Mouse with human brain speaks out

In the previous post, I described the one known mouse with a human brain. He’s named Clyven, and you can talk to him on the website of the hospital where research led to his creation. Or go direct to his page, here.

Well, imagine my surprise when Clyven himself posted a comment on that post. He was, as usual, brief and to the point:

Clyven's comment.jpg

Of course I rang Clyven up, and found him unengaged and ready to talk. He did not seem to remember our previous conversation but when I raised the subject of Christine O’Donnell, he became more animated. Here’s that portion of the brief interview:

ME: Clyven, I’d like to hear what you have to say about Ms. O’Donnell.
CLYVEN: I’m ever so pleased Christine O’Donnell spoke about me on the O’Reilly Factor back in 2007.
ME: What do you think of what she said?
CLYVEN: Aspiring Senator O’Donnell could perhaps learn a thing or two from a mouse with human cognition.
ME: And Christine O’Donnell as a person, how did she strike you?
CLYVEN: She’s funny. I think she is a witch!
ME: What are your political principles, Clyven?
CLYVEN: You should check out the main RYT Hospital web site for that: RYTHospital.com.
ME: A very politic answer, Clyven! Thank you for talking to us.

Clyven is a mouse of few words, which makes those few even more important. His gratitude for Ms. O’Donnell’s mentioning him on O’Reilly’s show may indicate that he would like to play a part on a wider stage himself. He is a native-born American, of American parents, but his crucial role in advanced biomedical research may rule out a run for office. A panel discussion, perhaps, with the two Delaware senatorial candidates? I can only hope that those whose job it is to plan such events and bring new points of view to the public, will be contacting him as soon as they’ve read this post.

O’Reilly, are you listening?

Human germ attacks already declining coral reefs

Plague, rabies, Lyme disease, bird flu and swine flu—people seem much more at risk for diseases from animals than the other way around. But it does go the other way too, and it has been discovered that such a case is responsible for a disease that has devastated coral reefs in the Caribbean.

“White pox disease” in coral is caused by a human strain of the common intestinal bacterium Serratia marcescens, which causes the hospital infection serratiosis. (Hospital infections, or nosocomial infections, happen because individuals already in poor health are exposed to pathogens by poor sanitary practices and invasive procedures such as surgery or catheterization.) [Etymological notes on scientific names are at the end of the post.]

The only coral known to be affected is Elkhorn coral (Acropora palmata), a major reef-bulding species in the Caribbean. Healthy Elkhorn coral looks like this.

Healthy Elkhorn coral (Acropora palmata).jpg

Here’s an example of Elkhorn coral infected with White pox disease.

White Pox Disease (Serratia marcescens) on Elkhorn Coral.jpg

A research team at the University of Georgia was recently awarded a $5M grant to investigate the disease in coral, which is “the first known case of such a ‘reverse zoonosis’ that involves the transmission of a human pathogen to a marine invertebrate”. Even more remarkable, in the words of James W. Porter, associate dean of the Odum School of Ecology and the team’s leader, “This bacterium has jumped from vertebrate to invertebrate, from terrestrial to marine, and from anaerobic to aerobic environments. Triple jumps like this are rare.”

In addition, according to the report in ProMED (partly drawn from this source),

The scope of the team’s research will extend beyond gaining an
understanding of the impact of white pox disease on elkhorn coral and
how to counter it. The most likely source of the pathogen for coral
reefs is under-treated human sewage, so the study will also explore
the intersection of public health practices and environmental health
outcomes.

“This investigation addresses not only environmental protection, but
also the socio-ecological determinants of coastal zone protection,”
said Porter. “This includes the cost of wastewater treatment
infrastructure. Given a reliance on tourism by most Caribbean
countries, this study addresses a disease system that is of great
economic importance and public health concern to developing nations.”

“This is science in action to save an endangered species and a threatened ecosystem,” said team leader Porter. “We are linking good public health practices to effective environmental protection.”

Elkhorn and Staghorn coral (Acroporis cervicornis) are both on the US Federal list of threatened species, and in 2008 the National Oceanic and Atmospheric Administration extended additional protection rules usually reserved for endangered species. The new rule will “prohibit the importing, exporting and taking of elkhorn and staghorn corals. Additionally, the rule prohibits any activities that result in the corals’ mortality or injury. Anchoring, grounding a vessel or dragging gear on the species is prohibited. Additionally, damaging the species’ habitat and discharging any pollutant or contaminant that harms the species violates NOAA’s new rule. The rule applies to elkhorn and staghorn coral in the Virgin Islands, Puerto Rico and Florida.” Of course the enforcement will be difficult, but it appears that it’s none too soon to reverse the decline of these reef-building species.

A recent analysis of 500 surveys of 200 reefs showed the most complex types of reef had been virtually wiped out across the entire Caribbean. What survives are mostly “flattened” reefs which provide poor habitat for fish including commercial species, and are less “effective in protecting coastal homes and villages from storm swells and tidal surges”.

Healthy reef of staghorn coral in the Caribbean, below.

Healthy Staghorn coral (Acropora cervicornis).jpg

Source.

When the branched corals are killed off, low-growing corals may take their place but don’t create the rich three-dimensional habitat that the branched ones do. Algae also may increase and blanket surfaces, preventing coral growth.

Flattened coral reef, degraded by loss of branching coral).jpg

Source. Photo by Jennifer E. Smith.

Other threats to coral reefs

Coral-building animals live symbiotically with algae. Influenced by water that is too warm or cold, the corals will “expel the algae (zooxanthellae) living in their tissues causing the coral to turn completely white. This is called coral bleaching. When a coral bleaches, it is not dead. Corals can survive a bleaching event, but they are under more stress and are subject to mortality.” Rising ocean temperatures have caused wide-spread bleaching events. Warm waters also absorb more CO2, causing the water to become more acidic and that makes it more difficult for reef-building organisms to form the calcium carbon skeletons that serve as their structural basis.

Overfishing, pollution including sewage and agricultural runoff, dredging,hurricanes, and development have all damaged coral reefs. Each new injury reduces the ability of living organisms to reproduce and to withstand further assaults.

Coral reefs are among the world’s richest ecosystems, second only to tropical rain forests in plant and animal diversity. They arfe essential to fisheries, tourism, and protecting beaches from erosion. Yet “nearly two-thirds of the Caribbean’s coral reefs are threatened by human activities. Agricultural runoff, overfishing, dredging, sewage discharge (a factor in White pox disease), and the growing pace of coastal development have already degraded important reef systems, resulting not only in a tremendous loss of biodiversity but also lost revenue from declining tourism and fishing, and increased coastal erosion.” This last statement comes from the World Resources Institute, which is active many environmental fronts and is currently sponsoring a country-by-country survey of the economic values of Caribbean coral reefs and mangroves: “Supporting the sustainable management of coral reefs and mangroves by quantifying their economic value”.

Elkhorn coral & research robot.jpg

Source. Some breakage from hurricanes can be seen. Also shown is Fetch1, an autonomous underwater vehicle for research that was developed by NASA.

More about coral reefs

Global Coral Reef Alliance
EPA, Coral Reefs and your Coastal Watershed
University of Florida, Overview with photos

Etymological notes

Serratia marcescens was discovered in 1819 by Venetian pharmacist Bartolomeo Bizio, as the cause of an episode of blood-red discoloration of polenta in the city of Padua.[7] Bizio named the organism four years later in honor of Serafino Serrati, a physicist who developed an early steamboat; the epithet marcescens (Latin for “decaying”) was chosen because of the pigment’s rapid deterioration. [Wikipedia]

Acropora palmata: Acropora from the Greek, akros (high) and poros (opening, pore); palmata handlike, from Greek palma (a palm, flat hand; palm branch).

Acropora cervicornis: Acropora as above; cervicornis from the Latin cervus (deer) and cornu (horn, antler)

Christine O’Donnell, religion, and the human brain

Poor would-be senator Christine O’Donnell has been ridiculed for her comment about mice with human brains:

O’DONNELL: … these groups admitted that the report that said, “Hey, yay, we cloned a monkey. Now we’re using this to start cloning humans.” We have to keep…

O’REILLY: Let them admit anything they want. But they won’t do that here in the United States unless all craziness is going on.

O’DONNELL: They are — they are doing that here in the United States. American scientific companies are cross-breeding humans and animals and coming up with mice with fully functioning human brains. So they’re already into this experiment.

From transcript of O’Reilly show, Friday, November 16, 2007.

Why would Ms. O’Donnell (or someone who informed her) believe this?

Reports of mouse-brain research have been greatly exaggerated

It doesn’t take much to find some of the “evidence” that may have convinced her or her informant. As others have noted, there have been experiments in which human cells were injected into embryo mice, and became part of their brains. A bit different than “cross-breeding humans and animals and coming up with mice with fully functioning human brains”, but all rumors have to start somewhere.

Bad reporting may be to blame: here’s the headline and first line of the 2005 article on the National Geographic site:

NatGeo article on mice.jpg

From nationalgeographic.com.

In case that last line is too small to read, it says “Researchers in California have created living mice with functioning human stem cells in their brains.”

Earlier that same year (2005) another article on the NatGeo site briefly referred to the same research (before it had occurred) this way “And at Stanford University in California an experiment might be done later this year to create mice with human brains.” The title of this misleading article was Animal-Human Hybrids Spark Controversy. Yes, plenty of controversy, but in the article no hybridization is being talked about, only the use of stem cells to demonstrate their potential to be re-purposed. In biology, a hybrid is the offspring of two plants or animals of different species or varieties, such as a mule (a hybrid of a donkey and a horse), and that is the popular understanding as well. Few would consider a mouse with a few cells of human origin, all functioning as mouse cells, to be a hybrid.

mouse with human headSM.jpg

Christine, you need a smart friend; meet Clyven the mouse

But wait, it’s not all down to irresponsible journalism; perhaps Ms. O’Donnell got her information from this page, on the site of the prestigious RYT Hospital, about “Clyven: The World’s First Transgenic Mouse with Human Intelligence” :

Clyven1.jpg

Here’s the explanatory text from that page.

Margaret A. Keyes, M.D., Ph.D., is a researcher in genetic medicine and Professor of Cell Biology and Genetics at RYT Hospital-Dwayne Medical Center. She is exploring the use of embryonic stem cells as a means to cure neurological conditions such as Alzheimer’s Disease and Creutzfeldt-Jakob Disease.

By implanting human brain cells (grown from a human embryo’s stem cells) into a mouse engineered to have Alzheimer’s, Dr. Keyes inadvertently made a remarkable and startling discovery: she not only cured the mouse’s Alzheimer’s Disease, but the animal soon developed the relative intelligence of a human being.

After extensive consideration by RYT Hospital’s Institutional Review Board (IRB) and Institutional Animal Care and Use Committee (IACUC), it was decided that this mouse would be placed under a new study led by Dr. Keyes’ lab.

As part of this new facility (pictured to the right), Clyven is placed inside a light-sensitive box with electrodes attached to him. He is able to communicate and interact with people via this neuro interface. He is able to communicate and interact with people via this neuro interface. [sic] To hear a live audio feed of Clyven inside his box, please click here.

© RYT Hospital-Dwayne Medical Center
Source.

Evidently RYT Hospital has a very understanding Ethics Committee; they approve of confining an animal with a human brain in a little box and punching his head full of electrodes. But Clyven is not bored—in fact, you are invited to chat with him or play a game against him.

Chat with Clyven.jpg

Unfortunately, Clyven’s conversation is limited and repetitious—maybe he himself wrote that quoted passage above, that has the repeated sentence. My best conversation with him was this one,

ME: Hi Clyven.
MOUSE: Yo.
ME: Do you know that a tea party candidate is talking about you?
MOUSE: That’s pretty silly.
ME: Yes.
MOUSE: Tell me more.
ME: I don’t want you to know how dumb people can get.
MOUSE: I’m sorry. I hope to get smarter as time goes on. Please be patient with me. I will be receiving additional neurological treatments next week.

On the other hand, don’t let him persuade you to bet money on that CheezeMaze contest, he’ll beat you paws down.

It’s surprising we haven’t heard more about this RYT Hospital, with the amazingly advanced and useful research that is being done there. Elsewhere on the site, you can read about a new drug, Revitalex

Revitalex.jpg

about successful gene therapy for back pain, and about “NanoDocs”, nanobots that circulate throughout the body repairing tissues.

medical nanites.jpg

Okay, so it’s not a real site but the project of an artist named Virgil Wong. He’s a painter, film-maker, and head of web design for two real hospitals.

Still, can’t you see how anybody might be taken in by the slick style, and accept that there really is a mouse with human intelligence, and nanobots that can tidy up your blood vessels?

No? You say anyone beyond the stage of believing in the Tooth Fairy should have seen through this? and through the distorted reports of growing human brains in mice?

I think so too.

Wherever Christine O’Donnell may have gotten her “information” about mice with human brains, the real problem is minds like hers that are unprepared to question things that most of us would find outlandish. They also believe that Obama is Hitler, Stalin, and a Kenyan anti-colonialist, all at the same time! which would explain why, as I have heard on good authority, Obama has three heads, a fact cleverly concealed by camera angles and good tailoring.

Newt, Eastern.jpg

Eastern Newt (Notophthalmus viridescens), Red Eft Stage. Etymological note: Notophthalamus from the Greek noto (a mark) and ophthalmus (eye), presumably in reference to the eye spots on the sides and back; viridescens from the Latin, (slightly green) referring to the greenish color of the adults. Source.

One born every minute? or are they made?

Where do these credulous people come from? I don’t mean people like Newt Gingrich, who will repeat anything—no matter how preposterous—if it seems advantageous. No, demagogues use untruths consciously, with calculated intent. The power of the demagogue depends upon there being enough people who cannot distinguish between the likely, the possible, and the absurd, and therefore won’t laugh him off his soapbox. And where do they come from?

The beginning preparation for most credulous people of otherwise normal intelligence is, I think, being raised with a huge area of life and thought which is categorically excluded from rational examination. Now, every culture and sub-culture has some areas like that, because they are essential as part of the group’s self-definition. In this Land of the Unquestioned reside things like appropriate behavior (manners), kinship rules, dress codes, what we eat and how we cook it, all that sort of thing. That’s why our way of life seems so logical and natural, and other groups’ ways seem bizarre and senseless.

No problem when it’s a question of the relative merits of haggis or corn on the cob, but in the area of exclusion there are more significant topics also, such as attitudes to the “Other” (women, outsiders, those in your own group who don’t conform), and toward violence. That’s the cultural “Don’t think about these things” list. Then there’s religion and its list.

Religion is the really big no-fly zone for human reason. It covers a much wider area of life than ordinary cultural indoctrination, often upon a foundation of dogmatic zeal which asserts sole possession of truth, and enforces details of the dogma with extreme fervor.

Totalitarianism and extremist religions share two fundamental principles: there is only one true way, and everyone must be forced to acknowledge it. It is not enough for the non-believer to refrain from critical expression and deviant action: he or she must be made to believe. Hence the show trials held by the Soviets, the Chinese Cultural Revolution, and the Inquisition, in which tortured inmates confess their nonexistent sins; hence the death penalty for apostasy in Islam, and the roasting alive of unrepentant Christians by the Romans and doggedly heathen Native Americans by the Christians. The Other must be brought within the fold or die, and it should be done in a public and painful way to present a compelling example to everyone else.

Children are born enquirers (non-believers), and about the age of three they start to ask “Why?” about everything, with irritating persistence. Give an answer and they ask for more details or ask “Why?” again. (Offer a non-answer like “I don’t know” or “Be quiet” and they repeat the original question or say nothing; curiosity discouraged begins to shut down.) Their brains are making and pruning connexions, they’re constructing an internal model of the world, and they want and need to know more and to discuss their own thoughts. They are also learning how to learn, how to figure things out.

A child who gets yelled at for asking about talking snakes, or smacked for asking why the God of Love is such a bloody-handed war-approving tyrant in the Old Testament (see note 1), will learn to accept what he or she is told and not think about it. The lesson is to avoid questioning—especially the things in life that seem illogical, cruel, unfair, out of sync with reality. And that “respect for authority” (actually, it is only respect for power and avoidance of punishment) carries over into other parts of life. The more intensely the “No Questions Zone” is defended, the more timid the young mind’s reason becomes.

Curiosity is inborn, but logic is learned. When children are exposed to illogical conclusions, such as “You got a cold right after you ate that ice cream, so no more ice cream” or “I know the Bible is the Word of God because the preacher says so and the Bible says to follow what the preacher says” they won’t learn the basic rules of logic that help humans sort true from false, as well as “probably true” from “probably false”. Ignorance of logic is of course a good thing for those enforcing a monolithic belief system.

Our country’s culture has an equivocal position on learning. Along with its tradition of independence and individualism, the US also has a strong anti-intellectual tradition, because of its religious foundations and the pragmatic demands of survival on successive frontiers from New England to the Pacific coast. When book-larnin’ is seen as irrelevant, perhaps un-masculine, some will make a positive virtue of ignorance. Also, study is hard, ignorance is effortless. Entropy prevails.

Logic and critical thinking are not enough. In order to winnow the wheat from the chaff reliably, it’s necessary to have some actual knowledge. When a statement is made, the hearers check it against their relevant knowledge base. This process is usually instant and automatic. The new information may directly conflict with existing knowledge, or it may just appear quite unlikely based on what is already known. A certain stock of knowledge, reliable because it has been tested or was provided by a trusted authority, is needed to get through life. Yet even some of this knowledge may be false—blondes are dumb, bankers are trustworthy, a barking dog never bites—and individuals must also possess the willingness to re-examine beliefs based on new experience. Except in the No Thinking Zone, where the only safe course is to agree with authority and otherwise keep your mouth shut.

When politics is the subject, then history must have special prominence among relevant areas of knowledge. Just like more workaday fields of endeavor, political systems embody responses to real needs and problems. If I were re-designing the internal combustion engine, I would first need to know why each part had been designed as it was; what earlier mechanisms were tried for mixing the fuel or timing the ignition, and what were their flaws?

It is history which answers these questions in politics, and must be consulted before tinkering or throwing away parts. For example, decades of controversy about the constitutional provision in the First Amendment usually referred to as “separation of church and state” have distorted public understanding of the law’s intent by framing it as a dispute between agnostics or atheists, vs. religious people. In fact it was enacted to defend all religions from government, and from a preference being shown for a single church, as well as to protect government (or non-religious persons) from religion. And the history of state-established religions illustrates the many repressions and disenfranchisements which are imposed upon members of the non-official religions, even including banishment and death. Only modern ignorance permits the discussion of this subject to be framed entirely as a conflict between religion and irreligion. [Christine O’Donnell, in a recent debate, was ignorant of the provision entirely. After the phrase “Government shall make no law respecting establishment of religion” was quoted to her, she asked “That is in the First Amendment?” Yes, it is, though the exact words are “Congress shall make no…”.]

Logic, general knowledge, critical thinking, history: how is the American public doing on these?

37% of Americans believe that houses can be haunted, and 25% believe in astrology, i.e. that the position of the stars and planets can affect people’s lives.

Fewer than a third can identify DNA as a key to heredity, only about 10% know what radiation is, and 20% think the Sun revolves around the Earth, an idea science abandoned by the 17th century.

50% of our fellow citizens believe in alien abductions, though happily only 7% say they or someone they know has been abducted.

39% of Americans could not name any of the freedoms in the First Amendment.

14 percent of Americans say President Barack Obama may be the Antichrist (24 percent of Republicans believe this). Almost 20% believe he is a Muslim. Does that add up to 34% or is there some overlap?

Two-thirds of 1,000 American adults polled couldn’t name a single current justice of the Supreme Court. In the same survey, more than a third did not know the century in which the American Revolution took place, and half of respondents believed that either the Civil War, the Emancipation Proclamation or the War of 1812 occurred before the American Revolution.

And 21% believe in witchcraft, so O’Donnell’s “I’m not a witch” ad did have its audience.

When you look through these and other poll results it seems that at least 10% to 25% of Americans believe in just about any unproven concept you can imagine. A larger percentage is very ignorant of history and public affairs.

If you’re reading this, and have been apathetic about getting to the polls, you better think again.

One final poll result: in 2009, 19% percent of Americans agreed that the First Amendment goes too far in the rights it guarantees, and 39% said the press has too much freedom.

mr natural.jpg

≈≈≈≈≈≈≈≈≈≈≈≈≈≈

NOTE 1: I cite only two examples, both from the same holy book, for the sake of brevity, but every religion seems to have its own set of magical events and unquestioned cruelties which must be accepted in order to belong. Belong, get along, go along.

Western Tiger Swallowtail butterfly, and a very close look at butterfly wing-color

We’ve gotten a few terrific photos of butterflies this year—some posted here and here— but none of the swallowtails has cooperated by alighting within range. When I saw one that had died and fallen to the road I carefully carried it home for the chance to get a close look.

Papilio 02 Dorsal.jpg

There are at least three very similar species of swallowtail around here—the Anise, Western Tiger, and Oregon Swallowtails. Based on the red and blue markings I’m thinking this is the Western Tiger Swallowtail, Papilio rutulus.

Finer than “frog hair”—butterfly hair!

Enlarging the macro photos shows details such as hairs on the body and along the inner edges of the wings.

Papilio40 CLOSE 1.jpg

These hairs, called tactile setae, are attached to nerve cells, which relay information about the hairs’ movement to the butterfly. … Adults have tactile setae on almost all of their body parts. In both adults and larvae [caterpillars], the setae play an important role in helping the butterfly sense the relative position of many body parts (e.g., where is the second segment of the thorax in relation to the third segment). This is especially important for flight, and there are several collections of specialized setae and nerves that help the adult sense wind, gravity, and the position of head, body, wings, legs, antennae, and other body parts. In monarchs, setae on the adult’s antennae sense both touch and smell. (from monarchwatch.com).

In the photo below, a ventral view of the lower wings where they meet at their lowest point, there is also a delicate fringe visible along the edges. This could have aerodynamic as well as sensory functions.

papilio 46 CLOSE.jpg

From pointillism to nanostructures

Parts of the markings that appear as solid areas to our eye are revealed to be pointillist creations. I suspect we would need to know much more than we do about the vision of butterflies (and their predators?), in order to understand how these markings work for them.

Papilio42 CLOSE 1.jpg

The odd squareness of the smallest dots of color is not some pixellation in the photo, but an accurate representation. It shows the shape of the overlapping scales which form the surface of butterfly wings. Here are some microphotographs of wing scales at various magnifications, from Wikipedia.

ButterflyWingScales.jpg

And here are color microphotographs showing the same squared-off dots along with the underlying scale pattern.

MicrophotographButterflyWingScales.jpg

Picture source.


It’s been known for some time that the colors of butterfly wings are partly from pigments but mostly from the microstructure of the scales, scattering light to produce the colors. Blues, greens, reds and iridescence are usually structural, while blacks and browns come from pigments. (Wikipedia).

But now we know more, and the more we know the more intricate and amazing it is. Research (published this past June) has been able to identify the light-scattering shapes from the wings of several butterfly species, and they are described as “ ’mind-bendingly weird’ three-dimensional curving structures… [resembling] a network of three-bladed boomerangs”. The name for these crystalline forms is gyroids, and they were first described

in 1970 by NASA physicist Alan Schoen in his theoretical search for ultra-light, ultra-strong materials for use in space. Gyroids have what’s known as an ‘infinitely connected triply periodic minimal surface’: for a given set of boundaries, they have the smallest possible surface area. The principle can be illustrated in soap film on a wireframe (see image below). Unlike soap film, however, the planes of a gyroid’s surface never intersect. As mathematicians showed in the decades following Schoen’s discovery, gyroids also contain no straight lines, and can never be divided into symmetrical parts. (source, text and soap-bubble photo: wiredscience.com)

Gyroid-like soap bubble.jpg

Gyroid-like soap bubble. Photo from wiredscience.com

So gyroids were introduced to humans as an imagined created form, something that is a mind-boggler for non-mathematicians to envision.

gyroid_hex.jpg

The image above is a mathematician’s representation of one of the simpler types of gyroid.

Materials scientists have learned how to make synthetic gyroids for photonic devices, such as solar cells and communication systems, that manipulate the flow of light.

gyroidProcess.jpg

A self-assembled solar cell begins with one of two polymers forming a “gyroid” shape while the other fills in the space around it. The inner polymer is dissolved away to create a mold that is filled with a conductor of electrons. The outer polymer is then burned away, the conductor is coated with a photosensitive dye, and finally the surrounding space is filled with a conductor of positive “holes”. A solar reaction takes place at all the interfaces throughout the material, and the interlocking gyroid structure efficiently carries away the current. (Source for image and caption, Cornell Univ.)

And when Yale evolutionary ornithologist Richard Prum got curious about exactly how butterfly wing-scales twisted light, he found gyroids. His team had to use an advanced microscopy technique with nanoscale resolution, called synchrotron small angle X-ray scattering, in order to see them, but there they were. (See note at end for citation of article in PNAS.)

The butterfly’s gyroids are made of chitin, not exactly the flashy material I would associate with iridescent wings. It’s

the tough starchy material that forms the exterior of insects and crustaceans. Chitin is usually deposited on the outer membranes of cells. The Yale team wanted to know how a cell can sculpt itself into this extraordinary form, which resembles a network of three-bladed boomerangs. They found that, essentially, the outer membranes of the butterfly wing scale cells grow and fold into the interior of the cells. The membranes then form a double gyroid—or two, mirror-image networks shaped by the outer and inner cell membranes. Double gyroids are easier to self assemble but they are not as good at scattering light as a single gyroids. Chitin is then deposited in the outer gyroid to create a single solid crystal. The cell then dies, leaving behind the crystal nanostructures on the butterfly wing.

“Like engineers, butterflies grow their optically efficient single gyroids through a series of steps that make this complex shape easier to achieve. Photonic engineers are using gyroid shapes to try to create more efficient solar cells and, by mimicking nature, may be able to produce more efficient optical devices as well,” Prum said. (Source)

In an interview about the work, Richard Prum said “We’re still trying to wrap our brains around gyroids and what they are.” The shapes seem to have evolved separately in several lineages of butterflies.

”It’s a Swiss cheese,” he adds, “with spiraling channels of air traveling through it that intersect one another. But those channels actually travel in three different dimensions through the cheese, and what you end up with is this very complicated form left behind, and that form is a gyroid.”

And while the idea of butterflies with Swiss cheese wings is slightly strange, Prum says it’s a very useful one for scientist and engineers looking for the next leap forward in electronic technology.

For example, Prum says, take the fiber-optic cables that carry phone calls under the ocean. These cables carry signals in the form of colored light, but it’s very difficult to insulate them well enough to prevent light from leaking out. Current transoceanic cables have to have booster stations built along them to keep the signal strong. But a layer of gyroids around the fiber-optic cable “would act like a perfect insulation to that fiber,” Prum says. The same tiny structures that give the Emerald-patched Cattleheart its lovely green patches could also be used to keep green light from escaping a fiber-optic cable.

ButterflyScalesGreen.jpg

The vivid green color of the scales of this Papilionid butterfly are produced by optically efficient single gyroid photonic crystals. Caption and photo from www.physorg.com

Right now, it’s expensive and impractical to manufacture gyroids small enough to do that job. But butterflies hold the secret to growing them naturally. “If you could grow one, at exactly the right scale, as butterflies do,” says Prum, “you could make these things a lot easier.” (NPR interview, Jul 3, 2010)

This is a fine example of how curiosity can lead us to unexpected discoveries. The original question is one that could be used by certain Congressional anti-intellectuals in their periodic efforts to discredit basic research: “Imagine, all this work to find out what makes the color on butterfly wings! How ridiculous!” The research and technological developments that are thought “useful” by these folks had their origins in someone’s basic research, sparked by human curiosity. From butterfly wing-color to, perhaps, more efficient fiber-optic cables or solar energy collectors. It’s called bioengineering: investigating the functions and structures of nature, to derive principles and patterns for technological innovations. But for me it’s satisfying in itself, the revelation of these marvelous structures, underlying the evanescent beauty of a butterfly.

Papilio rutulus.jpg

Western Tiger Swallowtail butterfly on Buddleia bloom. Photo by terwilliger911, flickr.

Note: The article describing gyroids as the structure causing some colors in butterfly wings is:
Structure, function, and self-assembly of single network gyroid (I4132) photonic crystals in butterfly wing scales.
Vinodkumar Saranathan et al. Proceedings of the National Academy of Sciences. Published online before print June 14, 2010, doi: 10.1073/pnas.0909616107. The abstract is available free, but the article requires purchase or subscription to PNAS. There is a supplementary article here that contains some interesting images and very technical text. There’s even a movie you can watch showing a slice-by-slice trip through a certain sort of gyroid, or as the text says, though “the pentacontinuous volume of a level set core-shell double gyroid structure”.