We take a break from our regularly scheduled write-ups of peer-reviewed science to bring you this amusing image from FAILblog.

Now, it’s understandable that the Venus Flytrap – a carnivorous plant that catches insects – isn’t doing that well out of this situation, but I submit to you that it’s a win for the spider. The flytrap attracts insects to its hinged leaves by baiting them with a sweet nectar, and what better place for a spider to spin its web than a ready-made insect lure?

There are certainly other cases of spiders exploiting carnivorous plants. Several species of crab spiders make a living by exploiting the insect-catching traps of pitcher plants, waiting at the rim to grab passing insects. Some species even dive into the pool of fluid at the bottom of the pitcher to feed on the bodies at the bottom, using a bubble of air as a scuba tank. It wouldn’t surprise me to see further examples of spiders adapting to exploit carnivorous plants.

(I think it’s reasonable to assume that the spider whose web features in the photo wasn’t itself eaten; the trap would have had to close, which would have collapsed the web).

For long journeys, the shell of a snail hardly seems like the ideal public transport. That is, of course, unless you’re an even smaller snail…

Yasunori Kano from the University of Miyazaki has found that the babies of Neritina asperulata, a tiny snail just 3 millimetres across, hitchhike on the back of a larger species Neritina pulligera. This living bus is about 2 centimetres long, and dwarfs its passengers by more than seven times.

The hitchhiking snail is a special sort of parasite, and one that Kano thinks has never been described before. They don’t use their hosts as a snack, a home, an incubator or a foster parent – they simply treat them as a vehicle. Other parasites may unwittingly migrate in the bodies of their hosts, but there’s no evidence that these travels are intentional. N.asperulata, on the other hand, is completely dependent on the movements of other host snails. Without them, it would never get to the small rivers it needs to complete its life cycle.

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Nocturnal animals face an obvious challenge: collecting enough light to see clearly in the dark. We know about many of their tricks. They have bigger eyes and wider pupils. They have a reflective layer behind their retina called the tapetum, which reflects any light that passes through back onto it. Their retinas are loaded with rod cells, which are more light-sensitive than the cone cells that allow for colour vision.

But they also have another, far less obvious adaptation – their rod cells pack their DNA in a special way that turns the nucleus of each cell into a light-collecting lens. Their unconventional distribution is shared by the rods of nocturnal mammals from mice to cats. But it’s completely opposite to the usual genome packaging in the rods of day-living animals like primates, pigs and squirrels, and indeed, in almost all other eukaryotic cells.

In our cells, massive lengths of DNA are packaged into small spaces by wrapping them around proteins. These DNA-protein unions are known as chromatin, and they come in two different forms. Euchromatin is lightly packed and resembles a string of beads. Wrapping DNA in this way puts it within easy reach of other proteins and allows its genes to be actively transcribed. But imagine scrunching up that string of beads and you get heterochromatin – a tight, condensed ball of repressed genes that proteins cannot reach.

The two forms of chromatin are found in different areas, with euchromatin spread throughout the nucleus and heterochromatin concentrated at its edges. That pattern is nigh-universal and it applies from amoebae to plants to animals. There are only a few exceptions to this rule, including a minority of single-celled species and surprisingly, the rod cells in the eyes of nocturnal mammals. Now, Irina Solovei from the Ludwig-Maximilians University in Munich had found that this inverted distribution helps these species to see in the dark.

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Studying the way an animal moves by looking at its ears might seem like a poorly thought-out strategy. After all, short of watching it directly, most biologists would choose to look at more obvious traits like tracks, or limb bones.

But while an animal’s limbs may drive it forward, its inner ear makes sure that it doesn’t immediately fall over. By controlling balance, it plays a key role in movement, and its relative size can tell us about how agile an animal is.

When we walk, the image that forms on our retinas changes quite considerably. But no matter how fast or erratically we move, our view of the world neither jerks nor judders. It’s all stable images and smooth transitions, and the inner ear plays a large role in that.

In the inner ear, three semicircular canals control our balance by acting like small gyroscopes. The canals are bony, fluid-filled tubes arranged at right angles to each other and send information to the brain about the body’s orientation.

When the body moves, so does the fluid and this sloshing is sensed by hairs in the canals and relayed to the brain. The muscles of the neck and eye tense reflexively in response to these signals, and these help to stabilise our view of the world.

In humans, the inner ear doesn’t really have to work too hard – we’re limited to moving on the ground, and not very quickly at that. It’s a whole different story for a fast and agile animal like a bat, twisting and turning in three-dimensional airspace while avoiding obstacles and predators.

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A large study weighs up the existing evidence on the impact of GM crops on local insect life, providing some much-needed scientific rigour to the GM debate.

In Europe, the ‘GM debate‘ about the merits and dangers of genetically-modified (GM) crops is a particularly heated one. There is a sense of unease about the power of modern genetic technology, and a gut feeling that scientists are ‘playing God‘. These discontents are stoked by the anti-GM camp, who describe GM crops with laden and fear-mongering bits of unspeak like ‘Frankenstein foods‘ and ‘unnatural’.

In a debate so fuelled by emotion and personal values, scientific research and a critical analysis of the evidence rarely gets a look-in. But science has to grudgingly admit some blame in this, because there is actually precious little research on the safety of GM crops. And many of the studies that have been done were short-term and poorly replicated.

A lack of research is dangerous. It provides opening for people on either side of the debate to quote single, small studies as canon and brushing aside any research that contrasts with their stances.

Michelle Marvier and colleagues from Santa Clara University, California, are trying to change all that. They have analysed over 42 field experiments on GM crops to get an overall picture about their safety. The technique they used is called meta-analysis, a statistical tool that asks “What does everyone think?” It works on the basis that individual small studies may be far from conclusive, but pooling their results together can lead to stronger and more accurate results.

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Antarctica normally conjures images of white and blue, but the frozen continent can sometimes bear more unexpected colours. Take the Taylor Glacier – when geologist Griffith Taylor first explored it a century ago, he found a bizarre reddish stain that seemed to spill waterfall-like from the glacier’s snout. The area became evocatively known as Blood Falls. 

The source of the blood-red colour is an underground saltwater lake that was trapped by the encroaching glacier at least 1.5 million years ago. The temperature of the water is -5 Celsius, but it’s so salty that it doesn’t freeze. It’s also rich in iron salts, which are slowly leaching the ice – these are the source of the distinctive red hue. Blood Falls is a rust glacier.

But it also houses another secret, which scientists from Harvard University have started to uncover – it’s home to an entire ecosystem of bacteria, trapped for millennia in conditions that could hardly be more inhospitable to life.

Neither water from the surface nor light from the sun penetrates the thick ice of Taylor Glacier to the lake lying 400 metres beneath. As the glacier slides overhead, trace amounts of gases might seep through, but nothing substantial. There’s hardly any oxygen dissolved in the water, and radioactive-dating of the little carbon suggests that it is incredibly old. But despite the extremely salty water and the lack of light, oxygen and carbon, the microbes have lived there for millions of years, using sulphate ions as their only source of energy.

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In American high schools, black students typically perform worse than their white peers, which can damage their self-esteem and their future prospects. Studies have found that the fear of living up to this underachieving stereotype can cause so much stress that a child’s performance suffers. Their teachers may even write them off as lost causes, and spend less time on them.

With so many students caught in this vicious cycle, where the stereotype of poor performance strengthens itself, it might seem absurd to suggest that you could turn things round in less than an hour. But try telling that to Geoffrey Cohen from the University of Colorado.

In 2007, he showed that a simple 15-minute writing exercise at the start of a school year could boost the grades of black students by the end of the semester. The assignment was designed to boost the student’s sense of self-worth, and in doing so, it helped to narrow the typical performance gap that would normally separate them from white students. Now, Cohen returns with a new report of the same experiment two years on.

Things are still looking good. Even though two years have passed, the students are still feeling the benefits of those precious exercises. With the help of a couple of booster sessions, they still felt more confident about their chances of success, their grade point averages had increased (particularly among the weakest students), and the proportion who had to repeat a grade was two-thirds lower.

Cohen originally asked a group of white and black seventh-graders to write about a topic that they felt was important – from having good friends, to sense of humour, to musical ability – and why it mattered to them. The idea was to encourage the students to affirm their own abilities and their integrity, as a sort of psychological vaccine against the negative effects of stereotypes. As a control, a second group of students had to write about something they felt was not important, and why it mattered to someone else. Teachers, incidentally, were never told which student was completing which assignment and they were largely kept in the dark about the exercises and the aims of the experiments.

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Autumn is a time of incredible beauty, when the world becomes painted in the red, orange and yelllow palette of falling leaves. But there may be a deeper purpose to these colours, and the red ones in particular. In the eyes of some scientists, they aren’t just decay made pretty – they are a tree’s way of communicating with aphids and other insects that would make a meal of it. The message is simple: “I am strong. Don’t try it.”

During winter, trees withdraw the green chlorophyll from their leaves, and textbooks typically say that autumn colours are produced by the pigments that are left behind. That’s certainly true of yellows and oranges, but reds and purples are a different story.

They are the result of pigments called anthocyanins, which trees have to actively make. That uses up energy, which is lost to the tree when the leaf falls. An investment like that implies a purpose, and that’s what scientists have been trying to uncover.

Shortly before he died in 2000, the great William Hamilton (he of kin selection fame) suggested that autumn colours are a warning to insects. Many species, such as aphids, lay eggs in trees during autumn and their larvae feed off their host when spring arrives. That’s bad news for the tree, which defends itself with insecticidal poisons. Those that are particularly well-defended would benefit from advertising themselves as inhospitable hosts, and Hamilton suggested that they do this through red leaves.

Hamilton found some support for the idea – for example, he showed that trees that have the strongest autumn colours are also those that are plagued by the widest array of aphid pests. But his former student, Mario Archetti from the University of Oxford, has truly championed the theory and his latest findings provide the strongest support for it yet. They show that aphids avoid red-leaved apple trees, that they fare better on trees without them and that wild trees have far redder leaves than domesticated ones, which are less troubled by the challenges of insects.

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On November 1^st, 1700, an entire dynasty of kings came to a crashing end with the death of Charles II of Spain. Charles had neither a pleasant life nor a successful reign. He was physically disabled, mentally retarded and disfigured. A large tongue made his speech difficult to understand, he was bald by the age of 35, and he died senile and wracked by epileptic seizures. He had two wives but being impotent, he had no children and thus, no heirs. Which is what happens after 16 generations of inbreeding.

Charles II was the final king of the Spanish Habsburg dynasty (see family tree), part of a house that ruled over much of Europe for centuries and which took Spain to the height of its international power. Concerned with corralling their heritage within their bloodlines, the Spanish Habsburgs married heavily between each other. Most of their 11 marriages were between blood relatives, including several matches between first cousins and two between uncles and nieces. Charles’s own mother was the niece of his father, and his grandmother was also his aunt.

Historians have often speculated that this inbreeding was the dynasty’s downfall and contributed to Charles II’s numerous health problems. The more closely related a child’s parents are, the greater the odds that they will be dealt a dud genetic hand. We inherit one copy of almost every gene from our father and one from our mother. Some will be defective, but chances are that a second working copy will compensate for this. But if parents are related, they may already share many of the same genes and they risk of passing down an identical pair of faulty ones to their children. That can lead to genetic disorders or birth defects, like those that afflicted poor Charles.

Through a fascinating piece of historical genetics, Gonzalo Alvarez from the University of Santiago de Compostela has confirmed that inbreeding caused the extinction of this dynasty. He traced the pedigree of the entire line back through 16 generations, including over 3,000 people.

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Learning a new language as an adult is no easy task but infants can readily learn two languages without obvious difficulties. Despite being faced with two different vocabularies and sets of grammar, babies pick up both languages at the same speeds as those who learn just one. Far from becoming confused, it seems that babies actually develop superior mental skills from being raised in a bilingual environment.

By testing 38 infants, each just seven months old, Agnes Melinda Kovacs and Jacques Mehler have found that those who are raised in bilingual households have better “executive functions“. This loose term includes a number of higher mental abilities that allow us to control more basic ones, like attention and motor skills, in order to achieve a goal. They help us to plan for the future, focus our attention, and block out instinctive behaviours that would get in the way. Think of them as a form of mental control.

The role of these abilities in learning multiple languages is obvious – they allow us to focus on one language, while preventing the other from interfering. Indeed, children and adults who learn to use two languages tend to develop better executive functions. Now, Kovacs and Mehler have found that even from a very young age, before they can actually speak, children develop stronger executive functions if they grow up to the sound of two mother tongues. They show a degree of mental control that most people their age would struggle to match.

Kovacs and Mehler worked with 14 babies who heard two languages from birth, and 14 who had experienced just one. The babies saw a computer screen with two white squares and heard a short, made-up word. After that, a puppet appeared in one of the squares. There were nine words in total, and each time the puppet appeared in the same place. As the test went on, all the babies started focusing on the correct square more frequently, showing that they had learned to anticipate the puppet’s appearance. That’s a simple task that doesn’t require much in the way of executive function.

The next nine trials used a different puppet that appeared in the other square. The infants’ job was to learn that the link between word and puppet had changed, but only the bilingual ones were good at this. Unlike their monolingual peers, they learned to switch their attention to the other square. To Kovacs and Mehler, this is a sign of superior mental control – they had to override what they had previously learned in order to pick up something new. The monolingual infants, however, behaved as babies their age usually do – they stick with responses that had previously paid off, even if situations change.

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