Dec 12, 2017

Action games expand the brain's cognitive abilities, study suggests

This study focuses on one specific video game genre, action video (war or shooter) games that have long been considered as mind-numbing.
The human brain is malleable -- it learns and adapts. Numerous research studies have focused on the impact of action video games on the brain by measuring cognitive abilities, such as perception, attention and reaction time. An international team of psychologists, led by the University of Geneva (UNIGE), Switzerland, has assembled data from the last fifteen years to quantify how action video games impact cognition. The research has resulted in two meta-analyses, published in the journal Psychological Bulletin, which reveal a significant improvement in the cognitive abilities of gamers.

Psychologists have been studying the impact of video games on the brain ever since the late 80s, when Pacman and arcade games first took roots. The present study focuses on one specific video game genre, action video (war or shooter) games that have long been considered as mind-numbing. Do they influence the cognitive skills of players?

"We decided to assemble all the relevant data from 2000 to 2015 in an attempt to answer this question, as it was the only way to have a proper overview of the real impact of action video games," explains Daphné Bavelier, professor in the Psychology Section at UNIGE's Faculty of Psychology and Educational Sciences (FPSE). Psychologists from UNIGE and the universities of Columbia, Santa Barbara and Wisconsin dissected the published literature (articles, theses and conference abstracts) over the course of a year. In addition, they contacted over sixty professors, asking them for any unpublished data that might throw light on the role of action video games. Two meta-analyses emerged from the research.

Profile of action gamers

A total of 8,970 individuals between the ages of 6 and 40, including action gamers and non-gamers, took a number of psychometric tests in studies conducted by laboratories across the world with the aim of evaluating their cognitive abilities. The assessments included spatial attention (e.g. quickly detecting a dog in a herd of animals) as well as assessing their skills at managing multiple tasks simultaneously and changing their plans according to pre-determined rules. It was found that the cognition of gamers was better by one-half of a standard deviation compared to non-gamers.

However, this first meta-analysis failed to answer a crucial question. "We needed to think about what the typical gamer profile is," points out Benoit Bediou, researcher in the FPSE Psychology Section. "Do they play action-type video games because they already have certain cognitive skills that make them good players; Or, on the contrary, are their high cognitive abilities actually developed by playing games?"

Training your brain by playing action video games

The psychologists proceeded to analyze intervention studies as part of the second meta-analysis. 2,883 people (men and women) who played for a maximum of one hour a week were first tested for their cognitive abilities and then randomly divided into two groups: one played action games (war or shooter games), the other played control games (SIMS, Puzzle, Tetris). Both groups played for at least 8 hours over a week and up to 50 hours over 12 weeks. At the end of the training, participants underwent cognitive testing to measure any changes in their cognitive abilities. "The aim was to find out whether the effects of action gaming on the brain are causal," continues Bavelier, adding: "That's why these intervention studies always compare and contrast a group that is obliged to play an action game with one obliged to play a video control game, where the mechanics are very different. This active control group ensures that the effects resulting from playing action games really do result from the nature of this kind of game. In other words, they are not due to being part of a group that is asked to undertake an engrossing task or that is the centre of scientific attention (placebo effect)."

The results were beyond dispute: individuals playing action videos increased their cognition more than those playing the control games with the difference in cognitive abilities between these two training groups being of one-third of a standard deviation. "The research, which was carried out over several years all over the world, proves the real effects of action video games on the brain and paves the way for using action video games to expand cognitive abilities," argues Bediou.

Despite the good news for avid gamers, it is worth highlighting that these beneficial effects were observed in studies that asked individuals to space their game play out over a period of many weeks to months rather than to engage in a large amount of gaming in a single sitting. As is true in any learning activity, short bouts of repeated practice is much preferred over binging!

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Telescopes team up to study giant galaxy

The giant radio galaxy Centaurus A as observed by the Murchison Widefield Array telescope.
Astronomers have used two Australian radio telescopes and several optical telescopes to study complex mechanisms that are fuelling jets of material blasting away from a black hole 55 million times more massive than the Sun.

In research published today, the international team of scientists used the telescopes to observe a nearby radio galaxy known as Centaurus A.

"As the closest radio galaxy to Earth, Centaurus A is the perfect 'cosmic laboratory' to study the physical processes responsible for moving material and energy away from the galaxy's core," said Dr Ben McKinley from the International Centre for Radio Astronomy Research (ICRAR) and Curtin University in Perth, Western Australia.

Centaurus A is 12 million light-years away from Earth -- just down the road in astronomical terms -- and is a popular target for amateur and professional astronomers in the Southern Hemisphere due to its size, elegant dust lanes, and prominent plumes of material.

"Being so close to Earth and so big actually makes studying this galaxy a real challenge because most of the telescopes capable of resolving the detail we need for this type of work have fields of view that are smaller than the area of sky Centaurus A takes up," said Dr McKinley.

"We used the Murchison Widefield Array (MWA) and Parkes -- these radio telescopes both have large fields of view, allowing them to image a large portion of sky and see all of Centaurus A at once. The MWA also has superb sensitivity allowing the large-scale structure of Centaurus A to be imaged in great detail," he said.

The MWA is a low frequency radio telescope located at the Murchison Radio-astronomy Observatory in Western Australia's Mid West, operated by Curtin University on behalf of an international consortium. The Parkes Observatory is 64-metre radio telescope commonly known as "the Dish" located in New South Wales and operated by CSIRO.

Observations from several optical telescopes were also used for this work -- the Magellan Telescope in Chile, Terroux Observatory in Canberra, and High View Observatory in Auckland.

"If we can figure out what's going in Centaurus A, we can apply this knowledge to our theories and simulations for how galaxies evolve throughout the entire Universe," said co-author Professor Steven Tingay from Curtin University and ICRAR.

"As well as the plasma that's fuelling the large plumes of material the galaxy is famous for, we found evidence of a galactic wind that's never been seen -- this is basically a high speed stream of particles moving away from the galaxy's core, taking energy and material with it as it impacts the surrounding environment," he said.

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Electrical and chemical coupling between Saturn and its rings

Spacecraft Cassini with an instrument from the Swedish Institute of Space Physics on board (in red circle) passed through Saturn’s atmosphere.
A Langmuir probe, developed in Sweden and flown to Saturn on the Cassini spacecraft, has made exciting discoveries in the atmosphere of the planet. Jan-Erik Wahlund at the Swedish Institute of Space Physics in Uppsala and his colleagues show that there is a strong coupling, both chemically and electrically, between the atmosphere of Saturn and its rings. These research results have now been published in the journal Science.

In April the American space agency NASA put the Cassini spacecraft into an orbit that took it right through the narrow gap between the innermost visible ring (the D-ring) and at the same time very close to the Saturn, so close that it passed through the outer parts of the planet's atmosphere. Cassini made 22 such orbits, and on the 15 September, according to plan, Cassini was sent down into the gas masses of Saturn and burned up. During all of these orbits most of the instruments on board made detailed measurements.

Now the scientific results are starting to take shape, and the results from the Swedish instrument are the first to be published in the well-known journal Science. The instrument, a so-called Langmuir proble, was developed at the Swedish Institute of Space Physics in Uppsala. The upper atmosphere of Saturn is charged and consists primarily of hydrogen and hydrogen ions. The Langmuir probe can be compared with a weather station for electrically charged gas; it measures its density, temperature and velocity. It also measures particles' energy and moreover gives a rough estimate of what the gas consists of.

"The first results are surprising," says Jan-Erik Wahlund, IRF, principle investigator and responsible for the Langmuir probe on Cassini.

Strong variations in density indicate that the electrically charged part of Saturn's atmosphere (the so-called ionosphere) has a strong coupling to the visible rings that consist primarily of ice particles. The ice particles are also electrically charged.

"It is as though the small ice particles in the D-ring suck up electrons from the ionosphere," says Jan-Erik Wahlund. "As a result of the coupling, electrical flows of gas to and from the rings along the magnetic field of Saturn cause the greatest variations in density."

Read more at Science Daily

How much can 252-million-year-old ecosystems tell us about modern Earth? A lot

One of the study's authors, Brandon Peecook, doing fieldwork.
A whopping 252 million years ago, Earth was crawling with bizarre animals, including dinosaur cousins resembling Komodo dragons and bulky early mammal-relatives, a million years before dinosaurs even existed. New research shows us that the Permian equator was both a literal and figurative hotspot: it was, for the most part, a scorching hot desert, on top of having a concentration of unique animals. Here, you could find some of the first tetrapods to emerge from the water and live on land, living right next to newly evolved, dinosaur and crocodile-like reptiles. Many of these species were wiped out after an extinction which changed life on the planet forever.

In a paper published in Earth-Science Reviews, paleontologists studied fossil sites all over the world from the late Permian to get an idea of what lived where. They found an unusual assortment of species near the equator, and one that is comparable to the modern tropics -- except that the array of large, carnivorous reptiles would look very out of place anywhere on Earth today.

"The tropics act as a diversity center -- stuff that has gone extinct elsewhere is still alive there, and there's new stuff evolving," explains Postdoctoral Researcher Brandon Peecook, co-author of the paper. While it makes sense that the warm, wet rainforests we see now have incredible diversity, it seems counterintuitive that these fiery, hot deserts were home to an exceptional range of species, especially because diversity at the equator fluctuates so much historically.

These findings about the late Permian beg the question, "Why are we seeing so much biodiversity at the equator?" This is something scientists have yet to answer, but it shows us that biodiversity at the tropics isn't intuitive, and isn't consistent. What scientists know for sure is that regardless of desert or rainforest, climate change negatively impacts living things.

This unequaled comparison of Permian climate and species distribution to modern events shows us that while many changes are natural and we see them throughout our planet's history, drastic changes like this can be triggered by something much larger -- volcanic activity likely caused this in the Permian, and human activity is the suspected culprit today. After the Permian extinction, "it was almost as though the slate had been wiped clean, and all the ecosystems had to rebuild," says Peecook. This event altered life permanently and while new animals evolved and thrived, the process of recovery took millions of years, and the animals that were lost never returned.

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Life's building blocks observed in spacelike environment

Low-energy electron impact mediates the creation of new complex organic molecules, such as ethanol, in astrophysical/planetary model ices containing methane and oxygen; while some of the new species desorb as ions, many remain in the surface ices.
Where do the molecules required for life originate? It may be that small organic molecules first appeared on earth and were later combined into larger molecules, such as proteins and carbohydrates. But a second possibility is that they originated in space, possibly within our solar system. A new study, published this week in the Journal of Chemical Physics, from AIP Publishing, shows that a number of small organic molecules can form in a cold, spacelike environment full of radiation.

Investigators at the University of Sherbrooke in Canada have created simulated space environments in which thin films of ice containing methane and oxygen are irradiated by electron beams. When electrons or other forms of radiation impinge on so-called molecular ices, chemical reactions occur and new molecules are formed. This study used several advanced techniques including electron stimulated desorption (ESD), X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption (TPD).

The experiments were carried out under vacuum conditions, which both is required for the analysis techniques employed and mimics the high vacuum condition of outer space. Frozen films containing methane and oxygen used in these experiments further mimic a spacelike environment, since various types of ice (not just frozen water) form around dust grains in the dense and cold molecular clouds that exist in the interstellar medium. These types of icy environments also exist on objects in the solar system, such as comets, asteroids and moons.

All of these icy surfaces in space are subjected to multiple forms of radiation, often in the presence of magnetic fields, which accelerate charged particles from the stellar (solar) wind toward these frozen objects. Previous studies investigated chemical reactions that might occur in space environments through the use of ultraviolet or other types of radiation, but this is a first detailed look at the role of secondary electrons.

Copious amounts of secondary electrons are produced when high-energy radiation, such as X-rays or heavy particles, interact with matter. These electrons, also known as low-energy electrons, or LEES, are still energetic enough to induce further chemistry. The work reported this week investigated LEEs interacting with icy films. Earlier studies by this group considered positively charged reaction products ejected from ices irradiated by LEEs, while the work reported this week extended the study to include ejected negative ions and new molecules that form but remain embedded in the film.

The research group found that a variety of small organic molecules were produced in icy films subjected to LEEs. Propylene, ethane and acetylene were all formed in films of frozen methane. When a frozen mixture of methane and oxygen was irradiated with LEEs, they found direct evidence that ethanol was formed.

Read more at Science Daily

Dec 11, 2017

Why meteroids explode before they reach Earth

Our atmosphere is a better shield from meteoroids than researchers thought, according to a new paper published in Meteoritics & Planetary Science.

When a meteor comes hurtling toward Earth, the high-pressure air in front of it seeps into its pores and cracks, pushing the body of the meteor apart and causing it to explode.

"There's a big gradient between high-pressure air in front of the meteor and the vacuum of air behind it," said Jay Melosh, a professor of Earth, Atmospheric and Planetary Sciences at Purdue University and co-author of the paper. "If the air can move through the passages in the meteorite, it can easily get inside and blow off pieces."

Researchers knew that meteoroids often blew up before they reach Earth's surface, but they didn't know why. Melosh's team looked to the 2013 Chelyabinsk event, when a meteoroid exploded over Chelyabinsk, Russia, to explain the phenomenon.

The explosion came as a surprise and brought in energy comparable to a small nuclear weapon. When it entered Earth's atmosphere, it created a bright fire ball. Minutes later, a shock wave blasted out nearby windows, injuring hundreds of people.

The meteoroid weighed around 10,000 tons, but only about 2,000 tons of debris were recovered, which meant something happened in the upper atmosphere that caused it to disintegrate. To solve the puzzle, the researchers used a unique computer code that allows both solid material from the meteor body and air to exist in any part of the calculation.

"I've been looking for something like this for a while," Melosh said. "Most of the computer codes we use for simulating impacts can tolerate multiple materials in a cell, but they average everything together. Different materials in the cell use their individual identity, which is not appropriate for this kind of calculation."

This new code allowed the researchers to push air into the meteoroid and let it percolate, which lowered the strength of the meteoroid significantly, even if it had been moderately strong to begin with.

While this mechanism may protect Earth's inhabitants from small meteoroids, large ones likely won't be bothered by it, he said. Iron meteoroids are much smaller and denser, and even relatively small ones tend to reach the surface.

From Science Daily

Insights on fast cockroaches can help teach robots to walk

Cockroach on a slippery tile.
Using the example of cockroaches, the Cologne-based zoologist Dr Tom Weihmann and his team were able to show that quickly running insects change their gait at mid-speed. This behaviour has previously only been observed in fast mammals. This change in gait is similar to the way horses change from trop to gallop. The results of the study have now been published in the journal Frontiers in Zoology.

'I was particularly surprised that a change in mechanisms stabilizing the animal's movement goes hand in hand with a change in leg coordination', Weihmann notes. An insect's slow run is very stable because its centre of gravity is low and three legs are always moving in a coordinated manner. The research showed that the change in gait at high speed and on a slippery surface was accompanied by a change from static to dynamic stabilization. This minimizes the need of the central nervous system to control the motion while attaining high energy efficiency.

'This discovery not only has far-reaching implications regarding the behaviour and ecology of insects and other arthropodes', says Weihmann. 'Our results can also contribute to solving some problems we still have with the movement of robots.'

Robots with legs generally have better cross-country mobility than robots with wheels. Particularly at high running speeds, however, robots use up a lot of energy -- in contrast to many animals. Thus, the cockroaches' locomotion pattern could contribute to finding a solution that would let robots run at a high speed with an acceptable expenditure of energy. 'Robots with legs that can be used here on Earth after disasters, or on Mars or other planets, are often modelled on insects', Weihmann explains. 'Adapting the coordination patterns of robot legs to those of fast-running cockroaches can help the robot use energy more efficiently and hence increase its endurance in an inhospitable environment.'

The scientists used the organism Nauphoeta cinerea to study its locomotion on slippery and non-slippery surfaces. The results showed that at high speed, the animals reduce the degree to which their legs move in a synchronized manner. This allowed them to avoid disruptions in their coordination or falls even on slippery surfaces.

From Science Daily

Radar tracking reveals how bees develop a route between flowers

A bumblebee eats a food reward presented on an artificial flower. Five such feeders each contain 1/5 of the amount required to fill her up and the bee must learn a route to take her to all five. Visible in the background are a Landrover from which researchers monitor the harmonic radar and a shed which contains the bee’s nest.
As bees gain foraging experience they continually refine both the order in which they visit flowers and the flight paths they take between flowers to generate better and better routes, according to researchers at Queen Mary University of London.

Despite this, bees can be tricked into taking tempting shortcuts between flowers even at the cost of increasing the overall distance they have to fly.

Animals that travel between multiple destinations and return to a home base -- like bees, birds, primates and humans -- face a predicament known to mathematicians as the Travelling Salesman Problem.

The challenge is to find a route that visits each destination while travelling the shortest possible distance. Previous research, looking only at the order in which animals arrive at each destination, has shown that animals often find a good, or even optimal, solution but little is known about how they find that solution.

Lead author Joseph Woodgate, from Queen Mary's School of Biological and Chemical Sciences, said: "Animals cannot simply inspect a map to find out where the best food sources are or plan how to get between them."

Bumblebees start out knowing nothing about the terrain or where they can find food, so they must explore the landscape, discovering locations one by one and then face the challenge of integrating their spatial memories into an efficient route.

"Only by monitoring every move they make as they explore and try to generate a better route, can we understand how they tackle this challenge," Dr Woodgate added.

The researchers allowed bumblebee foragers to feed on an array of artificial flowers and used harmonic radar technology to follow individuals continuously over every foraging trip they made as they gradually developed solutions to the problem of how to visit them all.

The result was one of the largest and most complete datasets on bee flight ever recorded and provided an in-depth look at route development for the first time ever. They found that focussing simply on sequences of visits to feeder stations, rather than the actual movements between stations or the way that routes develop, is insufficient to understand how animals solve route optimisation problems.

The study, conducted in collaboration with Rothamsted Research, was published in Scientific Reports.

Professor Lars Chittka, coordinator of the study, said: "Imagine a salesman from London who needs to call at Manchester, Leeds, Glasgow, Edinburgh and Inverness before returning home. From Manchester it is tempting to make the short trip across to Leeds, and from Glasgow it is tempting to visit Edinburgh, but a salesman who does that will soon find themselves stranded in Inverness with a very long drive home. The better solution is to travel up one side of the UK and return down the other."

The researchers presented the bees with an equivalent challenge.

Dr Woodgate said: "As predicted, our bees showed a strong preference for taking shortcuts between nearby pairs of feeders even though this meant flying further in the long run. However, they did not exclusively fly only to the closest possible feeders, and tried out different routes in a flexible way."

The tracks recorded by the harmonic radar could be used to visualise the routes taken by the bees as they foraged. The researchers developed animated heatmaps that graphically demonstrated how some segments of route became habitual while other explorations were forgotten as preferred flight paths were discovered.

The flight distance and duration of foraging bouts reduced as bees gained experience and this increased efficiency was attributable mainly to experienced bees flying straighter and exploring less, rather than improvements in the order in which flowers were visited.

However, the bees never became completely set in their ways and the researchers uncovered evidence that suggests that they use random processes to introduce some variation into their routes which may help them to try out different visit orders looking for improvements to their routes.

The results also reveal that efficient routes develop by parallel improvements of both the order feeders were visited and the actual movements of bees flying between them. In other words, experienced bees not only visited their feeders in the same order, but also flew along the same flight lines time after time. These habitual flight paths were straighter than the routes they flew when first discovering the feeders, allowing them to reduce their travel distance even when they were unable to visit them in the best possible order.

Read more at Science Daily

Reductions in individual plant growth sometimes boost community resilience

Tomato plants produce repellent chemicals called volatile organic compounds in response to herbivore attacks.
In sports, sometimes a player has to take one for the team. The same appears to be true in the plant world, where reduced individual growth can benefit the broader community.

The findings from the University of Michigan's Paul Glaum and André Kessler of Cornell University help explain the persistence of some plant communities when theory predicts they should go extinct. The work is scheduled for publication Dec. 11 in Nature Communications.

"We looked at how chemical defense cues from plants, meant to deter herbivores, can also deter pollinators," said Glaum, a doctoral student in the U-M Department of Ecology and Evolutionary Biology. "The surprising model result is that while this can lead to fitness losses for individuals, the population effects can be positive for pollinators and plants under some circumstances."

Many plants, including the wild tomato species used in this study, produce chemical compounds to repel insect pests and other hungry herbivores. But those same chemical defenses can reduce the number of visits to the plant by pollinators such as bees, resulting in less pollination of individual plants and decreased growth.

"Biologists have puzzled over how such a costly defense mechanism can be maintained in these plant populations," Glaum said. "How would a plant population with such a strategy persist?"

Glaum and Kessler developed a computer model showing that decreased growth of individual plants can benefit overall populations and community resilience by indirectly controlling herbivore population growth. The results introduce mechanisms of persistence into communities previously found to be prone to extinction in theoretical models.

Tomatoes and other plants produce repellent chemicals called volatile organic compounds in response to herbivore attacks. The presence of these so-called herbivore-induced volatile organic compounds can make the plant less attractive to pollinators, which can reduce pollen deposition and negatively affect individual plants, an effect known as herbivore-induced pollinator limitation.

Previous modeling studies have looked at the direct effects of herbivory on a three-species community: flowering plant, pollinator and herbivore. Some of those studies predicted extinctions because growing herbivore populations would reduce the number of plants, limiting resources available to pollinators. In response, the pollinator population would decline, lowering plant reproduction.

A downward spiral

But Glaum and Kessler reached a different conclusion when they included herbivore-induced pollinator limitation (HIPL) in their model, which allowed them to examine broader, more indirect effects of herbivory on plant population persistence and community dynamics.

"We show that the inclusion of mechanisms like HIPL into models generates the potential for unexpected population and community-level effects that can reduce the tendency for extinction and actually support community persistence," they wrote.

The modeling study suggests that the herbivore-induced release of protective chemical compounds limits population growth of both the pollinator and the flowering plant, thereby temporarily and indirectly restricting the growth of herbivore populations and preventing extinction.

Glaum and Kessler generated the model using data from a series of field experiments on the Pacific slope of the Peruvian Andes conducted by Kessler and his collaborators using the wild tomato species Solanum peruvianum. This plant is subject to attacks by a diverse set of herbivorous insects and is pollinated by wild bees.

The researchers measured both the release of herbivore-induced volatile organic compounds (HI-VOCs) by the wild tomato plants and pollinator visits at different levels of herbivory to determine how bee pollination changes as a function of the amount of herbivory experienced by a plant.

Read more at Science Daily

King Tut's Jewelry and Other Bronze Age Treasures Contain Meteorites

Dagger of Emperor Jahangir, Mughal dynasty, 1621, India. The watered steel blade contains meteoric iron, iron hilt, and a gold inlay.
King Tutankhamun, Mughal Emperor Jahangir, and the legendary King Arthur all had at least one thing in common: They wielded swords made out meteoric iron.

The sturdy metal then and now inspires admiration and awe, given that it is a native metal found in meteorites, which fell from the sky and landed on Earth. It is possible that one of the world's most sacred religious objects, the Black Stone at the Grand Mosque in Mecca, contains the mystical metal, but scientists continue to debate the stone's composition.

New research, however, has just confirmed that multiple Bronze Age artifacts, including King Tut's dagger, bracelet, and headrest, contain meteoric iron. The paper, published in the Journal of Archaeological Science, describes a new geochemical approach for evaluating iron to determine if it was derived from a meteorite or smelting.

In short, the technique can distinguish extraterrestrial from terrestrial iron.

"I show that there is not a single piece of evidence for smelting in the Bronze Age on the one hand, and on the other that all Bronze Age artifacts analyzed properly are made of meteoric iron," author Albert Jambon of the French National Center for Scientific Research, the Sorbonne, and the University of Côte D'Azur told Seeker. "Once they discovered smelting, this is what we call the Iron Age," he continued. "The ability to smelt took some time to propagate from the Near East to north, west, east, and south."

Albert Jambon analyzing a meteorite at Poznan University, Poland
It is not just a novelty then to identify meteorite materials in ancient objects. The research is helping to determine precisely when and where iron smelting first occurred. As Jambon said, "Archaeologists think this happened somewhere in the Near East, sometime about 1200 BC, but we don't know for sure."

The various ages in time named after materials — such as the Stone Age, Bronze Age, and Iron Age — all marked technological advancements that changed the way people made tools, weapons, and dwellings. Just as the Computer Age has changed life as we know it, so too did these different periods affect everything from warfare to cooking.

Since iron smelting requires precise heating and melting of its oxide ore, its emergence marked a great innovation that also affected working with other base metals. The metals that make bronze are more easily recovered from their ores, and the resulting alloy in ancient times was soft enough to be easily worked with tools available then. These properties of bronze led to its namesake age, which lasted from about 3200–500 B.C., depending on the region.

Some historians have claimed that Bronze Age irons were smelted. To investigate the matter, Jambon studied a variety of artifacts containing iron from that time. They included beads from Gerzeh (Egypt, 3200 BC), a dagger from Alaca Höyük (Turkey, 2500 BC), a pendant from Umm el-Marra (Syria, 2300 BC), an axe from Ugarit (Syria, 1400 BC), several items from the Shang Dynasty civilization (China, 1400 BC), and the dagger, bracelet, and headrest of Tutankhamen (Egypt, 1350 BC).

Albert Jambon analyzing Bronze Age artifacts at Poznan University, Poland
Jambon conducted a non-destructive chemical analysis of each item utilizing a portable X-ray fluorescence spectrometer. He determined that the artifacts were made with meteoric iron, which he said has higher levels of nickel and cobalt, and exhibits no signs of having undergone smelting.

While the artifacts all passed the test, Jambon admitted that severely corroded meteorite iron can be difficult to distinguish from smelted iron. The incomplete corrosion of some of the artifacts still permitted analysis of their composition.

Jambon said working with iron from meteors required cold-hammering it or heating it before hammering. Egyptian tablets, he said, mention that metals were "taken from the furnace" before shaped into objects. Gold likely received a similar treatment.

"Bronze Age people were skillful jewelers, using not only gold, but also silver," Jambon said. "Meteorite iron is often associated with gold."

Close-up of an iron-containing meteorite. The surface features numerous thumbprint-like impressions known as regmaglypts that were formed as the meteor passed through Earth's atmosphere.
In fact, the cost of iron during the Bronze Age was ten times that of gold due to its rarity. According to the Meteoritical Bulletin Database, there are only about 1,000 documented records of iron-containing meteorites. Their weights range from 60 tons to less than half an ounce.

"Most of them are 'finds,' meaning that nobody witnessed the falling meteorite, which could be as old as tens of thousands of years," Jambon said.

In the future, he and other scientists hope to be able to link meteoric iron to its source meteors. He is also hoping to better pinpoint when and where the first iron smelting occurred.

Read more at Seeker