Illustrated Articles Edition

New Scientist magazine was launched in 1956 “for all those men and women who are interested in scientific discovery, and in its industrial, commercial and social consequences”. The brand’s mission is no different today - for its consumers, New Scientist reports, explores and interprets the results of human endeavour set in the context of society and culture.

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UV Vision

Sex In Space

Frankenstein Syndrome

Gaming Illusions

Green Machine

Diabetics

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UV VISIONJessica Griggs

Reindeer see their world in glorious ultraviolet, helping them find food and avoid predators.

Most mammals, including humans, see using light from the visible part of the spectrum; ultraviolet light, which has a shorter wavelength, is invisible. But not to reindeer, says Glen Jeffery of University College London.

The frozen wastes of the Arctic reflect around 90 per cent of the UV light that hits them; snow-free land typically reflects only a few per cent. So Jeffery and colleagues wondered whether reindeers had adapted to their UV-rich world.

In dark conditions, they shone LED lights of different wavelengths, including UV, into the eyes of 18 anaesthetised reindeers while recording with an electrode whether nerves in the eye fired, indicating that the light had been seen. The UV light triggered a response in the eyes of all the reindeer.

“Since migrating to the Arctic 10,000 years ago, these animals have adapted incredibly quickly,” says Jeffery.

The team’s experiments with a UV camera in the Arctic suggest why. They showed that urine – a sign of predators or potential mates – and lichens – a major food source for reindeers in the winter months – absorb UV light, making them appear black in contrast to the UV-reflecting snow.

“Very few mammals see UV light. Rodents do and some species of bat do but we have no idea why they have developed this capability,” says Jeffery. “This is the first time we have got a real handle on why a mammal uses UV light.”

The eyes of most mammals cannot cope with UV light because it carries enough energy to destroy their sensitive photoreceptors, permanently damaging vision. To prevent this happening

we experience “snow blindness”: our corneas respond to UV light by becoming temporarily cloudy, preventing excess amounts of UV reaching and burning the retina.

“Why don’t reindeer, arctic fox, polar bears or arctic seals get snow blindness?” asks Jeffery. “Arctic mammals must have a completely different mechanism for protecting their retinas.”

To try to shed light on this conundrum, Jeffery and his team plan to return to the Arctic later in the year. “If we could work out what this protective mechanism is perhaps we could learn from it and develop new strategies to prevent or treat the damage UV can cause to humans,” he says.

SEX IN SPACESujata GuptaPREGNANT women and their fetuses are not severely affected by air travel - but the same may not be true for space travel. Zebrafish embryos raised in microgravity have been shown to develop cranial defects.

The changes are “not going to be a problem for the health of the organism - yet”, says Tamara Franz-Odendaal, a developmental biologist at Mount Saint Vincent University in Halifax, Canada. She suspects the abnormalities are caused by changes in neural crest cells, which give rise to cranial cartilage and bone. With successive generations these effects could amplify, which doesn’t bode well for extended human space voyages.

The research, presented last week at the Society for Integrative Biology conference in Salt Lake City, Utah, adds to growing evidence that reproduction and space just don’t mix.

To mimic the weightlessness of space, Franz-Odendaal’s graduate student Sara Edsall placed fertilised zebrafish eggs inside a bioreactor, which spins objects within it to create a microgravity environment. She began spinning the eggs 10 to 14 hours after fertilisation to coincide with a key stage in the development of cranial neural crest cells, and stopped them 12 to 96 hours later.

Once the fish had hatched, Edsall stained the cranial cartilage in half of them blue. She then compared these to fish that hadn’t spent time in microgravity as embryos, and found that the branchial arches - bits of cartilage that support the gills and correspond to parts of the jaw in humans - appeared altered. To see if these problems persisted into adulthood, Edsall repeated the staining several months later on the second half of the group of fish. The adult fish were also abnormal: the bone at the base of their skull buckled, for example.

In 2002, Stephen Moorman, now at Robert Johnson Medical School in Piscataway, New Jersey, also found abnormalities in zebrafish eggs that had developed in microgravity. This time they were spun in a bioreactor 30 hours after fertilisation. Moorman found that the hatched fish developed deficits in their vestibular systems, responsible for balance (Developmental Dynamics, vol 223, p 285). The fish died after just two weeks.

Access to space missions is limited, so bioreactors allow researchers to conduct pseudo-space research here on Earth. Edsall hopes to carry out the zebrafish experiment in space in 2015.

The use of bioreactors is not without controversy, however. Kenneth Souza, a senior scientist at Dynamac Corporation which assists NASA, says bioreactors poorly mimic conditions in space, pointing out that medaka fish bred in space in 1995 showed no abnormalities. Edsall counters that the 1995 study did not have the same level of detail as hers, and so may have missed something.

What does seem clear is that space travel affects reproduction. Joseph Tash, a reproductive biologist at the University of Kansas Medical Center in Kansas City, examined 16 female mice that travelled aboard NASA’s STS-131 mission last year. He found that the mice had shrunken ovaries, dying ovarian follicles and down-regulated oestrogen genes. Their reproductive systems “had shut down”, he says.

FRANKENSTEIN SYNDROMEPhilip BallFrom IVF to artificial wombs, why does each advance in reproductive technology still conjure up visions of monsters or Hitler clones?

WHEN Ignacio Carrasco de Paula, the Vatican spokesman for bioethics, objected to IVF pioneer Robert Edwards receiving the 2010 Nobel prize for medicine, he stressed that he was speaking in a personal capacity.

But opposition to assisted conception is official papal policy. In 2004, Pope John Paul II condemned IVF as “a technology that wants to substitute true paternity and maternity and therefore that does harm to the dignity of parents and children alike”. The “conjugal act”, he said, “cannot be substituted by a mere technological procedure which is devoid of human value and subject to the dictates of science and technology”.

Now that more than 4 million babies globally have been conceived by IVF, this view seems seriously out of kilter with the world as most of us know it. Yet every fresh advance in technologies of “human manufacture”, from artificial wombs to sperm made from stem cells, elicits the same negative imagery as IVF initially did: references to Frankenstein, to Brave New World and the Faust legend, visions of resurrecting Adolf Hitler (or armies of Hitlers), and portrayals of the “artificial human” as a soulless creature that will ultimately supplant us.

The reaction of many scientists is to lament these “science fiction” stories, to imagine that if Mary Shelley and Aldous Huxley had never committed their imaginings to paper all would have been well. They fail to see that neither Shelley nor Huxley exactly invented their stories, because myths and legends of making people have always been with us, and have always spoken to deep-rooted fears and preconceptions about what this might entail – and what it would produce.

Some versions of the Prometheus story of Greek mythology say that he not only gave technological knowledge to humankind but actually created human beings. And the legendary inventor Daedalus was said to have been able to animate statues. Ancient Jewish folklore tells of the golem, a being animated from clay by magical means, while medieval alchemists were said to be able to make homunculi, little human-like forms cooked up in a sealed vessel, as later portrayed in Goethe’s telling of the Faust legend.

Crucially, all these examples of people-making – what I call anthropoeia – ended badly. The message was that this sort of dabbling in the work of the divine was apt to bring down speedy retribution, whether it was Prometheus suffering perpetual torment in chains, the golem-makers crushed by their wayward creatures, or Faust dragged to hell. The “manufactured being” itself was either subhuman, like the golem, or superhuman, like Goethe’s homunculus – but could never be just like us. Most significantly, it lacked a soul, the watermark of true humanity that only God could instil.

Mary Shelley combined some of these mythical elements with the electrical “galvanic” theory of physiology popular in the early 19th century, and in doing so she created a secular vision of anthropoeia in her Gothic novel. God is relegated to the wings, and it is left for the monster to deliver retribution on Victor Frankenstein, the modern Prometheus. Theatre and film insisted on their own versions, in particular refusing to grant the creature any eloquence: it was a pitiful, shambling mute in stage adaptations in London’s West End long before Boris Karloff stumbled across the screen.

In the 20th century, anthropoeia left the secluded lab and entered the factory, first in Karel Capek’s 1921 play R.U.R. in which the original robots were made of flesh and blood, from components assembled like Henry Ford’s automobiles.

Just a decade or so later, Aldous Huxley imagined a better way. The hatcheries of his Brave New World were extrapolated from early experiments on tissue culture and the vision of babies gestated in artificial wombs (ectogenesis) advocated by his brother, the biologist Julian, and their friend J. B. S. Haldane. The mass-produced people designed to fill castes were the forerunners of the clone armies of Star Wars.

From these stories, we have accumulated a roster of myths about reproductive technologies that now recur with dreary predictability with every new advance. Anthropoeia will be used for social engineering by dictators – or indeed to duplicate themselves; it will lead to the demise of the family; it will result in the annihilation of men (or women). We still find it hard to imagine that the clone – a term philosopher Gregory Pence considers as prejudicial as labels of racism – will, when born, be a person just like us.

These fears make little sense in themselves; some invoke more or less magical thinking. But their pull is relentless. Why do we insist that this “otherness” and this intervention in procreation are only steps towards aBrave New World? Partly, I think, it is a defence against the uncomfortable notion that we can be “manufactured”. But at root, making people (or merely appearing to do so, as in IVF and reproductive cloning) is arguably the ultimate “unnatural” act.

And what we generally fail to realise is that, when we call something unnatural, we are not just placing it in a different category from the “natural”. We are making a moral judgement – indeed, the same moral judgement Pope John Paul II was making about IVF. We are saying that it violates a perceived “natural order”, which in theological terms is associated with a purpose for all things designated by God, and which must therefore be intrinsically “good”. According to this view, the natural “purpose” of sexual intercourse is procreation, and so a new human life cannot morally begin without it. Today’s accusations of unnaturalness, and even

of playing God, are likely to come from a secular perspective that has merely replaced God with a reified nature.

The preconceptions and prejudices, derived from the cultural history of anthropoeia, that now surround reproductive technologies are still shaping the discourse. This was all too evident in the debates about human cloning and embryo research conducted by George W. Bush’s Council on Bioethics, which supported the administration’s decision to block federal funds for stem-cell research.

At a meeting in 2002, one member, Charles Krauthammer, claimed that cloning would enable “some people” to “manufacture extremely intelligent, extremely powerful, extremely resistant people” – nothing less, he said, than a “super-race”. The council’s chair, bioethicist Leon Kass, had warned back in 1971 that new reproductive technologies might lead to the “asexual reproduction of 10,000 Mao Tse-tungs”, and he has used mythical images to oppose such technologies every step of the way.

Kass feels that our instinctive aversion to some of these developments “is the emotional expression of deep wisdom, beyond reason’s power fully to articulate it” – something he calls the “wisdom of repugnance”. This notion should not be dismissed out of hand: for example, rational arguments for why it is not immoral to create headless, cloned embryos for spare parts surely can’t be the sole arbiter of whether that is a good idea. Our instinctive unease about making babies by human cloning cannot be ruled out in grappling with that possibility.

So how will we know when to heed repugnance and when not? There is no simple moral calculus. I believe the first question for new reproductive technologies should not be whether it is “right” in some timeless, absolute moral sense, but why we might want to do it. Not until we examine and acknowledge the roles that people-making myths, both ancient and modern, play in shaping our fears about these techniques can we have a grown-up debate about whether we want them.

GAMINGILLUSIONSJim Giles

You are playing a video game, and your avatar is creeping into a haunted house at the dead of night. Suddenly, you freeze in your chair. Something is crawling up your back...

Whether this idea appeals or not, researchers at Disney have made such sensations possible by inventing a system that fools players into thinking that objects are moving against their skin.

Their brainchild, known as Tactile Brush, creates the illusion of being touched by anything from falling rain to crawling insects.

One of the illusions the team employs is called apparent tactile motion. If two vibrating objects are placed close together on skin in quick succession, people often experience this as a single vibration moving between the two points of contact. In a related illusion, known as a phantom tactile sensation, a pair of stationary vibrations is sensed as a single stimulus placed in between the two.

Apparent motion has been around since the early 1900s and phantom sensation since 1957, but this is the first time anyone has used them to provide precise tactile feedback.

Ali Israr and Ivan Poupyrev at Disney Research Pittsburgh studied these illusions with the help of volunteers who sat in a chair backed by a grid of 12 vibrating coils. By operating the coils in different sequences and at different intensities, they worked out how to induce the sensations of apparent motion and also persuade the volunteers that they were feeling extra coils that didn’t exist, which creates a more realistic effect. Israr and Poupyrev incorporated these two illusions into software that controlled the coils, which convinced the person sitting in the chair that shapes were moving across their back.

At the Conference on Human Factors in Computing Systems, held last week

in Vancouver, Canada, the researchers demonstrated a driving game that makes use of Tactile Brush. Players feel a force from the chair that mimics the experiences of cornering and accelerating by activating the coils in sequence to sweep across the back.

In other early tests, Israr and Poupyrev have simulated the sensation of raindrops running down skin by tracing a vertical line downwards. Israr describes skin as an unexplored display surface. “Two metres squared - that’s the total area of our skin,” he says. “It’s a big area.”

The team is also working on a wearable device with vibrators in the sleeves and around the torso. Disney wants to develop systems that could augment the company’s amusement park rides. Israr suggests that riders could experience the sensation of wind and rain sweeping over them, or insects crawling over their backs.

“I’d really like to get it into movie theatres,” adds Poupyrev. He says it would help movies to compete with DVDs and home cinema. “3D is already there. Movie theatres will become more like amusement parks. Movies will engage all the senses.”

GREENMACHINEHelen KnightThe humble street light is joining the ranks of wind turbines and solar power plants in supplying renewable energy to the electricity grid.

A street lamp covered in photovoltaic cells, which can generate more energy from sunlight than it consumes to light the street, is being tested in the UK. And the lamp is already supplying electricity to the National Grid.

The SunMast, developed by Scotia, based in Aarhus, Denmark, generates electricity from sunlight during the day, which it supplies to the grid. It then simply draws electricity back from the grid at night to power its light.

If the trial in South Mimms in the UK is successful, the lamps could reduce the emissions produced by streetlights by 120 per cent, the company claims.

The photovoltaic solar cells, which are designed to generate electricity even on cloudy days, are fitted down the length of the mast, to increase their surface area. An inverter in the base of the lamp converts the DC electricity generated by the cells into AC for the grid.

Diabetics:Andy Coghlan

Diabetics: is it time to bin the insulin?

A pioneering hormone treatment may be the secret to an easy life for diabetics, consigning insulin shots and regular glucose monitoring to the medical history books.

Most people associate diabetes with insulin, the pancreatic hormone that dictates how much glucose circulates in blood. Type 1 diabetics have to inject the hormone because they can’t make it themselves. Now, the spotlight is turning on insulin’s lesser-known pancreatic twin, glucagon, as a treatment that could control blood glucose levels without the need for daily monitoring.

Whereas insulin clears surplus glucose from the blood after meals, squirrelling it away in the liver, muscles and elsewhere, glucagon does the opposite when we are hungry, ordering the liver to release stores of glucose “fuel” into the blood or to make more if none is available.

To investigate glucagon’s role, Roger Unger at the University of Texas Southwestern Medical Center in Dallas and colleagues engineered mice to lack glucagon receptors so they couldn’t respond to the hormone. Surprisingly, the mice had normal levels of blood glucose. Then, when the team used a toxin to destroy the pancreatic beta cells that make insulin, the mice remained diabetes-free.

“The bottom line is that without glucagon, you can’t get diabetes,” says Unger. Even more mystifying, when the mice consumed huge amounts of sugar in so-called “glucose tolerance” tests, their blood glucose levels remained normal, irrespective of whether or not they could make insulin (Diabetes, DOI: 10.2337/db10-0426).

“The implication for humans is that [without glucagon] you could drink 10 bottles of sugary

drinks and your blood sugar would remain the same, with or without insulin,” he says. “This was a huge surprise.”

So theoretically, if glucagon could be safely neutralised in people with type 1 diabetes, their blood glucose levels would stay normal without them having to take insulin or constantly check that level. “The only potential downside is too little glucose in the blood, or hypoglycaemia,” says Unger. But this would only likely become an issue if a person was due to run a marathon, or do something equally energy-sapping. “The answer would be to take a sugary drink with you,” he says.

The results in mice are so encouraging that a trial has already begun to see if suppressing glucagon has similar benefits in people with diabetes. Amylin Pharmaceuticals of San Diego, California, is attempting to do this with leptin, a hormone that controls fat uptake by cells but which also dampened the action of glucagon in studies on mice by Unger’s team in 2008.

“It’s the first time that researchers will test leptin, in the form of an analogue called metreleptin, in people with type 1 diabetes to see if it can improve glucose control,” a company spokeswoman told New Scientist. The volunteers will not go without insulin, but will receive the minimum safe amount.

Other diabetes researchers are encouraged, but cautious about the developments. “If you get rid of the glucagon receptor, you get these dramatic changes,” says Alan Cherrington of Vanderbilt University School of Medicine in Nashville, Tennessee. “But is it more relevant in rodents than in humans?” he asks.

Cherrington says that the study leaves important questions unanswered. Firstly, where does surplus glucose go in the mice lacking glucagon and insulin? Unger agrees that this urgently

needs investigation and says that tracer studies are under way with labelled glucose so its fate in the animals can be tracked. The most likely destination, according to Cherrington, is the liver, but if so, what happens when it is “full up”?

The key question is: how are the mice managing to regulate glucose if insulin is not involved? Cherrington’s hunch is that glucagon-like peptide-1 (GLP-1), a hormone made in the gut, may be deputising. “GLP-1 may affect the liver and muscle in an insulin-like way, ordering them to store glucose,” he says.

Daniel Drucker at the Samuel Lunenfeld Research Institute in Toronto, Canada, who investigates GLP-1 and glucagon, agrees. “Animal models show elimination of glucagon is associated with increased circulation of GLP-1, so this hormone may certainly be playing a role,” he says.

Drucker also says that suppressing glucagon levels, as expected in the leptin treatment, is probably safer than completely blocking the receptors. That’s because blocking causes the cells that make glucagon to multiply rapidly to increase glucagon output, potentially resulting in the development of a pancreatic tumour. This shouldn’t happen if glucagon action is only dampened.

Another question, of course, is how the finding will translate to people with type 1 diabetes, says Robert Henry of the University of California at San Diego, who is head of medicine and science for the American Diabetic Association. “The animals don’t have any glucagon activity from birth, so would blocking the hormone have different effects in animals or humans already producing it?” he says.

Although cautious, most commentators were confident that the finding could lead to new treatments, or at the very least to new insights challenging the historical pre-eminence of insulin. “It raises a large number of issues challenging the classic dogma that insulin is the most important hormone in diabetic control,” says Henry.