Category: Science News

{Researchers have found measurable brain changes in children after a single season of playing youth football, even without a concussion diagnosis, according to a new study published online in the journal Radiology.}

According to USA Football, there are approximately 3 million young athletes participating in organized tackle football across the country. Numerous reports have emerged in recent years about the possible risks of brain injury while playing youth sports and the effects it may have on developing brains. However, most of the research has looked at changes in the brain as a result of concussion.

“Most investigators believe that concussions are bad for the brain, but what about the hundreds of head impacts during a season of football that don’t lead to a clinically diagnosed concussion? We wanted to see if cumulative sub-concussive head impacts have any effects on the developing brain,” said the study’s lead author, Christopher T. Whitlow, M.D., Ph.D., M.H.A., associate professor and chief of neuroradiology at Wake Forest School of Medicine in Winston-Salem, N.C.

The research team studied 25 male youth football players between the ages of 8 and 13. Head impact data were recorded using the Head Impact Telemetry System (HITs), which has been used in other studies of high school and collegiate football to assess the frequency and severity of helmet impacts. In this study, HITs data were analyzed to determine the risk weighted cumulative exposure associated with a single season of play.

The study participants underwent pre- and post-season evaluation with multimodal neuroimaging, including diffusion tensor imaging (DTI) of the brain. DTI is an advanced MRI technique, which identifies microstructural changes in the brain’s white matter. In addition, all games and practices were video recorded and reviewed to confirm the accuracy of the impacts.

The brain’s white matter is composed of millions of nerve fibers called axons that act like communication cables connecting various regions of the brain. Diffusion tensor imaging produces a measurement, called fractional anisotropy (FA), of the movement of water molecules in the brain and along axons. In healthy white matter, the direction of water movement is fairly uniform and measures high in FA. When water movement is more random, FA values decrease, which has been associated with brain abnormalities in some studies.

The results showed a significant relationship between head impacts and decreased FA in specific white matter tracts and tract terminals, where white and gray matters meet.

“We found that these young players who experienced more cumulative head impact exposure had more changes in brain white matter, specifically decreased FA, in specific parts of the brain,” Dr. Whitlow said. “These decreases in FA caught our attention, because similar changes in FA have been reported in the setting of mild TBI.”

It is important to note that none of the players had any signs or symptoms of concussion.

“We do not know if there are important functional changes related to these findings, or if these effects will be associated with any negative long-term outcomes,” Dr. Whitlow said. “Football is a physical sport, and players may have many physical changes after a season of play that completely resolve. These changes in the brain may also simply resolve with little consequence. However, more research is needed to understand the meaning of these changes to the long-term health of our youngest athletes.”

{Researchers from the University of Stirling have explored the true impact of heading a soccer ball, identifying small but significant changes in brain function immediately after routine heading practice.}

The study from Scotland’s University for Sporting Excellence published in EBioMedicine is the first to detect direct changes in the brain after players are exposed to everyday head impacts, as opposed to clinical brain injuries like concussion.

A group of soccer ball players headed a ball 20 times, fired from a machine designed to simulate the pace and power of a corner kick. Before and after the heading sessions, scientists tested players’ brain function and memory.

Increased inhibition in the brain was detected after just a single session of heading. Memory test performance was also reduced by between 41 and 67 per cent, with effects normalising within 24 hours.

Whether the changes to the brain remain temporary after repeated exposure to a soccer ball and the long-term consequences of heading on brain health, are yet to be investigated.

Played by more than 250 million people worldwide, the ‘beautiful game’ often involves intentional and repeated bursts of heading a ball. In recent years the possible link between brain injury in sport and increased risk of dementia has focussed attention on whether soccer ball heading might lead to long term consequences for brain health.

Cognitive neuroscientist Dr Magdalena Ietswaart from Psychology at the University of Stirling, said: “In light of growing concern about the effects of contact sport on brain health, we wanted to see if our brain reacts instantly to heading a soccer ball. Using a drill most amateur and professional teams would be familiar with, we found there was infact increased inhibition in the brain immediately after heading and that performance on memory tests was reduced significantly.

“Although the changes were temporary, we believe they are significant to brain health, particularly if they happen over and over again as they do in soccer ball heading. With large numbers of people around the world participating in this sport, it is important that they are aware of what is happening inside the brain and the lasting effect this may have.”

Dr Angus Hunter, Reader in Exercise Physiology in the Faculty of Health Sciences and Sport, added: “For the first time, sporting bodies and members of the public can see clear evidence of the risks associated with repetitive impact caused by heading a soccer ball.

“We hope these findings will open up new approaches for detecting, monitoring and preventing cumulative brain injuries in sport. We need to safeguard the long term health of soccer ball players at all levels, as well as individuals involved in other contact sports.”

Dr Ietswaart and Dr Hunter were supported in the research by Stirling neuropsychologist Professor Lindsay Wilson and PhD student Tom Di Virgilio, consulting with leading Glasgow University Medical School Neuropathologist Dr Willie Stewart and a wider multi-disciplinary team.

In the study, scientists measured levels of brain function using a basic neuroscience technique called Transcranial Magnetic Stimulation (TMS). The findings from this study, funded by the NIHR Brain Injury Healthcare Technology Cooperative (HTC) are the first to show the TMS technique can be used to detect changes to brain function after small, routine impacts.

{Telling small lies desensitizes our brains to the associated negative emotions and may encourage us to tell bigger lies in future.}

Telling small lies desensitises our brains to the associated negative emotions and may encourage us to tell bigger lies in future, reveals new UCL research funded by Wellcome and the Center for Advanced Hindsight.

The research, published in Nature Neuroscience, provides the first empirical evidence that self-serving lies gradually escalate and reveals how this happens in our brains.

The team scanned volunteers’ brains while they took part in tasks where they could lie for personal gain. They found that the amygdala, a part of the brain associated with emotion, was most active when people first lied for personal gain. The amygdala’s response to lying declined with every lie while the magnitude of the lies escalated. Crucially, the researchers found that larger drops in amygdala activity predicted bigger lies in future.

“When we lie for personal gain, our amygdala produces a negative feeling that limits the extent to which we are prepared to lie,” explains senior author Dr Tali Sharot (UCL Experimental Psychology). “However, this response fades as we continue to lie, and the more it falls the bigger our lies become. This may lead to a ‘slippery slope’ where small acts of dishonesty escalate into more significant lies.”

The study included 80 volunteers who took part in a team estimation task that involved guessing the number of pennies in a jar and sending their estimates to unseen partners using a computer. This took place in several different scenarios. In the baseline scenario, participants were told that aiming for the most accurate estimate would benefit them and their partner. In various other scenarios, over- or under-estimating the amount would either benefit them at their partner’s expense, benefit both of them, benefit their partner at their own expense, or only benefit one of them with no effect on the other.

When over-estimating the amount would benefit the volunteer at their partner’s expense, people started by slightly exaggerating their estimates which elicited strong amygdala responses. Their exaggerations escalated as the experiment went on while their amygdala responses declined.

“It is likely the brain’s blunted response to repeated acts of dishonesty reflects a reduced emotional response to these acts,” says lead author Dr Neil Garrett (UCL Experimental Psychology). “This is in line with suggestions that our amygdala signals aversion to acts that we consider wrong or immoral. We only tested dishonesty in this experiment, but the same principle may also apply to escalations in other actions such as risk taking or violent behaviour.”

Dr Raliza Stoyanova, Senior Portfolio Developer, in the Neuroscience and Mental Health team at Wellcome, said: “This is a very interesting first look at the brain’s response to repeated and increasing acts of dishonesty. Future work would be needed to tease out more precisely whether these acts of dishonesty are indeed linked to a blunted emotional response, and whether escalations in other types of behaviour would have the same effect.”

{Losing the youthful firmness and elasticity in our skin is one of the first outward signs of aging. Now it seems it’s not just our skin that starts to sag — but our brains too.}

New research from Newcastle University, UK, in collaboration with the Federal University of Rio de Janeiro, investigated the way the human brain folds and how this ‘cortical folding’ changes with age.

Linking the change in brain folding to the tension on the cerebral cortex — the outer layer of neural tissue in our brains — the team found that as we age, the tension on the cortex appears to decrease. This effect was more pronounced in individuals with Alzheimer’s disease.

Publishing their findings in the academic journal PNAS, the team say this new research sheds light on the underlying mechanisms which affect brain folding and could be used in the future to help diagnose brain diseases.

Lead author Dr Yujiang Wang, of Newcastle University, explains, “One of the key features of a mammalian brain is the grooves and folds all over the surface — a bit like a walnut — but until now no-one has been able to measure this folding in a consistent way.

“By mapping the brain folding of over 1,000 people, we have shown that our brains fold according to a simple universal law. We also show that a parameter of the law, which is interpreted as the tension on the inside of the cortex, decreases with age.

“In Alzheimer’s disease, this effect is observed at an earlier age and is more pronounced. The next step will be to see if there is a way to use the changes in folding as an early indicator of disease.”

Common in all mammals

The expansion of the cerebral cortex is the most obvious feature of mammalian brain evolution and is generally accompanied by increasing degrees of folding of the cortical surface.

In the average adult brain, for example, if the cortex of one side — or hemisphere — was unfolded and flattened out it would have a surface area of about 100,000 mm2, roughly one and a half times the size of a piece of A4 paper.

Previous research has shown that folding of the cortex across mammalian species follows a universal law — that is, regardless of size and shape, they all fold in the same way.

However, until now there has been no systematic study demonstrating that the same law holds within a species.

Tension slackens with age

“Our study has shown that we can use this same law to study changes in the human brain,” explains Dr Wang, based in Newcastle University’s world-leading School of Computing Science.

“From this, we identified a parameter that decreases with age, which we interpret as changing the tension on the cortical surface. It would be similar to the skin. As we age, the tension drops and the skin starts to slacken.

“It has long been known that the size and thickness of the cortex changes with age but the existence of a general law for folding shows us how to combine these quantities into a single measure of folding that can then be compared between genders, age groups and disease states.”

Women’s brains less folded

The team also found that male and female brains differ in size, surface area, and the degree of folding. Indeed, female brains tend to be slightly less folded than male brains of the same age. Despite this, male and female brains are shown to follow exactly the same law.

“This indicates that for the first time, we have a consistent way of quantifying cortical folding in humans,” says Dr Wang.

Throughout the lifespan of healthy individuals, cortical folding changes in the same way in both men and women but in those with Alzheimer’s disease the change in the brain folding was significantly different.

She adds: “More work is needed in this area but it does suggest that the effect Alzheimer’s disease has on the folding of the brain is akin to premature aging of the cortex.”

{Globally averaged concentration of carbon dioxide in the atmosphere reached the symbolic and significant milestone of 400 parts per million for the first time in 2015 and surged again to new records in 2016 on the back of the very powerful El Niño event, according to the World Meteorological Organization’s annual Greenhouse Gas Bulletin.}

CO2 levels had previously reached the 400 ppm barrier for certain months of the year and in certain locations but never before on a global average basis for the entire year. The longest-established greenhouse gas monitoring station at Mauna Loa, Hawaii, predicts that CO2 concentrations will stay above 400 ppm for the whole of 2016 and not dip below that level for many generations.

The growth spurt in CO2 was fuelled by the El Niño event, which started in 2015 and had a strong impact well into 2016. This triggered droughts in tropical regions and reduced the capacity of “sinks” like forests, vegetation and the oceans to absorb CO2. These sinks currently absorb about half of CO2 emissions but there is a risk that they may become saturated, which would increase the fraction of emitted carbon dioxide which stays in the atmosphere, according to the Greenhouse Gas Bulletin.

Between 1990 and 2015 there was a 37% increase in radiative forcing — the warming effect on our climate — because of long-lived greenhouse gases such as carbon dioxide, methane and nitrous oxide (N2O) from industrial, agricultural and domestic activities.

“The year 2015 ushered in a new era of optimism and climate action with the Paris climate change agreement. But it will also make history as marking a new era of climate change reality with record high greenhouse gas concentrations,” said WMO Secretary-General Petteri Taalas. “The El Niño event has disappeared. Climate change has not.”

“The recent agreement in Kigali to amend the so-called Montreal Protocol and phase out hydrofluorocarbons, which act as strong greenhouse gases, is good news. WMO salutes the commitment of the international community to meaningful climate action,” said Mr Taalas.

“But the real elephant in the room is carbon dioxide, which remains in the atmosphere for thousands of years and in the oceans for even longer. Without tackling CO2 emissions, we can not tackle climate change and keep temperature increases to below 2°C above the pre-industrial era. It is therefore of the utmost importance that the Paris Agreement does indeed enter into force well ahead of schedule on 4 November and that we fast-track its implementation.” he said.

WMO and partners are working towards an Integrated Global Greenhouse Gas Information System to provide information that can help nations to track the progress toward implementation of their national emission pledges, improve national emission reporting and inform additional mitigation actions. This system builds on the long-term experience of WMO in greenhouse gas observations and atmospheric modelling.

WMO is also striving to improve weather and climate services for the renewable energy sector and to support the Green Economy and sustainable development. To optimize the use of solar, wind and hydropower production, new types of weather services are needed.

{{Highlights of Greenhouse Gas Bulletin}}

The WMO Greenhouse Gas Bulletin reports on atmospheric concentrations of greenhouse gases. Emissions represent what goes into the atmosphere. Concentrations represent what remains in the atmosphere after the complex system of interactions between the atmosphere, biosphere, cryosphere and the oceans. About a quarter of the total emissions is taken up by the oceans and another quarter by the biosphere, reducing in this way the amount of CO2 in the atmosphere.

The Greenhouse Gas Bulletin provides a scientific base for decision-making. WMO released it ahead of the U.N. climate change negotiations in Marrakech, Morocco, to be held from 7 — 18 November 2016.

Carbon dioxide (CO2) accounted for about 65% of radiative forcing by long-lived greenhouse gases. The pre-industrial level of about 278 ppm represented a balance between the atmosphere, the oceans and the biosphere. Human activities such as the burning of fossil fuels has altered the natural balance and in 2015, globally averaged levels were 144% of pre-industrial levels. In 2015, global annual average concentration of CO2 concentrations reached 400.0 ppm. The increase of CO2 from 2014 to 2015 was larger than the previous year and the average over the previous 10 years.

In addition to reducing the capacity of vegetation to absorb CO2 the powerful El Niño also led to an increase in CO2 emissions from forest fires. According to the Global Fire Emission Database, CO2 emissions in Equatorial Asia — where there were serious forest fires in Indonesia in August-September 2015 — were more than twice as high as the 1997-2015 average.

Methane (CH4) is the second most important long-lived greenhouse gas and contributes to about 17% of radiative forcing. Approximately 40% of methane is emitted into the atmosphere by natural sources (e.g., wetlands and termites), and about 60% comes from human activities like cattle breeding, rice agriculture, fossil fuel exploitation, landfills and biomass burning. Atmospheric methane reached a new high of about 1845 parts per billion (ppb) in 2015 and is now 256% of the pre-industrial level.

Nitrous oxide (N2O) is emitted into the atmosphere from both natural (about 60%) and anthropogenic sources (approximately 40%), including oceans, soil, biomass burning, fertilizer use, and various industrial processes. Its atmospheric concentration in 2015 was about 328 parts per billion. This is 121% of pre-industrial levels. It also plays an important role in the destruction of the stratospheric ozone layer which protects us from the harmful ultraviolet rays of the sun. It accounts for about 6% of radiative forcing by long-lived greenhouse gases.

{{Other long-lived greenhouse gases}}

Sulphur hexafluoride is a potent long-lived greenhouse gas. It is produced by the chemical industry, mainly as an electrical insulator in power distribution equipment.

Atmospheric levels are about twice the level observed in the mid-1990s. Ozone-depleting chlorofluorocarbons (CFCs), together with minor halogenated gases, contribute about 12% to radiative forcing by long-lived greenhouse gases. While CFCs and most halons are decreasing, some hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), which are also potent greenhouse gases, are increasing at relatively rapid rates, although they are still low in abundance.

{Relationships between the ancestors of modern humans and other archaic populations such as Neanderthals and Denisovans were likely more complex than previously thought, involving interbreeding within and outside Africa, according to a new estimator developed by geneticists. Findings were reported at the American Society of Human Genetics (ASHG) 2016 Annual Meeting in Vancouver, B.C.}

In recent years, genetics has led to the revision of many assumptions about archaic populations, explained Ryan J. Bohlender, PhD, a postdoctoral researcher at the University of Texas MD Anderson Cancer Center and first author on the research. For example, the 2010 release of the Neanderthal genome led to the discovery that Neanderthals and the ancestors of modern Europeans interbred. A few years later, scientists discovered the existence of Denisovans, a population known of only through genetics, through a fossilized sample of DNA.

“My colleagues and I set out to find out what we might share with these ancient populations and how our histories interacted,” Dr. Bohlender said. They developed an estimation tool to model these interactions based on parameters such as current estimates of population size and dates when populations separated — how long ago they stopped interbreeding — and look for inconsistencies with information known from genetic studies about the overlap between the modern human genome and those of ancient populations. Compared to previous estimators, this one made increased use of genetic data to cut down on statistical bias. The researchers then allowed estimates of population size and separation dates to vary in a series of simulations, in order to find out if adjusting these parameters better fit the genetic data.

“Using this process, we found that the population in Africa was likely about 50 percent larger than previously thought. We also found that an archaic-modern human separation date of 440,000 years ago was the best fit, suggesting that Neanderthals diverged from our lineage 100,000 years more recently than we thought,” Dr. Bohlender said. “We got the same separation date using data from multiple modern human populations, which is a good sign.”

In addition, their results suggest that throughout Eurasia, ancient populations interbred less than previously believed, and that — contrary to previous findings — the level of mixing with Neanderthals did not differ significantly between Europe and East Asia.

The findings bring up many new questions, including to what extent the new estimator can be trusted, why it produces results that differ from prevailing estimates, and how to reconcile these differences.

“Overall, our findings confirm the human family tree is more complicated than we think it is,” Dr. Bohlender said. “For example, other archaic populations are likely to have existed, like the Denisovans, who we didn’t know about except through genetics.” They plan to try out simulations with multiple other populations, to see if this adds some clarity to the results.

Dr. Bohlender also believes that more detailed studies of African populations may shed some light. “Africans have been underrepresented in genetics research — they’re not as well studied as European and Asian populations, yet they are more diverse genetically than any other group,” he said.

{Dozens of dangerous gases are produced by the batteries found in billions of consumer devices, like smartphones and tablets, according to a new study. The research, published in Nano Energy, identified more than 100 toxic gases released by lithium batteries, including carbon monoxide.}

The gases are potentially fatal, they can cause strong irritations to the skin, eyes and nasal passages, and harm the wider environment. The researchers behind the study, from the Institute of NBC Defence and Tsinghua University in China, say many people may be unaware of the dangers of overheating, damaging or using a disreputable charger for their rechargeable devices.

In the new study, the researchers investigated a type of rechargeable battery, known as a “lithium-ion” battery, which is placed in two billion consumer devices every year.

“Nowadays, lithium-ion batteries are being actively promoted by many governments all over the world as a viable energy solution to power everything from electric vehicles to mobile devices. The lithium-ion battery is used by millions of families, so it is imperative that the general public understand the risks behind this energy source,” explained Dr. Jie Sun, lead author and professor at the Institute of NBC Defence.

The dangers of exploding batteries have led manufacturers to recall millions of devices: Dell recalled four million laptops in 2006 and millions of Samsung Galaxy Note 7 devices were recalled this month after reports of battery fires. But the threats posed by toxic gas emissions and the source of these emissions are not well understood.

Dr. Sun and her colleagues identified several factors that can cause an increase in the concentration of the toxic gases emitted. A fully charged battery will release more toxic gases than a battery with 50 percent charge, for example. The chemicals contained in the batteries and their capacity to release charge also affected the concentrations and types of toxic gases released.

Identifying the gases produced and the reasons for their emission gives manufacturers a better understanding of how to reduce toxic emissions and protect the wider public, as lithium-ion batteries are used in a wide range of environments.

“Such dangerous substances, in particular carbon monoxide, have the potential to cause serious harm within a short period of time if they leak inside a small, sealed environment, such as the interior of a car or an airplane compartment,” Dr. Sun said.

Almost 20,000 lithium-ion batteries were heated to the point of combustion in the study, causing most devices to explode and all to emit a range of toxic gases. Batteries can be exposed to such temperature extremes in the real world, for example, if the battery overheats or is damaged in some way.

The researchers now plan to develop this detection technique to improve the safety of lithium-ion batteries so they can be used to power the electric vehicles of the future safely.

“We hope this research will allow the lithium-ion battery industry and electric vehicle sector to continue to expand and develop with a greater understanding of the potential hazards and ways to combat these issues,” Sun concluded.

{Frequent viewing of selfies through social network sites like Facebook is linked to a decrease in self-esteem and life satisfaction, according to Penn State researchers in mass communications. “Most of the research done on social network sites looks at the motivation for posting and liking content, but we’re now starting to look at the effect of viewing behavior,” said Ruoxu Wang, graduate student in mass communications.}

Viewing behavior is also called “lurking” — when a person does not participate in posting or liking social content, but is just an observer. This form of participation in social media may sound like it should have little effect on how humans view themselves, but the study, published online in the Journal of Telematics and Informatics, revealed the exact opposite.

Wang and Fan Yang, graduate student in mass communications, conducted an online survey to collect data on the psychological effects of posting and viewing selfies and groupies. They worked with Wang’s graduate adviser, Michel Haigh, associate professor in communications. Posting behavior did not have significant psychological effects for participants. Viewing behavior did. They discovered the more often people viewed their own and others’ selfies, the lower their level of self-esteem and life satisfaction.

“People usually post selfies when they’re happy or having fun,” said Wang. “This makes it easy for someone else to look at these pictures and think your his or her life is not as great as theirs.”

Those participants categorized as having a strong desire to appear popular were even more sensitive to selfie and groupie viewing. In this case, however, Sselfie and groupie viewing behavior increased the self-esteem and life satisfaction for these participants, likely because this activity satisfied the participants’ desires to appear popular, according to the researchers.

Wang and Yang hope their work can raise awareness about social media use and the effect it has on viewers of people’s social networks.

“We don’t often think about how what we post affects the people around us,” said Yang. “I think this study can help people understand the potential consequences of their posting behavior. This can help counselors work with students feeling lonely, unpopular, or unsatisfied with their lives.”

{A newly-developed form of transistor opens up a range of new electronic applications including wearable or implantable devices by drastically reducing the amount of power used. Devices based on this type of ultralow power transistor, developed by engineers at the University of Cambridge, could function for months or even years without a battery by ‘scavenging’ energy from their environment.}

Using a similar principle to a computer in sleep mode, the new transistor harnesses a tiny ‘leakage’ of electrical current, known as a near-off-state current, for its operations. This leak, like water dripping from a faulty tap, is a characteristic of all transistors, but this is the first time that it has been effectively captured and used functionally. The results, reported in the journal Science, open up new avenues for system design for the Internet of Things, in which most of the things we interact with every day are connected to the Internet.

The transistors can be produced at low temperatures and can be printed on almost any material, from glass and plastic to polyester and paper. They are based on a unique geometry which uses a ‘non-desirable’ characteristic, namely the point of contact between the metal and semiconducting components of a transistor, a so-called ‘Schottky barrier.’

“We’re challenging conventional perception of how a transistor should be,” said Professor Arokia Nathan of Cambridge’s Department of Engineering, the paper’s co-author. “We’ve found that these Schottky barriers, which most engineers try to avoid, actually have the ideal characteristics for the type of ultralow power applications we’re looking at, such as wearable or implantable electronics for health monitoring.”

The new design gets around one of the main issues preventing the development of ultralow power transistors, namely the ability to produce them at very small sizes. As transistors get smaller, their two electrodes start to influence the behaviour of one another, and the voltages spread, meaning that below a certain size, transistors fail to function as desired. By changing the design of the transistors, the Cambridge researchers were able to use the Schottky barriers to keep the electrodes independent from one another, so that the transistors can be scaled down to very small geometries.

The design also achieves a very high level of gain, or signal amplification. The transistor’s operating voltage is less than a volt, with power consumption below a billionth of a watt. This ultralow power consumption makes them most suitable for applications where function is more important than speed, which is the essence of the Internet of Things.

“If we were to draw energy from a typical AA battery based on this design, it would last for a billion years,” said Dr Sungsik Lee, the paper’s first author, also from the Department of Engineering. “Using the Schottky barrier allows us to keep the electrodes from interfering with each other in order to amplify the amplitude of the signal even at the state where the transistor is almost switched off.”

“This will bring about a new design model for ultralow power sensor interfaces and analogue signal processing in wearable and implantable devices, all of which are critical for the Internet of Things,” said Nathan.

“This is an ingenious transistor concept,” said Professor Gehan Amaratunga, Head of the Electronics, Power and Energy Conversion Group at Cambridge’s Engineering Department. “This type of ultra-low power operation is a prerequisite for many of the new ubiquitous electronics applications, where what matters is function — in essence ‘intelligence’ — without the demand for speed. In such applications the possibility of having totally autonomous electronics now becomes a possibility. The system can rely on harvesting background energy from the environment for very long term operation, which is akin to organisms such as bacteria in biology.”

{Where did our jaws come from? The question is more complicated than it seems, because not all jaws are the same. In a new article, published in Science, palaeontologists from China and Sweden trace our jaws back to the extinct placoderms, armoured prehistoric fish that lived over 400 million years ago.}

Jaws are an iconic and defining feature, not only of our own anatomy but of all jawed vertebrates: not for nothing did Steven Spielberg use “Jaws” as the one-word title of his immortal shark epic.

Jaws first appear in the developing embryo as a cartilage bar similar to a gill arch. In a shark, this develops directly into the adult jaws, but in an embryo of a bony fish or a human being new bones appear on the outside of the cartilage. In our own skull, these bones — the dentary, maxilla and premaxilla — make up the entire jaws and carry our teeth.

It is universally accepted that the dentary, maxilla and premaxilla are a shared heritage of bony fishes and tetrapods: you will find these same bones in a crocodile or a cod. But what about further back? Only one other group of fishes, the extinct placoderms, have a similar set of jaw bones. But these bones, known as ‘gnathal plates’ and shown to spectacular effect in the giant placoderm Dunkleosteus where they are developed into blades like sheet-metal cutters, have always been regarded as unrelated to the dentary, maxilla and premaxilla. For one thing they are located slightly further inside the mouth, and in any case the general opinion has been that placoderms and bony fishes are only very distantly related.

The picture began to change fundamentally in 2013 with the description of Entelognathus, a Silurian (423 million year old) fossil fish from Yunnan in China which combines a classic placoderm skeleton with presence of a dentary, maxilla and premaxilla. Together with the discovery of placoderm-like characteristics in some of the earliest bony fishes, this began to build a strong case for a close relationship between placoderms and bony fishes, accompanied by a substantial carry-over of placoderm characteristics into bony fishes (and hence ultimately to us). But what about those jaws, where did they come from?

This is where the new fossil, Qilinyu, comes in. Qilinyu, described this week in Science by palaeontologists from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) in Beijing and Uppsala University in Sweden, comes from the same place and time period as Entelognathus, and also combines a placoderm skeleton with dentary, maxilla and premaxilla, though the two fishes otherwise look quite different and must have had different lifestyles. Looking at the jaw bones of Entelognathus and Qilinyu we can see that they, in both fishes, combine characters of the bony fish jaw bones (they contribute to the outer surface of the face and lower jaw) and placoderm gnathal plates (they have broad biting surfaces inside the mouth). Another thing becomes apparent as well: it has been argued that placoderm gnathal plates represent an inner jaw arcade, similar in position to the ‘coronoid bones’ of bony fishes, and if that were true we would expect to find gnathal plates just inside of the dentary, maxilla and premaxilla of Entelognathus and Qilinyu; but there is nothing there.

The simplest interpretation of the observed pattern is that our own jaw bones are the old gnathal plates of placoderms, lightly remodelled. It seems like substantial parts of our anatomy can be traced back, not only to the earliest bony fishes, but beyond them to the strange ungainly armoured placoderms of the Silurian period.