Giant plastic ‘berg blocks Indonesian river

A crisis of plastic waste in Indonesia has become so acute that the army has been called in to help.

Rivers and canals are clogged with dense masses of bottles, bags and other plastic packaging.

Officials say they are engaged in a “battle” against waste that accumulates as quickly as they clear it.

The commander of a military unit in the city of Bandung described it as “our biggest enemy”.

Like many rapidly developing countries, Indonesia has become notorious for struggling to cope with mountains of rubbish.

A population boom has combined with an explosive spread of plastic containers and wrapping replacing natural biodegradable packaging such as banana leaves.

The result is that local authorities trying to provide rubbish collection have been unable to keep up with the dramatic expansion of waste generated.

And a longstanding culture of throwing rubbish into ditches and streams has meant that any attempt to clean up needs a massive shift in public opinion.

‘Shocking sight’

In Bandung, Indonesia’s third largest city, we witnessed the shocking sight of a concentration of plastic waste so thick that it looked like an iceberg and blocked a major tributary.

Soldiers deployed on a barge used nets to try to extract bags, Styrofoam food boxes and bottles, a seemingly futile task because all the time more plastic flowed their way from further upstream.

The senior official in charge, Dr Anang Sudarna, who heads the West Java Environmental Protection Agency, told me that the problem was “impossible to sort out without the highest authority”.

That’s why he took the drastic step of appealing to the Indonesian president to send in the army, and the move has made some difference, according to Dr Sudarna.

“The result is a little bit improved…but I am angry, I am sad, I am trying to think how best to solve this… the most difficult thing is the people’s attitude and the political will.”

Frontal assault

For Sergeant Sugito, commanding an army unit, the assignment was new and unusual and “not as easy as flipping your hand”.

“My current enemy is not a combat enemy, what I am fighting very hard now is rubbish, it is our biggest enemy.”

But he also said that plastic should be recognised as valuable – “for example, plastic cartons and drinking bottles can be separated from the other rubbish and sold”, he said.

Encouraging people to see plastic as a resource is a key step towards finding a solution to the crisis.

To encourage recycling, the authorities in the Bandung area are supporting initiatives in “eco-villages” where residents can bring old plastic items and earn small amounts of money in exchange.

The plastics are then divided by type. In one project we visited, two women patiently cut apart bottles and small water cups because separating the different kinds of polymers earns higher prices.

Officials are optimistic that word will spread that plastic has value – and raise awareness of the plastic waste problem – but they also admit privately that many residents are either uninterested or cannot see the point.

Meanwhile, on Bandung’s only landfill site – which receives only a fraction of the waste the city produces – an unofficial form of recycling is under way.

Next generation

On a hillside buried in rubbish, amid an overwhelming stench in the tropical heat, 500 so-called “scavengers” search each new load of rubbish for plastic products.

When I asked one man, scrambling from the path of an excavator, what he was looking for, he reached into a bag and held up a plastic bottle.

The work is punishing but generates income which supports entire families living on the dump, and it also demonstrates that there is a market for recycled plastic and more could be done to serve it.

For one activist working to change attitudes, Mohamad Bijaksana Junerosano of Greeneration, the solution has to involve law enforcement, education and social awareness.

Investment was needed to teach children about waste and recycling, he said, but that had to be done in combination with improvements in public attitudes.

“If we educate the student, when they go outside the school and the ecosystem is still broken and people are littering everywhere, they are confused so it needs both sides, education and also law enforcement by society.”

Monumental scale

A Dutch environmental scientist, Prof Ad Ragas of Radboud University, with long experience of Indonesia’s plastic problem, told me he has detected an important shift in the authorities.

Two years ago, when he organised a workshop on plastic pollution in Bandung, “government officials didn’t seem to care about it, they didn’t see it as a really big problem”.

By contrast, at another workshop held last month, “it’s changed dramatically”.

Social media, rapidly conveying images of choked waterways, had made a difference to people, he said.

“They immediately see that ‘this is what my river look likes now and I’m doing that because I’m throwing all this plastic away’ so they get feedback much quicker than they used to.”

But the challenge is not only monumental in scale; it is also constant.

The soldiers we filmed had planned to load the plastic onto trucks but because the vehicles never arrived they decided on a different course of action: to use a digger to push the waste downstream.

I asked the sergeant what would happen to it. It was up to another unit to collect, he said. It became someone else’s problem.

Near the coast, just outside the capital Jakarta, we came across a canal that was totally blocked with plastic. Local residents complained that whenever they tried to clear it, more arrived from upstream, as in Bandung.

Most apocalyptic of all was the scene at a fishing village on the coast itself. The mud of the shoreline was completely hidden by a thick layer of plastic waste stretching over hundreds of metres.

On a walkway crossing over the sea of plastic was a small girl playing with a balloon. By the time Indonesia’s plastic nightmare is sorted, she may well have grown up.

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Europe’s Mars rover takes shape

So, here it is. Europe’s Mars rover. Or rather, a copy of it.

This is what they call the Structural Thermal Model, or STM. It is one of three rovers that will be built as part of the European Space Agency’s ExoMars 2020 mission to search for life on the Red Planet. And, no, we’re not sending all three to the Red Planet.

The STM is used to prove the design. It will go through a tough testing regime to check the rover that does launch to Mars – the “flight model” – will be able to cope with whatever is thrown at it.

What’s the third robot for? It stays on Earth and is used to troubleshoot any problems. If mission control needs to re-write a piece of software to overcome some glitch on the flight rover, the patch will be trialled first on the “engineering model” before being sent up to the Red Planet.

  • Europe presses ahead with Mars rover
  • Mars probe despatched on methane quest
  • ExoMars rover gets second site option
  • Sky At Night: Mars – Red and Dead?

    It’s getting real, then. After all the delays and arguments, the ExoMars hardware is at last taking shape.

    The STM, which has been assembled at the Airbus factory in Stevenage in the UK, is about to be boxed up and sent to a facility in Toulouse for environmental testing.

    “We’re going to ‘shake and bake’ it to demonstrate that the rover can survive all of the vibrations and acoustic loading during the rocket launch, all of the shocks of deployment, and then all of the thermal stresses it will experience – all the highs and lows – both when it’s in deep space and on the surface,” explained engineer Abbie Hutty.

    “This is where we qualify our design, proving that it meets the requirements.”

    Esa member states will meet on 8 May for the Critical Design Review. This will consider every aspect of the venture and is really the last chance to change some aspect of the mission. There may be some tinkering at the edges, but the broad scope will not alter.

    There have been recent difficulties related to the “Analytical Drawer”, which will hold ExoMars’ life-seeking instruments. A leak was found in the test model for this box and a membrane also failed. “But, OK, this is why you do testing,” said ExoMars project scientist Jorge Vago.

    “Overall, I think we’re on a good track to complete everything we need to do. We have margin. It could be better, but we’re not working double shifts and on weekends, which is what you see on most projects towards the end.”

    ExoMars is a joint venture with the Russians. They’re building the descent module – the mechanism that gets the rover down to the surface once it enters the planet’s atmosphere.

    A structural model of this system is also in production, and when the rover STM completes its Toulouse exams, the two will have a fit check in Moscow and undergo another round of testing as a combined unit.

    A couple of developments in the rover’s capabilities are worth reporting. It’s now been confirmed the robot will be able to wheel-walk.

    This is a driving mode that sees the vehicle lift up its wheels and take steps – as opposed to just rolling forward. It would allow ExoMars to tip-toe out of a sand trap, if it gets caught in one. Nasa’s Spirit rover was snared in this way and the mission lost as a consequence.

    Wheel-walking was in the initial spec for ExoMars and then withdrawn for cost reasons. I’m pleased to report that member states have found the money to put it back on the rover.

    The other key capability that needs a similar response is autonomous navigation. This self-driving system would permit the robot to plot its own path across the surface of Mars, independently avoiding hazards such as large rocks and trenches.

    Without it, controllers back on Earth have to direct every move, and that’s a very slow process.

    “Clearly we need it, otherwise we will pay a high price in terms of the science you can do,” Dr Vago said.

    “To give you an example – if we need to move 500m, with autonomous navigation we can do that in five days. Without it, the drive might take 15 days.”

    Whether the rover gets this smart upgrade is probably going to depend on the UK and French space agencies.

    They’re the parties most interested in the technology and will have to fund it.

    Fortunately, autonomous navigation is a software complement, so even though hardware choices have to be locked down now there is still some extra time to resolve this particular issue.

    If you’re wondering where ExoMars will be sent, the decision will be made in November. Scientists will meet at Leicester University to choose between two equatorial locations, known as Oxia Planum and Mawrth Vallis.

    They’re both areas rich in clay minerals – the kinds of sediments that must have formed during prolonged rock interactions with water. and follow me on Twitter: @BBCAmos

Plastic recycling: Why are 99.75% of coffee cups not recycled?

It’s gradually becoming common knowledge that it’s not as easy to recycle your takeaway coffee cup as people may have thought.

It’s the mixture of paper and plastic in their inner lining – designed to make them both heat and leakproof – that causes difficulties.

There are currently only a small number of specialist plants in the UK able to process the disposable used cups, and as a result, the vast majority of them (more than 99.75%) don’t get recycled.

In 2011 it was estimated that 2.5 billion coffee cups were thrown away each year and that figure is likely to be higher now.

Some of the biggest sellers of coffee in the UK, including Costa and Starbucks, say they have started recycling coffee cups, but that’s only if customers dispose of their takeaway cups in store.

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  • Cup waste: What are coffee chains doing?

    Ace UK, the representative body for beverage carton manufacturers, has 415 recycling points for coffee cups and other paper products across the UK. Cups deposited here will be taken to the company’s own specialist recycling plant.

    They are generally in places like car parks rather than on the street.

    Cups that are left on the kerb in household recycling or in a bin on a high street or railway station, however, will generally end up in landfill.

    Industry body the Paper Cup Alliance says the specialist plants that do have the technology already have the capacity to recycle all the cups we throw away – it’s the infrastructure to transport them there that’s currently lacking.

    A growing number of retailers and offices are buying compostable cups and one of the biggest providers in the UK is Vegware, which makes its products without any plastic so they biodegrade.

    It sells compostable cups to office canteens, schools, hospitals and independent coffee shops and its sales have increased by more than a third in the last two years.

    However, compostable cups have to be disposed of in food waste bins rather than in a normal recycling bin and this is an issue for both homeowners and managers of cafes or workplace canteens.

    Trewin Restorick, at environmental charity Hubbub, believes the right disposable method is not always clear to people and says: “Compostable sounds better, but it can actually make things worse if they are put in the wrong bin.”

    Because they are designed to break down, if they end up in with the plastic recycling they can contaminate it. The same is true if you put an ordinary takeaway coffee cup in the recycling.

    This costs councils money in sorting it and can even lead to the whole batch of recycled items being rejected.

    • Coffee: Who grows, drinks and pays the most?

      Vegware says its products work best in an environment where the waste can be controlled, like a festival. In those kinds of environments people are likely to buy a drink onsite and throw it away onsite.

      The amount of waste that gets rejected for recycling by councils in England has been rising. That waste then ends up in landfills or being burnt.

      The proportion of recycling that gets rejected is still relatively small, though – less than 5%.

      If compostable cups end up in landfill, unlike plastics they will break down. But this misses the opportunity to harness the energy produced through composting for another use – as fertiliser or even to generate electricity.

      Reusable cups

      The three biggest coffee retailers in the UK – Costa, Starbucks and Caffe Nero – all provide incentives for customers to bring in their own reusable mug rather than using a disposable cup.

      Costa and Starbucks offer a 25p discount while Caffe Nero offers double stamps on its loyalty card, which it says is equal in value to 25p.

      Greggs and Pret a Manger – the biggest “food-focused” sellers of coffee according to retail consultancy Allegra Strategies – also have discount schemes. Pret is the most generous with a 50p discount for shunning single-use cups.

      Starbucks has offered a discount for customers in the UK using their own mugs since it opened in 1998, and says about 1.8% of all hot drinks sold are in reusable cups.

      The coffee shop chain is trialling a 5p “latte levy” charge on paper cups in 35 branches in London – a plan proposed on a national level by MPs and rejected by the government in March.

      The trial has been in operation for six weeks so it’s too soon to judge its success, but early indications are that it has increased sales of drinks in reusable cups compared with a discount alone.

      Costa Coffee says about 1% of hot drinks it sells are in reusable mugs and that has been consistent since the discount was introduced.

      The company doesn’t have data on reusable cup use from before the incentive scheme was introduced, so it’s difficult to say whether the discount itself is encouraging some people to use non-disposable cups.

      Caffe Nero don’t have figures on how many drinks are sold in reusable cups because they give extra loyalty card stamps as an incentive rather than discounting the drink itself.

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Wildlife photo competition disqualifies ‘stuffed anteater’ image

A winning entry in the Wildlife Photographer of the Year competition has been disqualified for featuring a taxidermy specimen.

The image, known as The Night Raider, shows an anteater moving towards a termite mound in a Brazilian reserve.

London’s Natural History Museum, which runs the competition, says the use of stuffed animals breaches its rules.

The photographer, Marcio Cabral, denies he faked the scene and claims there is a witness who was with him on the day.

Other photographers and tourists were in the park at the same time and therefore “it would be very unlikely anyone wouldn’t see a stuffed animal being transported and placed carefully in this position”, he told BBC News.

But Roz Kidman Cox, the chair of judges for Wildlife Photographer of the Year (WPY), was stern in her criticism.

“This disqualification should remind entrants that any transgression of the rules and spirit of the competition will eventually be found out,” she said.

The Night Raider picture won the Animals In Their Environment category in the 2017 WPY awards. It was taken in Emas National Park.

The green lights are click beetles hoping to lure termites into being their prey with a bioluminescent display.

The anteater’s appearance was described in the citation caption as being serendipitous – a “surprise bonus” that walked into the shot. But the Natural History Museum (NHM) says third parties recently raised concerns the image was staged – that the hungry interloper is in fact a static model that can be seen at a visitors’ centre at an entrance to the reserve.

When alerted to this possibility, the museum asked five scientists to review the winning photo and to compare it with the centre’s display model.

These experts, who included the NHM’s own taxidermy specialist and South American mammal and anteater researchers, worked independently of each other, but they all came to the same conclusion – that the two animals were one and the same.

The scientists found the markings, the postures, the morphologies and even the positioning of the fur tufts to be just too similar.

Nature’s reality

The NHM says Mr Cabral fully cooperated with the investigation, supplying RAW images for inspection that were taken “before” and “after” the winning scene. But none of these included the anteater.

“Unfortunately, I do not have another image of the animal because it is a long exposure of 30 seconds and ISO 5000,” Mr Cabral said.

“After the flashes were fired, the animal left the place, so it was not possible to make another photo with the animal coming out of the place that is totally dark.”

The WPY rules state that “entries must not deceive the viewer or attempt to misrepresent the reality of nature”. And it is on this basis that The Night Raider has been stripped of its title and removed from display in the competition’s UK tour.

Roz Kidman Cox has been a judge on WPY for more than 30 years. She told the BBC: “I find it disheartening and surprising that a photographer would go to such lengths to deceive the competition and its worldwide following.

“The competition places great store on honesty and integrity, and such a breach of the rules is disrespectful to the wildlife-photography community, which is at the heart of the competition.”

Iberian wolf

This is not the first time the WPY judges have had to disqualify a winning entry. In 2009, they threw out the grand prize photo that supposedly depicted a wild Spanish wolf jumping over a gate.

A similar investigation concluded that the pictured animal was not wild at all, but a tame wolf from a zoo.

Ms Kidman Cox said the judges were always alert to the possibility that photos might be staged but that the artifice could be very hard to spot if the featured animals were in a natural pose in a low-lit scene.

“The judges themselves are chosen to include a range of skills and expertise, both biological and photographic, and are well able to question the veracity of an image,” she added.

“The rules also make it clear that the competition champions honest and ethical photography, and they are translated into a number of languages to prevent any misunderstanding.”

Mr Cabral describes his exclusion as a sad decision and one he will continue to contest.

The visitors’ centre is locked at night and has guards and so he could not have had access to the model, the photographer says. He intends to return to Emas National Park later this year to collect evidence that he believes will exonerate him. and follow me on Twitter: @BBCAmos

Closing gender gap in physics ‘will take generations’

Closing the gender gap in physics will take hundreds of years, given the current rate of progress.

That’s the finding of research analysing the names of authors listed on millions of scientific papers.

Physics, computer science, maths and chemistry had the fewest women, while nursing and midwifery had the most.

Without further interventions, the gender gap is likely to persist for generations, said scientists from the University of Melbourne.

“Of the gender-biased disciplines, almost all are moving towards parity, though some are predicted to take decades or even centuries to reach it,” said Dr Cindy Hauser.

Number crunching

The researchers used computer methods to analyse the genders of authors listed in databases (PubMed and ArXiv) containing thousands of scientific papers published over the past 15 years.

They found that 87 of the 115 subjects examined had fewer than 45% women authors.

Women are increasingly working in male-biased fields such as physics (17% women), while men are increasingly working in female-biased fields such as nursing (75% women).

However, forecasts suggest it will take a very long time to close the gender gap in some fields, with predictions of 320 years for nursing, 280 years for computer science, 258 years for physics and 60 years for mathematics.

The researchers said practical measures are already known that could help close the gap, including:

  • Reforming publishing
    • Ensuring women receive equal resources at work
      • Greater recognition of demands outside the workplace that traditionally fall on women when assessing achievements
        • Better access to parental leave and career breaks
          • Equal access to informal professional networks.

            “The solutions are out there but it’s difficult to bring about change and get people to act on them,” said Dr Luke Holman.

            “We haven’t acted on them enough because it’s difficult to change the way that people have always done things and it’s maybe not afforded as high a priority as it should be by people in positions of power in the scientific industry and academia.”

            The researchers also looked at variation across countries.

            They found a larger gender gap in Japan, Germany and Switzerland and a smaller gender gap in some European, African and South American countries.

            The research is published in the journal PLOS Biology.

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Plankton named after BBC Blue Planet series

A type of plankton described as part of “the beating heart” of the oceans has been named after the BBC’s Blue Planet series.

The tiny plant-like organism is regarded as a key element of the marine ecosystem.

Scientists at University College London (UCL) bestowed the honour on Sir David Attenborough and the documentary team.

It’s believed to be the first time a species has been named after a television programme.

A single-celled algae, the plankton was collected in the South Atlantic but is found throughout the world’s oceans.

It will now be officially known as Syracosphaera azureaplaneta, the latter translating from the Latin as ‘blue planet’.

Sir David received the honour during a visit to UCL to open the newly refurbished Earth Science department, he said it was “a great compliment” and he was delighted that it would help raise awareness of the importance of plankton to the oceans.

“If you said that plankton, the phytoplankton, the green oxygen-producing plankton in the oceans is more important to our atmosphere than the whole of the rainforest, which I think is true, people would be astonished.

“They are an essential element in the whole cycle of oxygen production and carbon dioxide and all the rest of it, and you mess about with this sort of thing and the echoes and the reverberations and the consequences extend throughout the atmosphere.”

The Blue Planet plankton is only about 10 microns across – the diameter of a typical human hair is about seven times greater.

It only lives for a few days but in that brief time creates shapes of incredible intricacy and beauty.

Looking at microscope images of the plankton, Sir David joked: “I’m not sure about the likeness but it’s lovely… they’re stunning, they’re beautiful.”

About a dozen different species have been named after the naturalist and presenter himself – including a rare tropical butterfly, a flightless Indonesian weevil and an armoured prehistoric fish whose fossil was found in Western Australia.

Others have been named in honour of celebrities – a horse fly after the singer Beyonce, a lemur for comedian John Cleese and a tree frog after Prince Charles.

Brazilian scientists named a bee after a catchphrase from a TV show.

But the Blue Planet plankton is thought to be the first example of a species given its name out of respect for a documentary series.

James Honeyborne, executive producer of Blue Planet 2, said: “Phytoplankton may be tiny but they are the basis of all life in the ocean – feeding everything from baby fish to great whales – and they help keep our seas, and indeed our whole planet healthy.

“It’s a great honour for everyone in our wider Blue Planet II team: our filmmakers, camera operators, associated scientists and conservationists, explorers and support teams, to be associated with such an impactful form of life.”

Prof Paul Bown of UCL said plankton played a vital role in the ocean, supporting the lives of much better known creatures.

“In terms of the link to the Blue Planet series, we felt they were the unseen stars of the series – hidden in plain view because of their minuscule size – but representing the beating heart of the oceans, providing food and pumping carbon from the shallow ocean to the deep-sea,” he said.

He also said that because they create a hard covering “they form a constant rain of carbonate to the seafloor and form oceanic deep-sea ooze”.

That allows scientists to study an “archive” of information locked in layers of rock on the sea floor.

“We therefore have an amazingly complete fossil record stretching back 220 million years to the Triassic,” Prof Bown said, which allows scientists to study major upheavals in the past such as extinction events.

As he leant towards an image of the Blue Planet plankton, Sir David said admiringly: “Why that’s not made by a modern jeweller I have no idea…”

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EU member states support near-total neonicotinoids ban

Member states have voted in favour of an almost complete ban on the use of neonicotinoid insecticides across the EU.

Scientific studies have long linked their use to the decline of honeybees, wild bees and other pollinators.

The move represents a major extension of existing restrictions, in place since 2013.

Manufacturers and some farming groups have opposed the move, saying the science remains uncertain.

Neonicotinoids are the most widely used class of insecticides in the world, but concerns about their impact on bees have been reinforced by multiple research efforts, including so-called “real world” trial results published last year.

Change of heart

Back in 2013 the European Union opted for a partial ban on the use of the three chemicals in this class: Imidacloprid, clothianidin and thiamethoxam.

The restrictions applied to crops including maize, wheat, barley, oats and oil seed rape. The newly agreed Commission regulation goes much further, meaning that almost all outdoor uses of the chemicals would be banned.

Voting on the proposal had been postponed a number of times as countries were split on the move. However, Friday’s meeting saw a qualified majority vote in favour of the ban.

The action has been driven by a recent report from the European Food Safety Authority (Efsa), which found that neonicotinoids posed a threat to many species of bees, no matter where or how they are used in the outdoor environment.

“The Commission had proposed these measures months ago, on the basis of the scientific advice from the European Food Safety Authority,” said EU Commissioner for Health and Food Safety, Vytenis Andriukaitis.

“Bee health remains of paramount importance for me since it concerns biodiversity, food production and the environment.”

Another key element that helped push the vote through was the UK’s change of heart on the use of these insecticides. Environment Secretary Michael Gove announced last November that Britain would now support further restrictions.

“I think it has helped the dynamic,” Franziska Achterberg from Greenpeace told BBC News.

“It has helped sway Ireland definitely, and then lately, the Germans, the Austrians and the Dutch. I think the fact the UK had come around was a good signal for them as well, that they could not stay behind.”

Growers will only be free to use neonicotinoids in greenhouses across the EU, despite some environmental groups having reservations about the chemicals leaching into water supplies. Other neonicotinoids, including thiacloprid and sulfoxaflor, will continue to be exempt from the ban.

Environmental campaigners have welcomed the ban. Some five million people around the world had signed petitions calling for an extension of restrictions.

“Banning these toxic pesticides is a beacon of hope for bees,” said Antonia Staats, from Avaaz,

“Finally, our governments are listening to their citizens, the scientific evidence and farmers who know that bees can’t live with these chemicals and we can’t live without bees.”

No benefits for bees

Many farmers are unhappy about the increase in restrictions, saying they do not believe they are warranted on scientific grounds and that the existing partial ban has not delivered results.

“The Commission hasn’t been able to find that these restrictions have delivered any measurable benefits for bees,” said Chris Hartfield from the National Farmers’ Union (NFU) in the UK.

“That has been a big question for us, and if we can’t be certain they can deliver measurable benefits why are we doing this?”

The new regulation will be adopted in the coming weeks and will be applicable by the end of the year. Some farmers believe it will have significant impacts on the types of crops grown across the Continent.

“The irony of the current restrictions is that it has led to the decline of oil seed rape being grown in the UK and that’s reflected across the whole of Europe,” Mr Hartfield said.

“We’re not decreasing our consumption of that product; we are just importing it from outside Europe, where it is often treated with neonicotinoids. I would expect to see that continue.”

Some campaigners believe that the extended ban heralds a new era for EU farmers where the needs of the environment are seen as more important than production.

“It’s a significant indication that we need a different form of farming across Europe that farms with nature and not against it,” said Sandra Bell from Friends of the Earth.

“The ban on neonicotinoids could be a really important step towards a more general questioning of the use of pesticides and the harm they are doing to our environment.”

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How ancient DNA is transforming our view of the past

Prof David Reich of Harvard Medical School is one of the leading lights in the field of ancient DNA. His team’s work has cast a new perspective on human history, reconstructing the epic migrations and genetic exchanges that shaped the people of different regions worldwide. Here he explains how this revolution in our understanding unfolded.

If it seems as if there has been an avalanche of recent headlines revealing insights into the travails of our ancient ancestors, you’d be right.

From the fate of the people who built Stonehenge to the striking physical appearance of Cheddar Man, a 10,000-year-old Briton, the deluge of information has been overwhelming.

But this step change in the understanding of our past has been building for years now. It’s been driven by new techniques and technological advancements in the study of ancient DNA – genetic information retrieved from the skeletal remains of our long-dead kin.

At the forefront of this revolution is David Reich of Harvard Medical School in Boston Massachusetts. I met Prof Reich recently at the BBC while he was in the UK to talk about his book Who We Are and How We Got Here, which draws together the most recent scientific results in this field of study.

The Harvard professor, who is 43, was recently highlighted by the journal Nature as one of 10 people who mattered in all of science for his role in transforming the field of ancient DNA from “niche pursuit to industrial process”.

Reich was raised in Washington DC, by parents who were distinguished in their own fields. His mother Tova is a novelist and his father Walter is a professor of psychiatry who also served as the first director of the United States Holocaust Memorial Museum.

“In my family, there was a premium and a strong belief placed on creativity – doing something new and interesting and edgy. Science was seen as the highest thing someone could do,” he says. “I had lots of interests, but the things I was most interested in were history and science.”

Reich says that he “fell in love” with human evolutionary history at the beginning of his PhD in biochemistry, but then moved away from the subject towards medical genetics. He explained: “The technology at the time really wasn’t very good for learning a lot about human history.”

Throughout the 1990s and early 2000s, studies of ancient DNA from our own species were highly contentious because of observations that skeletal remains were easily contaminated by the DNA of living people.

As such, there were always nagging doubts about whether a genetic sequence belonged to the long-dead individual being studied or to an archaeologist involved in excavating the remains, a museum curator who had handled them, or a visitor to the lab where they were being analysed.

However, crucial progress in overcoming these obstacles began in the late 90s with the effort to sequence DNA from Neanderthals, which was led by Professor Svante Pääbo at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

Pääbo’s group developed a set of protocols to prevent contamination slipping through, including having the same samples sequenced in two laboratories by different teams.

But the field experienced a revolution with the emergence of so-called next-generation sequencing technology. When an organism dies, the DNA in its cells begins to break down – over time it splits into smaller and smaller chunks, as well as accumulating other forms of damage.

It also gets contaminated with vast amounts of microbial DNA from the wider environment. The new sequencing machines could be used to isolate the human genetic material from bacterial DNA and then stitch together the tiny fragments into a readable sequence.

In 2006, Reich and his close scientific collaborator Nick Paterson were invited by Svante Pääbo to join the Neanderthal genome effort. Pääbo had been particularly impressed by a Nature paper they had authored on the complex separation of the human and chimpanzee evolutionary lineages, and thought the techniques they had used would be relevant to the question of whether Neanderthals and modern humans had interbred.

“I was working on the last 10,000 years of human history, reconstructing it on the basis of present-day people, especially in India… it was obvious the ancient DNA techniques that worked in Neanderthals were going to work even better in more recent humans,” Reich explains.

“I talked to Svante and he said: ‘This is very important but it’s not my focus. I’m focused like a laser beam on archaic humans and early modern humans.'”

Reich took a radical decision to completely re-tool his laboratory at Harvard – which had been focused on medical genetics – along the lines of Pääbo’s lab in Leipzig.

“There was a scientist in my laboratory, Nadin Rohland, who had worked in Leipzig (with Svante Pääbo) who knew how to do everything… they helped us to establish this laboratory. It was a big bet that this was a good thing to do.”

The bet paid off in a major way. Reich used his next-generation sequencing tech to power through genome after genome. To date, the lab has retrieved DNA from more than 900 ancient individuals.

The results are helping assemble new narratives for the peopling of our world. In some cases, the results have forced archaeologists and historians to re-visit some long-held ideas, sparking no small amount of debate and controversy.

Reich’s team has helped unravel the tangled web of migration and interbreeding that set down the present-day genetic landscape of Europe. Archaeologists had long suspected that the spread of farming out of the Near East and across Europe was a formative event in the continent’s prehistory.

Reich’s work helped confirm that this meeting of rather distantly related Near East farmers and indigenous hunter-gatherers had been crucial to the mix of ancestry that characterises Europeans, but his team added a third key ingredient to the melting pot.

In a paper published in the journal Genetics in 2012, Reich and his colleagues had spotted that Northern and Central Europeans appeared to have received genetic input from a population related to Native Americans.

Further evidence from ancient DNA would confirm that this distinctive genetic signature had entered Europe for the first time during a mass migration of people from the steppe, on Europe’s eastern periphery.

These nomadic steppe pastoralists, known as the Yamnaya, moved west in the late Neolithic and Bronze Age, around 5,000 years ago. In some areas of Europe, they replaced around 75% of the ancestry of existing populations.

Theories of large-scale migrations had fallen out of favour over the years among some scholars, particularly those for whom the phrase “pots, not people” (that culture tends to spread via the exchange of ideas rather than large-scale movement) had become a mantra.

But successive papers from the Reich group and other teams working on ancient DNA, such as the one led by Eske Willerslev at the University of Copenhagen, showed that mass migrations, with the displacement of earlier populations, were not uncommon in history.

This year, Reich’s team published a sprawling study detailing how an archaeological culture known as the Beaker phenomenon transformed the genetic make-up of western and central Europe. In Britain, the Beakers replaced an astonishing 90% of the existing ancestry. The team isn’t finished with Britain, Reich is now planning to track changes that occurred in the Iron Age and Roman period.

Conflict, innovations such as horse riding, and the spread of diseases like plague to populations with naïve immune systems might all have played a role in some dispersals.

But the reasons behind these replacements remain a question for archaeologists, says Reich. “I think we’re providing data and it vividly portrays the magnitude of these events. Understanding why it happens is a little bit hard for me to say,” he explains.

Reich says that his collaborator Nick Paterson’s background in mathematics has been “absolutely critical” to teasing out the genetic relationships that underlie many key discoveries.

“My laboratory has two lab heads not one, the other is Nick Paterson. I’m not a serious mathematician: I’m numerate, a data analyst, but not a developer of techniques. Nick is a world class mathematician.”

Paterson has an extraordinary biography. Born in 1947 to Irish parents in London, his talents made him a child maths and chess prodigy. A few years after graduating from Cambridge University, he was recruited to work for the UK’s signals intelligence agency GCHQ, where he spent a decade.

After that, he worked for another 10 years at the US equivalent, the National Security Agency (NSA). After leaving the spy world, Paterson worked for the successful New York-based hedge fund Renaissance Technologies, before beginning his collaboration with Reich in 2001.

In the last few years, the Harvard team has also published studies on ancient DNA from Africa, the Middle East and Oceania. Reich is currently finalising a paper on the peopling of South Asia – a longstanding area of interest – which should get published this year. It is likely to be pored over in India, where notions of deep-rooted ancestry are linked to Hindu nationalism.

The Harvard professor recently penned an opinion piece in the New York Times which stirred controversy online, highlighting the lack of consensus on how to frame discussions of human biological variation. In his article, Reich comments: “It is important, even urgent, that we develop a candid and scientifically up-to-date way of discussing any such differences, instead of sticking our heads in the sand and being caught unprepared when they are found.” Some 67 researchers signed an open letter (published by Buzzfeed), objecting to arguments put forward in the op-ed.

For example, the letter says: “Reich critically misunderstands and misrepresents concerns that are central to recent critiques of how biomedical researchers – including Reich – use categories of ‘race’ and ‘population'”.

The researchers add: “This doesn’t mean that genetic variation is unimportant; it is, but it does not follow racial lines. History has taught us the many ways that studies of human genetic variation can be misunderstood and misinterpreted.”

Asked about the criticisms, the Harvard professor told me: “I’m actually very pleased to be part of introducing this discussion. I think that scientists have been anxious about discussing differences among populations in public fora, even though all the work that we do is about differences among populations and learning about their history. The anxiety is about possible misuse of that data – for good reason.”

He stressed the need for scientists to take charge of the narrative, lest they hand the initiative to those with less benign intentions. “The thing I have felt very strongly, increasingly over time, is that the fact that scientists are too afraid to speak up about these topics means that the vacuum… gets filled by people who don’t really know the scientific facts,” he explains.

Prof Reich says that science itself shouldn’t be considered immune from the influence of longstanding assumptions. “I think there’s a huge opportunity for interpretational bias. I think that the genetic data are very seriously constraining the models that are possible right now,” he says.

But, he adds: “There’s some advantage to coming at it from the outside… arguably, there’s something to be said for a non-Jewish European person studying Jewish population history, or a person from Africa studying East Asian population history… in my lab, I’ve pushed people to work on areas that are not their own background.”

Looking to the future, Prof Reich sees huge potential for uncovering as yet unknown human movements and gene exchange in different parts of the world.

“I think Africa is a place that’s deeply under-represented. There are maybe only 20 genome sequences in what is the most diverse place in the world – the place with the deepest and most complex human history,” said Prof Reich.

“That compares to more than 1,000 genomes from Europe right now, which is an important but small corner of the world.”

He adds: “There’s so much to do.”

Follow Paul on Twitter.

Who We Are and How We Got Here by David Reich is published by Oxford University Press.

‘Ground-breaking’ galaxy collision detected

Scientists have detected a cosmic “pileup” of galaxies in the early Universe.

Imaged almost at the boundary of the observable Universe, the 14 unusually bright objects are on a collision course, set to form one massive galaxy.

This will in turn serve as the core for a galaxy cluster, one of the most massive objects in the Universe.

The catch? This all happened over 12 billion years ago.

Looking this far across the Universe is essentially looking back in time, as the light has taken many billions of years to reach us.

The galaxies would have been in their observed configuration when the Universe was a mere 1.4 billion years old.

  • Ghost galaxy prompts cosmic mystery
  • Dozen black holes at galactic centre
  • Signal detected from cosmic dawn

    Originally detected in a wide sky survey using the South Pole Telescope, the objects surprised astronomers as they were clustered so close together.

    “We found it originally as a bright point source in the survey,” explained Yale University’s Tim Miller, an author on the study published in Nature.

    “I don’t think we were expecting something quite this spectacular but we knew it had to be exciting.”

    Star nurseries

    Known as starburst galaxies, the objects are extremely bright as they are forming stars at a high rate – up to 1,000 times as fast as the Milky Way.

    Professor Caitlin Casey, who was not involved in the study, described the findings as “extremely unusual.”

    “We often get excited when we find just two galaxies like this grouped together, because each one is already quite unusual and rare compared to ‘normal galaxies’, forming stars several hundreds or thousands of times faster than the Milky Way. To find fourteen such starbursts all grouped together is unheard of,” the University of Texas at Austin researcher commented.

    Crowded neighbourhood

    The group occupy a region of space just four or five times the size of the Milky Way, making it incredibly dense.

    “If you put all the planets into the orbit between the Earth and Moon, it’s the same sort of scale of mass concentration,” explained Dr Axel Weiß, a co-author on the study.

    The question of why such a concentration of galaxies was able to evolve in this location, and so early in the Universe’s history, remains unanswered for now.

    “This is just so early. This is before the peak of star formation,” says Miller.

    A long way to here

    So what have these galaxies gotten up to in the intervening billions of years?

    By now, models predict that they would have coalesced to form the core of an even more massive cluster.

    Miller explains that in the present day, astronomers expect the structure would be as massive as the Coma Cluster.

    Stretching across two degrees of the night sky, or over four times the visible space occupied by the full moon, the Coma Cluster is truly a giant.

    “The uniqueness of the Coma Cluster is it’s one of the most massive structures we know about in the whole local Universe. [It has about] 10,000 billion solar masses. It’s the most extreme structure that we know about,” explained Dr Weiß.

    Thus far, very few of these large galaxy clusters have been detected, but work continues on further candidates.

    Dr Weiß, who was involved in another study which revealed a similar cluster of ten galaxies, says that there are some other candidates.

    “[Though] these are certainly the most extreme ones,” said the Max Planck Institute for Radio Astronomy scientist.

    Dr Amy Barger, from the University of Wisconsin-Madison found the work to be “ground-breaking.”

    “Finding the progenitors of present-day massive clusters has always been of great importance for piecing together when and how structure grows in the Universe,” she told BBC News.

Gaia telescope’s ‘book of the heavens’ takes shape

The Gaia observatory has released a second swathe of data as it assembles the most precise map of the sky.

The European Space Agency telescope has now plotted the position and brightness of nearly 1.7 billion stars.

It also has information on the distance, motion and colour of 1.3 billion of these objects.

Gaia’s “book of the heavens” will not be complete until the 2020s, but when it is the map will underpin astronomy for decades to come.

It will be the reference frame used to plan all observations by other telescopes. It will also be integral to the operation of all spacecraft, which navigate by tracking stars.

But beyond that, Gaia promises a raft of new discoveries about the properties and structure of our Milky Way Galaxy, its history and evolution into the future.

It will enable scientists to find new asteroids and planets; and to test physical constants and theories.

Gaia should even refine the techniques used to measure distances across the wider Universe, and reduce the uncertainties we currently have about the age of the cosmos.

  • Europe selects grand gravity mission
  • Gaia clocks speedy cosmic expansion

    Gaia was launched in December 2013 to an orbit some 1.5 million km from Earth.

    Its two identical telescopes throw their captured light on to a huge, one-billion-pixel camera detector connected to a trio of instruments.

    A first tranche of measurements was released in 2016. This contained the position and brightness of “just” 1.1 billion stars, and information on the distance and motion of the two million brightest objects.

    This second data release adds 600 times more stars with distances, covering a volume 1,000 times larger and all with precisions that are 100 times better.

    “This is a unique moment,” said leading British Gaia scientist Prof Gerry Gilmore. “This is the first time that mankind has had a significant 3D map of a significant volume of the Milky Way. It really is a breakthrough moment,” he told a meeting at the Royal Astronomical Society in London.

    Gaia: How far is it to the nearest stars?

    • As the Earth goes around the Sun, relatively nearby stars appear to move against the “fixed” stars that are even further away
    • Because we know the Sun-Earth distance, we can use the parallax angle to work out the distance to the target star
    • But such angles are very small – less than one arcsecond for the nearest stars, or 0.05% of the full Moon’s diameter
    • Gaia will make repeat observations to reduce measurement errors down to seven micro-arcseconds for the very brightest stars
    • Parallaxes are used to anchor other, more indirect techniques on the ‘ladder’ deployed to measure the most far-flung distances

      Gaia measures anything that moves – which is actually everything that is out there.

      It sees stars’ “proper motion”, which is their general track across the heavens as they orbit the galaxy. The telescope also sees their “parallax” – their apparent looping behaviour, which is a function of Earth and Gaia changing their vantage point as they circle the Sun (It is the parallaxes that yield the distances).

      And what Gaia also sees is the stars’ movement along its line of sight – their so-called “radial velocity”, their true motion on the sky. Gaia delivers this data for the first time in the new release.

      “We now have seven million line-of-sight velocities of stars which is more than all other measurements ever done. This is a huge sample compared with the few hundred thousand that we had before,” said Prof Mark Cropper, from the Mullard Space Science Laboratory, University College London.

      It is the radial velocities that allow researchers to make movies of the Milky Way, to run its life forwards and backwards in time, to determine, with the aid of other Gaia information, where stars were born and where they will likely end their days. It should be possible, for example, to find our Sun’s siblings – the stars that were created in the same gas and dust cloud billions of years ago but then subsequently went their different ways.

      There will be another two big data releases in the coming years. The more Gaia works, the more precise its measurements – and the more objects it will detect. There is an expectation, for instance, that tens of thousands of planets will eventually be found in Gaia’s data.

      The scale of the venture means there is too much information for professional astronomers to scrutinise, and amateurs and schools are being asked to get involved.

      An alert system operates that throws up interesting objects that brighten or dim out of the ordinary. Some of these will be exploding stars – supernovae.

      Many UK schools are now engaged in classifying these objects.

      Meg Greet, a physics teacher from Eastbury Community School in the London Borough of Barking & Dagenham, said Gaia was a fantastic educational tool: “These long-term embedded enrichment projects, rather than school trips and one-off activities, are the things that make a genuine impact on our school-children scientists, helping them to develop their creativity, their questioning skills – the kind of things they need to become the scientists of the future.”