researchers chose patients who had experienced cerebral infarctions, or ischemic strokes, where cells die because blood flow to the brain is restricted, and two kinds of hemorrhagic strokes: intercerebral hemorrhages that occur within the brain, and subarachnoid hemorrhages that occur in arteries at the brain’s surface.
The wake-sleep cycle (circadian rhythm) was divided into 12 two-hour intervals. All three types of stroke had peaks between 6 and 8 in the morning and 6 and 8 in the evening with fewer incidents during sleep when blood pressure is the lowest. But cerebral infarctions had a higher peak in the morning and a lower peak in the afternoon and the two hemorrhagic strokes had a higher peak in the afternoon and a lower peak in the morning.

Update: There is more information on this page.

Birds!

I And The Bird #30 is up on Burning Silo. Get your birding blogging thirst quenched today!

Pluto and other characters from Duckburg

If you go to the ScienceBlogs front page you will see that The Buzz word of the day is Pluto. And when there is a new Buzz Word, a lot of us tend to post about it – see how many already chimed in on the topic.
I am actually quite happy to see the revisions of the definition of a planet. The old 9-planet system was just too neat and clear-cut, too iconic, to fixed and unmovable.
Let’s jolt the masses out of the lull and show them the way science moves and changes and shatters our most valued beliefs!
Twelve planets today, twelve thousand planets tomorrow, twelve million planets in OUR OWN Solar system in a century? Why not? That would redefine what a “solar system” is and replace simplicity with complexity which, IMHO, is a good thing for everyone to learn to deal with.
For more information, John McKay provides the history and Phil Plait gives the scientific details.

Another case of Evo-Psych abuse…

Have you heard about the stupid German study that uses evo-psych Just-So-Stories about, supposedly, women losing interest in sex shortly after marriage?
I wanted to dissect it when it first came out but Real Life and time-constraints prevented me. In the meantime, Dr.Petra, Shakespeare’s Sister, Amanda and Echidne ably debunked and destroyed the study and the media reporting on it, so I don’t have to do anything but link to them.

Cracks in the Wall, Part III: Escape Ladders

The third part of the series on authoritarian psychology by Sara Robinson is now up on Orcinus. It tackles the strategies for dealing with (and hopefully healing and converting) the victims of authoritarian upbringing who turned out authoritarian themselves. The whole series is a must-read.

Woomers are Back to The Woom

KateWD: Eggplants and Exploitation
Mr.WD: Talkin’ Tut: ‘magic’ and ‘Africans’

Carnival of the Liberals #19: The Parody Poetry Edition

New Carnival of the Liberals is up on One Flew East.

Carnivals – science, history, education and being in graduate school

Tangled Bank #60 is up on FrinkTank.
History Carnival XXXVII is up on Mode For Caleb.
Carnival of Education #80 is up on Education Wonks.
The first Carnival of GRADual Progress is up on Fumbling Towards Geekdom.

Downloadable Database of Phase Response Curves

Downloadable Database of Phase Response CurvesThis April 16, 2005 post gives you links to further online resources and literature on entrainment and Phase-Response Curves, as well as a link to a database of PRCs so you can play with them yourself.

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Clock Tutorial #14: Interpreting The Phase Response Curve

Clock Tutorial #14:  Interpreting The Phase Response CurveThis is the sixth post in a series about mechanism of entrainment, running all day today on this blog. In order to understand the content of this post, you need to read the previous five installments. The original of this post was firt written on April 12, 2005.

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Clock Tutorial #13: Using The Phase Response Curve

Clock Tutorial #13:  Using The Phase Response CurveThis is the fifth post in a series about mechanism of entrainment. Orignally written on April 11, 2005.

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Clock Tutorial #12: Constructing the Phase Response Curve

Clock Tutorial #12:  Constructing the Phase Response CurveThe fourth post in the series on entrainment, originally written on April 10, 2005, explains the step-by-step method of constructing a PRC.

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Clock Tutorial #11: Phase-Shifting Effects Of Light

Clock Tutorial #11: Phase-Shifting Effects Of LightThe third post in the series on entrainment, first written on April 10, 2005, starts slowly to get into the meat of things…As always, clicking on the spider-clock icon will take you to the site of the original post.

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Clock Tutorial #10: Entrainment

Clock Tutorial #10: EntrainmentThis is the second in a series of posts on the analysis of entrainment, originally written on April 10, 2005.

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Clock Tutorial #6: To Entrain Or Not To Entrain, That Is The Question

 Clock Tutorial #6: To Entrain Or Not To Entrain, That Is The QuestionThis post from February 03, 2005 covers the basic concepts and terms on entrainment.

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Blog-post as a scientific reference

TITLEThe post coming immediately after this is, as far as I know, the only blog post so far that appeared in the List Of References of a scientific paper.
A guideline for analyzing circadian wheel-running behavior in rodents under different lighting conditions by Corinne Jud, Isabelle Schmutz, Gabriele Hampp, Henrik Oster and Urs Albrecht is an excellent article on methodology (and reasoning behind it) of basic circadian research. It was published in an online open-source journal Biological Procedures Online. I strongly recommend it to my readers.
The Reference #16 is to this post on Circadiana. Coming up on this blog in one hour!

Obligatory Reading of the Day – Academic Blogging

Fred Stuzman: Blogging: Academia’s Digital Divide?:

Considering the value my blog has added to my academic experience, I tend to believe that academic blogs will eventually mainstream. Their acceptance will take some time, but the value provided by blogging – in terms of connecting with others, the public debate, the real dialogue that emerges – will be self-evident. Of course, some things will never change – being a good blogger will always take effort, and not all of us need to blog. However, as we see models develop for academic blogging, it stands that more and more of us will want to take advantage of the benefits.

While science blogging has some specifics that make it different from social science/liberal arts part of the campus, Fred’s notes are quite applicable to us as well.

I don’t mean to NAAG you, but….

Jenna has been nagged by NAAG recently, to the point of obsession. It is also one of the molecules I included in the Synapse puzzle.
So, if you want to learn a little bit of nitty-gritty detailed neurochemistry of this exciting (as of recently) neuromodulator (and possibly neurotransmitter), you should check her two-part post reviewing what is known about it: Part I and Part II.

Carnivals

The Scian Melt is up on Nonoscience.
New carnival of Homeschooling is up on The Common Room.

Bring back the mammoth, or, not so fast!

Archy is on top of the story, as usual when the story is about people trying to resurrect mammoths!

Does circadian clock regulate clutch-size in birds? A question of appropriatness of the model animal.

Blogging on Peer-Reviewed Research

 Does circadian clock regulate clutch-size in birds? A question of appropriatness of the model animal.This post from March 27, 2006 starts with some of my old research and poses a new hypothesis.

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Quail: How many clocks?

Blogging on Peer-Reviewed Research

One of the assumptions in the study of circadian organization is that, at the level of molecules and cells, all vertebrate (and perhaps all animal) clocks work in roughly the same way. The diversity of circadian properties is understood to be a higher-level property of interacting multicelular and multi-organ circadian systems: how the clocks receive environmental information, how the multiple pacemakers communicate and synchronize with each other, how they convey the temporal information to the peripheral clocks in all the other cells in the body, and how perpheral clocks generate observable rhythms in biochemistry, physiology and behavior.

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Persistence In Perfusion

Blogging on Peer-Reviewed Research

Persistence In PerfusionThis post, from January 25, 2006, describes part of the Doctoral work of my lab-buddy Chris.

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How eyes talk to each other?

Blogging on Peer-Reviewed Research

One of the important questions in the study of circadian organization is the way multiple clocks in the body communicate with each other in order to produce unified rhythmic output.

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Quick Break from All-Clock Blogging for some news…

Go say Hello to the newest addition to the Seed ScienceBlogs stable, The Scientific Indian.
Grand Rounds 2.46 are up on Hospital Impact. My readers will probably appreciate the entry on sleep disorders by rdoctor.

Clock Tutorial #9: Circadian Organization In Japanese Quail

Circadian Organization In Japanese QuailGoing into more and more detail, here is a February 11, 2005 post about the current knowledge about the circadian organization in my favourite animal – the Japanese quail.

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Clock Tutorial #8: Circadian Organization In Non-Mammalian Vertebrates

Blogging on Peer-Reviewed Research

Circadian Organization In Non-Mammalian Vertebrates This post was originally written on February 11, 2005. Moving from relatively simple mammalian model to more complex systems.

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Clock Tutorial #7: Circadian Organization in Mammals

Blogging on Peer-Reviewed Research

Circadian Organization in Mammals This February 06, 2005 post describes the basic elements of the circadian system in mammals.

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ClockTutorial #5: Circadian Organization

ClockTutorial #5: Circadian Organization
I wrote this post back on February 02, 2005 in order to drive home the point that the circadian clock is not a single organ, but an organ system comprised of all cells in the body linked in a hierarchical manner:

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All Clocks All Week

As I announced last week, this week will be All Clocks All The Time. Why?
First, I need to move some of the old posts from Circadiana over here, at a faster rate than I’ve been doing so far. Second, I’ll be quite busy this week. Third, I need to hype myself up for the final effort at my Dissertation so blogging about any other topic would be counter-productive (not that it’s not gonna happen…)
So, here is the deal. Over the next five days I will repost some old and write some new posts on three big topics in Chronobiology: circadian organization, entrainment and photoperiodism. Within each topic, I will start with posts that are basic and general and gradually move towards more and more detailed, or specific, or up-to-date posts (what students call “hard material”), ending with descriptions of some of my own (published only) work in those areas.
Perhaps you should prepare for this by checking out some of the Clock Tutorials that I have already re-posted here. I have started by defining the field in What Is Chronobiology, followed by a post that serves as a dictionary reference to Basic Concepts and Terms.
I have tackled the questions of the origin, evolution and adaptive function of biological clocks twice, from two different angles, in Clock Evolution and Whence Clocks.
You can read about the early history of the field, from the early days until about 1960s, and with heavy emphasis on Darwin’s own work, in Darwin On Time. I followed up the history to a more modern time, and connected it to what we know about clocks, in Forty-Five Years of Pittendrigh’s Empirical Generalizations. Even more recent history, focusing on the molecular findings, you can read about in Clock Genetics – A Short History.
Finally, in order to understand the findings in the field, you need to know how the experiments are designed and why – this tells you about the way chronobiologists think. So, check out On Methodology.
Then, you’ll be ready for this week in clocks.
On Monday (that is, later today), we’ll start tackling Circadian Organization. What are the elements of the circadian system, where are they in the body, how they work, how they get the information from the environment, how they communicate with each other, and how they generate observable, measurable rhythms – those are the questions covered in this section.
I’ll start with a post tackling the general question about circadian organization (longer than the previous sentence). Then, I’ll focus on circadian organization in mammals mainly because it is comparatively simple and serves as a good reference point for comparison to clock systems in other organisms. I’ll only cover the basics, leaving much of complexity and recent findings aside for now. Then, I’ll move to non-mammalian vertebrates and their complicated circadian organization, with emphasis on birds (because we know the most about them). Finally, I’ll get down to nitty-gritty detail in a post about circadian organization in a single species – the Japanese quail, the lab animal model I did all my work on.
On Tuesday, I’ll follow up with one or two posts about the Doctoral research on circadian organization in Japanese quail done by my lab-mate Chris: how the two clocks in two eyes manage to always stay in sync with each other? I will follow that with one or two posts on my own Masters work on retinal and extra-retinal pacemakers and photoreceptors in quail and the question if the (female) quail organization is reducible to one complex circadian system or can be best understood as two separate systems that communicate with each other.
On Wednesday, we move on to Entrainment, with a series of six posts explaining what entrainment is and how it is studied – a tutorial on very simplified physics of (coupled) oscillators, which sounds hard but if you go slowly you will “get it”, I hope.
On Thursday, you will see two posts on the timing of seasonality and photoperiodism – something that depends on the understanding of entrainment from the previous day. Then, I intend to write about some of my own work that combined a study of entrainment with a study of photoperiodism.
Finally, on Friday, I’ll try to put it all together with one new and one old post about the circadian control of body temperature – from physiology and behavior to ecology and evolution, with a tangential look at entrainment by scheduled feedings and the phenomenon of “masking”.
I hope you enjoy this five-day mini-course and find it useful and enlightening. I appreciate all feedback on how to make those posts clearer, more readable and more useful to casual blog-readers and students alike.

An Important Ethical Question

Should Scientific Research be conducted on prisoners?

PGR v.1n.9

Pediatric Grand Rounds Vol.1, No.9, is now up on Unintelligent Design. You have to do a quiz. Multiple choice only.

Plan B Prevents Abortion!

First, go to Well-timed Period and Pharyngula to get all the neccessary information about Plan B, what it is, what it isn’t, and how it works. Then go to Bitch PhD and buy a T-shirt (for which you need to know what you are talking about because you WILL be asked).

Do you write about trees? Have you ever tried? Should you?

You have until August 29th to write a post about trees, or a particular tree, or a picture of a really cool tree, or a poem about a tree…and send it to Burning Silo for the next edition of the Festival of the Trees

The real Heathrow story….

Shakes has the quickest, clearest summary (with good additional links) about what happened at Heathrow last week, how media lied to you yet again, and who picked the timing and why. I hear that my cousin was at Heathrow at the time and ended up flying four hours too late, but I have not heard from him directly to get any jiucy tidbits.

Obligatory Readings of the Day – more on Conservatives…

In Jeebus can’t see through the walls of the Ramada, Amanda adds some excellent commentary on my guest-post over on Echidne.
I know I have already linked to Cracks In The Wall, Part I: Defining the Authoritarian Personality yesterday, but here it is again if you missed it, especially now that Cracks In The Wall, Part II: Listening to the Leavers is also up. Very worth reading.

Tar Heel Tavern

Tar Heel Tavern #77 is up on Another Blue Puzzle Piece. The theme is “the future is now” and it creatively done.

Obligatory Readings of the Day

Sara Robinson on Orcinus: Cracks In The Wall, Part I: Defining the Authoritarian Personality
Amanda: Sometimes a cigar is just an arbitrary social custom and You might not be trailer trash if you think Jeff Foxworthy is funny
Lance Mannion: A joy forever
Publius: POLITICIZE TERRORISM
Mr. WD: Violence and Beauty
Tekanji on Alas, A Blog: Modesty and raunch culture: two sides of the same sex-negative coin and Ampersand on the same spot: Beyond Marriage
Berube: Leftover business V
Neil: You’re Invited to Our Party! Bring Friends!

It treats spider bites!

Woman Finds ‘God’s Water’ Gurgling in Tree and 33% of AOL readers agree that it is God’s water, with another 28% not sure!

Tar Heel Tavern – call for submissions

Next Tar Heel Tavern will be hosted tonight (Saturday) by etbnc (one of my most frequent commenters) on My Blue Puzzle Piece. The theme is “the future”:

That can include predictions, prescriptions, hopes, dreams, near future, far future, middlin’ future, back to…etc.

Send your entries to: tht70 AT nc DOT rr DOT com

Friday Weird Sex Blogging – The Giant Stinkin’ Phallus!

Well, this Friday Weird Sex Blogging is not going to be so unique. After all, Janet and Zuzu have already blogged about it, but who can resist a phallic-looking, rotten-meat smelling, fly-attracting flower! And it is not a B-grade movie on the sci-fi channel. This is real! The Titan Arum (Amorphophallus titanum), in all its 3m tall glory is about to start stinking up the greenhouse at the Brooklyn Botanical Garden (follow the flowering on the blog or watch the flowering web-cam here) :

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No One Cares About Your Blog

I guess the people at Belk only read personal diaries and Wingnut blogs. They should come visit Scienceblogs sometimes.
no%20one%20cares%20about%20your%20blog.jpg
(hat-tip:Ed)

Eye Color

Carel discovered a fascinating website about iris pigmentation. As Carel notes:

Morgan Worthy, a retired psychologist, has put together an iris pigmentation site that includes lists of iris color for over 5,600 vertebrate species, along with observations based on his database that range from the insightful to the mundane to the crackpottish.

There are hypotheses there concerning eye color in humans and in animal predators. Looks like a treasure trove of material for blogging when you are out of inspiration and especially if you are wondering what to send next for the Skeptic’s Circle.

Mananimals in the news again

Not just in the USA. Visceral queeziness coupled with religious sentiment coupled with scientific ignorance appears in other parts of the world as well, as in the UK

The Scottish Council on Human Bioethics, a professional group based in Edinburgh, has published a report on the ethical implications of the practice in the journal Human Reproduction and Genetic Ethics. The report is online at www.schb.org.uk.

The article lists some examples of research:

Later research has spawned human-animal creations, the report said. These usually die at the embryonic stage, but often survive if the mixtures involve only a few cells or genes transferred from one species to another.
The council cited the following examples:
* In 2003, scientists at Cambridge University, U.K. conducted experiments involving fusing the nucleus of a human cell into frog eggs. The stated aim was to produce rejuvenated master cells that could be grown into replacement tissues for treating disease. It was not clear whether fertilization took place, but some kind of development was initiated, the report said.
* In 2005, U.K. scientists transplanted a human chromosome into mouse embryos. The newly born mice carried copies of the chromosome and were able to pass it on to their own young.
* The company Advanced Cell Technologies was reported, in 1999, to have created the first human embryo clone by inserting a human cell nucleus into a cow s egg stripped of chromosomes. The result was an embryo that developed and divided for 12 days before being destroyed.
* Panayiotis Zavos, the operator of a U.S. fertility laboratory, reported in 2003 that he had created around 200 cow-human hybrid embryos that lived for about two weeks and grew to several hundred cells in size, beyond the stage at which cells showed the first signs of developing into tissues and organs.
* In 2003, Hui Zhen Sheng of Shanghai Second Medical University, China, announced that rabbit-human embryos had been created by fusing human cells with rabbit eggs stripped of their chromosomes. The embryos developed to the approximately 100-cell stage that forms after about four days of development.

All of this sounds like useful basic science to me.

Such procedures mix human and animal biological elements to such an extent that it questions the very concept of being entirely human, the report said. This raises grave and complex ethical difficulties.

So? Learn to deal with it. It won’t apply for a passport any time soon.

Some ethicists worry that the experiments might force society to make confounding decisions on whether, say, a human-chimp mix would have human rights. Other concerns are that such a creature could suffer from being outcast as a monster, from having a chimp as its biological father or mother, or from unusual health problems.

That was a quick leap from clumps of cells with mixed genes or cells to walking, talking human-chimp chimeras which, as far as I can tell, no scientists are considering of ever making, except mad scientists in cartoons.

Some inter-species mixtures are powerful research tools, the report said.
This became clear about a decade ago in a series of dramatic experiments in which small sections of brains from developing quails were taken and transplanted into the developing brains of chickens. The resulting chickens exhibited vocal trills and head bobs unique to quails, proving that the transplanted parts of the brain contained the neural circuitry for quail calls. It also offered astonishing proof that complex behaviours could be transferred across species.

Those were realy cool experiments by Evan Balaban, but have nothing to do with mananimals. Those are not genetic chimaeras. Those are surgically transplanted tissues, like you and I getting a pig heart if needed.

While there is revulsion in some quarters that such creations appear to blur the distinction between animals and humans, it could be argued that they are less human than, and therefore pose fewer ethical problems for research than fully human embryos, the committee wrote.

What? What anthropocentric essentialism! And of course, the image accompanying the article is supposed to make you all squeamish:
humandog.JPG
Why didn’t they put this picture instead?
centaur.jpg

ConvergeSouth 2006

The second ConvergeSouth conference on blogging and journalism will be held on the NC A&T University in Greensboro, NC on Saturday, October 14, 2006. Check out the homepage and blog and register soon. It is going to be even more of an Unconference than last year.
Although it is expected that many in attendance will be from the vibrant local blogging community, it is by no means restricted to the South. Last year, we had people coming in from California, New England and abroad, so if you are interested in the blogging/podcasting world, this is a place to be.
I have blogged about the last year’s ConvergeSouth, both as a whole and specific sessions, which you can check out here, here, here, here, here, here, here, here, here, here and here.
If you have any questions, or want to propose a topic for a session, contact Sue or Ed as they are the people “in the know” there.
Technorati Tag: ConvergeSouth

AIDS at 25

Seed ScienceBlogs are liveblogging the 16th International AIDS Conference in Toronto from August 13th-18th.
Two special correspondents on the ground, and our own Tara Smith of Aetiology will post daily commentary on a blog specially dsigned for this occasion – AIDS at 25.
Quite fittingly, the AskTheScienceBlogger question of the week is also about AIDS, and I am sure that a number of my SciBlings will write about the topic in addition to just answering the question, so you will have plenty of opportunity to be informed and educated about AIDS over the next several days. And, if you have not done this yet, this may be a good time to make Scienceblogs.com one of your Technorati favourites.

My picks from ScienceDaily

Teens Who Do Use Condoms Often Don’t Use Them Properly:

A worrying number of young people who do use condoms don’t use them correctly, so risking unwanted pregnancy or infections, reveals research published ahead of print in the journal Sexually Transmitted Infections. But a good relationship with their mothers seemed to be associated with correct condom use, the research showed.

Paleontologist Discovers South American Mammal Fossils:

Fossils of a new hoofed mammal that resembles a cross between a dog and a hare which once roamed the Andes Mountains in southern Bolivia around 13 million years ago was discovered by Darin A. Croft, assistant professor of anatomy at the Case Western Reserve University School of Medicine and a research associate at the Cleveland Museum of Natural History.

Pressure To Be More Muscular May Lead Men To Unhealthy Behaviors:

New research suggests that men feel pressure to have muscular bodies, and that influence can lead some to symptoms of eating disorders, pressure to use steroids, and an unhealthy preoccupation with weightlifting.
—————–snip—————-
“Instead of seeing a decrease in objectification of women in society, there has just been an increase in the objectification of men. And you can see that in the media today,” she said.

Light Guides Flight Of Migratory Birds:

Songbirds use multiple sources of directional cues to guide their seasonal migrations, including the Sun, star patterns, the earth’s magnetic field, and sky polarized light patterns. To avoid navigational errors as cue availability changes with time of day and weather conditions, these “compass” systems must be calibrated to a common reference. Experiments over the last 30 years have failed to resolve the fundamental question of how migratory birds integrate multiple sources of directional information into a coherent navigational system.
Last autumn, Rachel Muheim, a postdoctoral associate in biology professor John Phillips’ lab at Virginia Tech, captured Savannah sparrows in the Yukon before they headed south. She was able to demonstrate that the birds calibrate their magnetic compass based on polarized light patterns at sunset and sunrise.
———————snip———————–
Polarized light is light that oscillates in one plane relative to the direction of propagation. At sunrise and sunset, there is a band of intense polarized light 90 degrees from the sun that passes directly overhead through the zenith and intersects the horizon 90 degrees to the right and left of the sun. Just as the sun location changes with latitude and the time of year, so does the alignment of the band of polarized light.
Muheim and Phillips argue that migratory songbirds average the sunrise and sunset intersections of the polarization band with the horizon to find the north-south meridian (geographic north-south axis), providing a reference that is independent of time of year and latitude. The birds then use this geographic reference to calibrate their other compass systems.
In other words, polarized light, the Sun and stars, and the geomagnetic field are all directional cues for migration, but polarized light appears to provide the primary reference system used to calibrate the other compass systems, said Phillips.
However, previous research had suggested a much more confusing picture.
Migratory birds are born with an innate magnetic compass preference that coincides with their species’ migratory direction. Previous research suggested that before the migration period, songbirds are able to recalibrate the magnetic compass when exposed to a “conflict” between magnetic and celestial (including polarized light) cues, but during migration it appeared that the reverse was true, — the magnetic field was used as the primary reference for calibrating the birds’ other compass systems. But in a few experiments with birds during migration, the birds did recalibrate the magnetic compass.
When Muheim and Phillips did a literature review, they noticed a difference between the experiments of the few scientists who saw migratory birds recalibrate their compass and of those whose birds failed to recalibrate.
“It is important how you do the experiments. It turns out that the part of the sky that matters is just above the horizon,” said Phillips. “In cue conflict experiments carried out before migration, birds were usually housed in outdoor aviaries in a rotated magnetic field, where they had a view of the whole sky, including the horizon. Once migration starts, however, scientists usually exposed birds in “funnel cages”. This is so, after exposure to the cue conflict, the birds’ directional preferences could be recorded; songbirds in migratory condition leave tracks or scratches on the sides of the funnel as they attempt to take flight in the migratory direction. A problem arises, however, because funnels block the lower 20 degrees of the sky. In the only two experiments (out of 30 or so) carried out during migration where birds were exposed to the cue conflict with a view of the horizon, they did recalibrate their magnetic compass — just as was previously observed only in experiments carried out prior to migration.”
Muheim’s experiments proved that seeing polarized light cues near the horizon was the critical factor. “Once the right hypothesis came along, it all fit,” said Phillips.

History of the University

There are several excellent book reviews in the latest American Scientist. Check them out for reviews of Dennett and Collins books, if nothing else, but the one that caught my eye was the review of Academic Charisma and the Origins of the Research University by William Clark, which I will, just because of this review, put on my Amazon wish list. It is a history of academia and how it got to be organized the way it does today.

Rethinking the Fall of Easter Island

An interesting article in the new issue of the American Scientist, challenges the view, made popular by Jared Diamond in Collapse, among others, of the collapse of Easter Island civilization due to overpopulation and cutting down of trees:

“Easter Island has become a case study of human-induced environmental disaster, or “ecocide.” The popular narrative, most famously recounted in Jared Diamond’s book Collapse, depicts native inhabitants triggering the fall of their once-flourishing civilization by cutting down all of the island’s trees. But recent archaeological and paleoenvironmental research point to a very different story. The island may not have been settled until around 1200 A.D., centuries later than previously thought, and it may have been a large rat population, not the human inhabitants, that caused widespread deforestation. This evidence sheds new light on a story that has long fascinated outsiders.”

Say Hi To The New SciBling

The most recent addition to the stable of Seed ScienceBloggers is Molecule Of The Day – better living through chemistry! Go say Hello!