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Scientists Just Discovered 3 New Kinds of Carnivorous Sponge in The Deep Ocean

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Even though we know the deep sea is weird, ‘carnivorous sea sponges’ still sound like something from a sci-fi movie. And yet, researchers just announced the discovery of three new such species off the coast of Australia.

 

Go a few hundred metres deep into the ocean, and it starts to look like you’re in a whole new world: From a creature that looks like a sea star crossed with an octopus, to shark-devouring fish, to carnivorous sponges we’ve never seen before.

“It just goes to show how much of our deep oceans are yet to be explored – these particular sponges are quite unique in that they are only found in this particular region of The Great Australian Bight – a region that was slated for deep sea oil exploration,” said one of the researchers, Queensland Museum Sessile Marine Invertebrates Collection manager Merrick Ekins.

Typically, sea sponges are multicellular filter feeders – they have holey tissues for flowing water, from which their cells extract oxygen and food. They’re pretty simple creatures, with no nervous, digestive, or circulatory system, but have existed in some form for over 500 million years.

SAM S2599 MOD 2Scanning electron microscope image of Abyssocladia oxyasters. (Ekins et al., Zootaxa, 2020)

But carnivorous sponges are a bit different. Some carnivorous sponges still use the water flow system, while others (like the three newly discovered species) have lost this ability altogether, and nab small crustaceans and other prey using filaments or hooks.

The researchers in this study found three new species of carnivorous sponges – Nullarbora heptaxia, Abyssocladia oxyasters and Lycopodina hystrix, which are also all new genera, as well as a closely related species of sponge that isn’t carnivorous, Guitarra davidconryi. All these species were found at depths of between 163 and over 3,000 metres (535 to 9,842 feet) deep.

 

“Here we report on an additional four new species of sponges discovered from the Great Australian Bight, South Australia. This area has recently been surveyed, using a Smith-McIntyre Grab and a Remotely Operated Vehicle (ROV) to photograph and harvest the marine biota,” the researchers write in their new paper.

“These new species are the first recorded carnivorous species from South Australia and increase the number of species recorded from around Australia to 25.”

The sponges are also prettier than you would imagine, looking a little like flowers with their spiky protrusions, but not a lot like sponges. 

SAM S2599 MOD 3Close up of A. oxyaster. (Ekins et al., Zootaxa, 2020)

Carnivorous sponges are having a bit of a moment. We’ve known about them since 1995, but many more have recently been discovered around the world.

“Over the past two decades, our knowledge of carnivorous sponge diversity has almost doubled,” the same team explains in an earlier paper, where they described their discovery of 17 new species of carnivorous sponges.

“[This is] due in part to rapid advances in deep sea technology including ROVs and submersibles able to photograph and harvest carnivorous sponges intact, and also to the herculean efforts of a number of contemporary taxonomists redescribing many of the older species described in the 19th and 20th centuries.”

Nearly every species of carnivorous sponge found in Australia was discovered during a CSIRO RV Investigator Voyage in 2017, showing just how important these deep-sea investigations are.

With the bottom of the ocean still mostly unexplored, we imagine we’ll see plenty more species of carnivorous sponges, and other weird and wonderful sea creatures. 

The research has been published in Zootaxa.

 



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Octopuses May Be Adapting to The Rising Acidity of Our Oceans, Study Suggests

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We know that all the excess CO2 we’re pumping into the air – alongside a host of other damaging effects – is driving up the acidity of the oceans as it sinks and dissolves into the water, but it seems as though the hardy octopus can find ways to adapt to its rapidly changing environment.

 

Previous research into the impact of ocean acidification on cephalopods such as octopuses, cuttlefish, and squid has shown some indication increased carbon dioxide in the water could negatively impact this type of marine life.

However, in a new study, a group of Octopus rubescens – a species of octopus common to the west coast of North America – were observed adjusting their routine metabolic rate (RMR) over a series of weeks in response to lowering pH levels in the surrounding water.

“Challenges to an organism’s physiology are often reflected in changes in energy use and therefore can be observed as changes in aerobic metabolic rate,” write the researchers in their paper.

A total of 10 octopuses were studied under controlled lab conditions, with RMR measured immediately after exposure to acidic water, after one week, and after five weeks. Critical oxygen pressure – a measure of whether not not animals are getting enough oxygen – was monitored at the same time.

To begin with, high levels of metabolic change were detected in the creatures – a sort of shock reaction that actually conflicts with earlier research into cephalopods, which had recorded a reduction in metabolic change in similar scenarios.

 

However, RMR had returned to normal after one week, and remained the same five weeks later, suggesting some adaptation had occurred. The increased acidity did have an impact on the ability of the octopuses to function at low oxygen levels, however.

“This response in RMR suggests that O. rubescens is able to acclimate to elevated CO2 over time,” write the researchers. “The observed increase in RMR may be the result of multiple acute responses to hypercapnia [increased CO2 in the blood], possibly including both behavioural and physiological strategies.”

Those strategies could include preparing to move to find a new stretch of water to inhabit, for example, the researchers suggest (something that wasn’t possible here). The short RMR boost might also reflect the octopuses making quick adjustments to their biological processes to suit the new acid level.

The study is the first to look at both short-term (one week) and longer-term (five week) changes in metabolism rates in cephalopods in response to ocean acidification. We know these creatures are tough, and it seems they even have coping strategies that might allow them to adapt to humans destroying the natural environment all around them.

None of this means that we should be okay with the current climate crisis though, or not be trying to make major changes to reverse it. When we don’t take proper care of the planet, it’s not just ourselves that we’re potentially dooming to extinction.

Also, these tests were done in controlled laboratory conditions that don’t take into account many other interlinking factors in the animals’ natural environment. For instance, even if the octopus themselves are able to adjust, what about their food supply?

“While this species may be able to acclimate to near-term ocean acidification, compounding environmental effects of acidification and hypoxia may present a physiological challenge for this species,” write the researchers.

The research has been published in Physiological and Biochemical Zoology.

 



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Scientists May Have Finally Found a Key Mechanism Behind Irritable Bowel Syndrome

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It can begin with abdominal pressure from a bloating belly. This can escalate into cramping pain and nausea. Or, a sudden urge to flee to the toilet right now

These uncomfortable, disruptive and, at times, embarrassing symptoms are all too familiar for up to one in five people who, like me, have misbehaving gastrointestinal systems.

 

Conditions like irritable bowel syndrome (IBS) are more common in women. Their triggers can include poor sleep, stress, or simply eating the wrong, seemingly benign food. You can eat what would be, by every other measure, an extremely healthy meal and end up feeling like you’ve just been food poisoned. 

Until my diagnosis, I would never have thought something as innocuous as an apple could cause such a dramatic bodily reaction as explosive diarrhoea.

While carefully maintaining a low FODMAP diet has provided me and many others with some desperately needed relief and control over our symptoms, the physiological mechanism behind our suffering has remained a mystery. This can make receiving a clear and timely diagnosis challenging.

“Very often these patients are not taken seriously by physicians, and the lack of an allergic response is used as an argument that this is all in the mind, and that they don’t have a problem with their gut physiology,” said Katholieke Universiteit Leuven gastroenterologist Guy Boeckxstaens, whose team of more than 40 researchers, led by neuroimmunologist Javier Aguilera-Lizarraga, have just identified a biological mechanism behind IBS. 

 

“With these new insights, we provide further evidence that we are dealing with a real disease.”

Clinical studies have suggested gut infections from pathogens like Escherichia coli, and Salmonella can increase the likelihood of someone developing IBS and patients often describe their symptoms commencing after a case of food poisoning. This gave the researchers a hunch.

So, they infected laboratory mice with bacteria (Citrobacter rodentium) that cause food poisoning, while also feeding them a protein found in eggs (ovalbumin). Once the mice recovered from the infection, feeding them ovalbumin alone activated intestine immune cells, whereas these cells didn’t react in control mice that had been given ovalbumin but not the bacteria.

The egg protein was now being recognised as an antigen (a foreign invading substance) by the non-control mice’s immune system.

Normally, our immune system turns a blind eye to the bits of proteins (which can be recognised as antigens by our immune system) we digest, a process called oral tolerance. But it appears that when the immune system activates in response to an infection, it also learns to see the food present at the time as a threat as well – producing antibodies to recognise and remember these antigens.

 

When the antibodies then run into the antigen again (in this case the egg protein) they hold onto it and bind with mast cells, triggering these immune cells to release histamines and their inflammatory processes.

Histamines are known to make neurons extra sensitive – explaining the abdominal pain even when the intestinal tissue is only stretched within normal limits during food digestion. 

Mice, genetically engineered to lack mast cells, did not display the same pain response, confirming the involvement of these cells.

Aguilera-Lizarraga and colleagues then tested 12 IBS patients and 8 healthy people to see if their intestines reacted the same way as the mice’s. Sure enough, injecting known food triggers like soy and cow’s milk into the IBS patients’ intestinal wall caused a similar localised immune response, but not in the healthy volunteers.

In both mice and humans the immune response was restricted to the intestines – specifically to the mouse colon where the bacterial infection had taken place – clearly distinguishing this food intolerance from food allergies, such as gluten allergies, which cause body-wide immune system activation.

“The idea that you can have a specific allergic response going on in the gut [is] a really new concept,” University of Nottingham gastroenterologist, who was not involved in the study, told Science.

While this study is only small, earlier clinical trials have shown treatment with antihistamines can improve IBS symptoms, supporting the idea that mast cell activation is a key culprit. And other similar gastrointestinal conditions have also implicated bacteria in their cause.

“Mast cells release many more compounds and mediators than just histamine,” explained Boeckxstaens. “So if you can block the activation of these cells, I believe you will have a much more efficient therapy.”

The researchers are now exploring if stress-induced IBS involves the same underlying mechanisms, and more work on the use of antihistamines to treat IBS is currently underway.

Although learning why my guts are so disagreeable is incredibly fascinating, I for one am busting for treatments that might no longer have me scrambling for the toilet just because I’ve eaten foods with onion and garlic.

This study was published in Nature.

 



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Our Forests Are on Track to Hit a Crucial Climate Tipping Point by 2050, Scientists Warn

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Forests and other land ecosystems today absorb 30 percent of humanity’s CO2 pollution, but rapid global warming could transform these natural ‘sinks’ into carbon ‘sources’ within a few decades, opening another daunting front in the fight against climate change, alarmed researchers have said.

 

Climate skeptics often describe CO2 as “plant food”, suggesting that increased greenhouse gas emissions will be offset by a massive upsurge in plant growth.

But the new study shows that beyond a certain temperature threshold – which varies according to region and species – the capacity of plants to absorb CO2 declines.

Under current greenhouse gas emission trends, plants across half the globe’s terrestrial ecosystem could start to release carbon into the atmosphere faster than they sequester it by the end of the century, researchers reported this week in Science Advances.

Ecosystems that store the most CO2 – especially tropical and boreal forests – could lose more than 45 percent of their capacity as carbon sponges by mid-century, a team led by Katharyn Duffy from Northern Arizona University found.

“Anticipated higher temperatures associated with elevated CO2 could degrade land carbon uptake,” said the study, based not on modelling but data collected over a period of 25 years.

Failure to take this into account leads to a “gross overestimation” of the role Earth’s vegetation might play in reducing global warming, the researchers warned.

 

“The temperature tipping point of the terrestrial biosphere lies not at the end of the century or beyond, but within the next 20 to 30 years.”

Key to understanding how this could happen is the difference between photosynthesis and respiration, two chemical processes essential to plant life that respond differently to rising temperatures.

Drawing energy from sunlight, plants absorb carbon dioxide through their leaves and water from the soil, producing sugar to boost growth and oxygen, which is released into the air.

This is photosynthesis, which can only happen when there is daylight.

By contrast, the transfer of energy to cells through respiration – with CO2 excreted as a waste product – happens around the clock.

Tipping points

To find out if there is a temperature beyond which land-based ecosystems would start to absorb less CO2, Duffy and her team analysed records from a global observation network, called FLUXNET, spanning 1991 to 2015.

FLUXNET essentially tracks the movement of CO2 between ecosystems and the atmosphere.

They found that global photosynthesis peaks at certain temperatures, depending on the type of plant, and then declines thereafter.

 

Respirations rates, however, increase across all types of ecosystems without appearing to reach a maximum threshold.

“At higher temperatures, respiration rates continue to rise in contrast to sharply declining rates of photosynthesis,” the study found.

If carbon pollution continue unabated, this divergence will could see the CO2 absorption drop by half as early as 2040.

“We are rapidly entering temperature regimes where biosphere productivity will precipitously decline, calling into question the future viability of the land sink,” the researchers concluded.

The findings also call into question the integrity of many national commitments under the Paris Agreement – known as nationally determined contributions, or NDCs – to reduce greenhouse gases.

“These rely heavily on land uptake of carbon to meet pledges,” the authors point out.

The study notes that capping global warming under two degrees Celsius above pre-industrial levels, the cornerstone target of the 2015 Paris climate treaty, “allows for near-current levels of biosphere productivity, preserving the majority of land carbon uptakes.”

Earth has warmed at least 1.1C so far, and is currently on track to heat up another two to three degrees by century’s end unless emissions are rapidly and drastically reduced.

In 2019, a football pitch of primary, old-growth trees was destroyed in the tropics every six seconds – about 38,000 square kilometres (14,500 square miles) in all, according to satellite data.

© Agence France-Presse

 



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Extremely Rare Phenomenon Sees Babies Inhale Cancer Cells During Vaginal Birth

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It’s not impossible for an infant to get cancer from their mother, but it doesn’t happen very often.

Researchers estimate transmission of maternal cancer to offspring occurs perhaps only twice in every million births for mothers with cancer, with the diseased cells being delivered to the infant via the placenta in these exceedingly rare and unfortunate cases.

 

But that’s not the only way a mother with cancer might unknowingly infect her child, scientists say.

In a new case study published by researchers in Japan, doctors report what appears to be a medical first: vaginal transmission of cancer cells from mothers with cervical cancer to infants at the moment of their birth.

“Mother-to-infant transmission of tumour in the birth canal during vaginal delivery is also theoretically possible,” the researchers, led by paediatric oncologist Ayumu Arakawa from the National Cancer Centre Hospital in Tokyo, explain in their paper.

“If the mother has cervical cancer, the infant can be exposed to tumour cells in fluids in the birth canal and could aspirate tumour cells into the lungs.”

This obscure and previously unknown vector – inhaling cancer in your very first breaths, ostensibly – appears to be responsible for two otherwise unlinked cases of paediatric lung cancer diagnosed in a pair of young male patients: a 23-month-old and a six-year-old.

In both cases, the patients presented to hospital with symptoms of their illness, the 23-month-old experiencing coughing, and the six-year-old experiencing chest pain.

 

In each instance, CT scans revealed what eventually turned out to be cancerous tumours in the boys’ lungs, which were successfully treated in both cases – although not easily.

Both the young patients received repeated bouts of chemotherapy, but were only cleared of disease after having operations to remove the cancerous tissue: in the case of the 23-month-old, a cancerous lobe of lung tissue was taken out, while the six-year-old needed his entire left lung removed.

While it’s impossible to know for sure how these boys developed the cancerous growths in their lungs, the researchers say they’ve identified the most probable cause.

In the case of the 23-month-old, his 35-year-old mother, who had not received a vaccination against human papillomavirus (HPV), received a diagnosis of cervical cancer just three months after the infant’s birth, having tested negative seven months before. Eventually, the tumours spread to her lung, liver, and bones, and she died.

However, analysis of the tissue from her cervical tumour and her son’s lung tumour revealed gene profile similarities in the form of certain mutations and alleles, and the lack of the Y chromosome – suggesting the boy’s cancer had come directly from his mother.

 

The six-year-old’s tumours bore the same genetic signatures of his own mother’s cervical cancer – which was first observed via a tumour that was detected during her pregnancy, but considered, unfortunately incorrectly, to be stable. She later had her uterus removed, along with her fallopian tubes and ovaries, but passed away two years after the surgery from the disease.

Based on all the above – and that both sons’ tumours also bore the hallmarks of the HPV genome – the researchers concluded the lung cancer in the children was caused by transmission of cervical tumours from the children’s mothers.

“The peribronchial [relating to airways of the respiratory system] pattern of tumour growth in both children suggested that the tumours arose from mother-to-infant vaginal transmission through aspiration of tumour-contaminated vaginal fluids during birth,” the team explains.

In most cases involving mother-to-foetus transmission of cancer, the placental delivery of cancerous cells tends to result in the spreading of cancers to the brain, bones, liver, and other tissues, including the lungs. Here, it was just the lungs – which offers a strong clue as to how the disease could have been delivered to the boys’ own bodies.

 

“In our two patients, tumours were observed only in the lungs and were localised along the bronchi,” the authors write.

“It is likely that maternal tumour cells were present in the amniotic fluid, secretions, or blood from the cervix and were aspirated by the infants during vaginal delivery.”

While the chances of this route of cancerous infection would appear to be incredibly slim for any individual family, the researchers stress that prevention via HPV vaccination would further prevent this method of transmission from occurring – an especially important message in the context of Japan, which has a troubled history with HPV vaccinations.

Further, the researchers suggest caesarean section should be the recommended form of birth for mothers with a history of uterine cervical cancer.

Beyond those takeaways, these grim cases of an extremely rare medical phenomenon serve as a remarkable example of how much we have yet to learn about cancer – and the insidious routes via which the disease appears to spread itself.

“I found it fascinating, personally,” Debbie Saslow, the senior director of HPV-related and women’s cancers at the American Cancer Society, who wasn’t involved with the study, told Health Day.

“I didn’t know this was possible.”

The findings are reported in The New England Journal of Medicine.

 





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Humanity Is Hurtling Into a ‘Ghastly Future’ It Doesn’t Comprehend, Scientists Warn

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The emergency is not invisible. But that doesn’t mean we can see it.

After decades of inaction and ineffective action on biodiversity decline, climate change, and pollution, civilisation stands on the precipice of a “ghastly future” it has gravely underestimated, an international team of scientific experts warns in an unnerving new study published this week.

 

“The scale of the threats to the biosphere and all its lifeforms – including humanity – is in fact so great that it is difficult to grasp for even well-informed experts,” the researchers, led by global ecologist Corey Bradshaw from Flinders University in Australia, explain in their paper.

“The mainstream is having difficulty grasping the magnitude of this loss, despite the steady erosion of the fabric of human civilisation.”

If the grandiose language seems almost hyperbolic, that’s only because of the incredibly high stakes of what we’re actually talking about here.

While the authors know fully well that their assessments will be denied, attacked, and ridiculed in many quarters, the knowledge doesn’t obviate them – or the scientific community they represent – of the responsibility for sharing the news.

“Our message might not be popular, and indeed is frightening,” the researchers write in a companion piece on The Conversation.

“But scientists must be candid and accurate if humanity is to understand the enormity of the challenges we face.”

According to the team’s research – a review of over 150 studies on different aspects of the worsening state of the natural world – the central problems we face are economic and political systems centred around unsustainable human consumption and population growth at the expense of all else.

 

The roots of biodiversity loss can be traced back some 11,000 years to the start of agriculture, but the problem has vastly accelerated in recent centuries due to ever-worsening pressures placed on natural ecosystems, to the extent that the reality of a sixth major extinction is now scientifically undeniable, the researchers write.

At the same time, the global human population keeps growing, having doubled since 1970, with estimates suggesting a peak population of nearly 10 billion by the end of the century.

In turn, this ever-expanding human footprint is expected to accelerate and worsen existing food insecurity, soil degradation, biodiversity decline, pollution, social inequality, and regional conflicts.

“This massive ecological overshoot is largely enabled by the increasing use of fossil fuels,” the researchers write.

“These convenient fuels have allowed us to decouple human demand from biological regeneration: 85 percent of commercial energy, 65 percent of fibres, and most plastics are now produced from fossil fuels.”

Despite all of this being considered established scientific knowledge, human life for the main part largely goes on as if it weren’t, the researchers say.

 

“Stopping biodiversity loss is nowhere close to the top of any country’s priorities, trailing far behind other concerns such as employment, healthcare, economic growth, or currency stability,” the authors write.

“Humanity is running an ecological Ponzi scheme in which society robs nature and future generations to pay for boosting incomes in the short term. Even the World Economic Forum, which is captive of dangerous greenwashing propaganda, now recognises biodiversity loss as one of the top threats to the global economy.”

Even climate change, which is a much more visible threat than biodiversity loss, appears to be too difficult for human societies to contend with, with ever-rising greenhouse gas concentrations, and continued failures by nations to effectively reduce their emissions or set effective climate targets.

Against the grim backdrop of such existential threats, electorates are increasingly embracing right-wing populist leaders with anti-environment agendas that only intensify the existing pressures, while perpetuating false paradigms that peg the ‘environment’ against the ‘economy’.

In the long term, the authors say we are looking at a “ghastly future of mass extinction, declining health, and climate-disruption upheavals (including looming massive migrations) and resource conflicts”, if we are unable to change the course of human society in a direction that prevent extinctions and restore ecosystems.

Despite the seeming fatalism of this alarming assessment, the researchers insist theirs is not a call to surrender, but rather a ‘cold shower’ humanity and its leaders seem to desperately need – a brutal reality check to snap people out of their sleepy, dangerous inertia.

“While there have been more recent calls for the scientific community in particular to be more vocal about their warnings to humanity, these have been insufficiently foreboding to match the scale of the crisis,” the scientists conclude.

“It is therefore incumbent on experts in any discipline that deals with the future of the biosphere and human well-being to eschew reticence, avoid sugar-coating the overwhelming challenges ahead and ‘tell it like it is’. Anything else is misleading at best, or negligent and potentially lethal for the human enterprise at worst.”

The findings are reported in Frontiers in Conservation Science.

 



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Calculations Show It’ll Be Impossible to Control a Super-Intelligent AI

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The idea of artificial intelligence overthrowing humankind has been talked about for many decades, and scientists have just delivered their verdict on whether we’d be able to control a high-level computer super-intelligence. The answer? Almost definitely not.

 

The catch is that controlling a super-intelligence far beyond human comprehension would require a simulation of that super-intelligence which we can analyse. But if we’re unable to comprehend it, it’s impossible to create such a simulation.

Rules such as ’cause no harm to humans’ can’t be set if we don’t understand the kind of scenarios that an AI is going to come up with, suggest the authors of the new paper. Once a computer system is working on a level above the scope of our programmers, we can no longer set limits.

“A super-intelligence poses a fundamentally different problem than those typically studied under the banner of ‘robot ethics’,” write the researchers.

“This is because a superintelligence is multi-faceted, and therefore potentially capable of mobilising a diversity of resources in order to achieve objectives that are potentially incomprehensible to humans, let alone controllable.”

Part of the team’s reasoning comes from the halting problem put forward by Alan Turing in 1936. The problem centres on knowing whether or not a computer program will reach a conclusion and answer (so it halts), or simply loop forever trying to find one.

 

As Turing proved through some smart math, while we can know that for some specific programs, it’s logically impossible to find a way that will allow us to know that for every potential program that could ever be written. That brings us back to AI, which in a super-intelligent state could feasibly hold every possible computer program in its memory at once.

Any program written to stop AI harming humans and destroying the world, for example, may reach a conclusion (and halt) or not – it’s mathematically impossible for us to be absolutely sure either way, which means it’s not containable.

“In effect, this makes the containment algorithm unusable,” says computer scientist Iyad Rahwan, from the Max-Planck Institute for Human Development in Germany.

The alternative to teaching AI some ethics and telling it not to destroy the world – something which no algorithm can be absolutely certain of doing, the researchers say – is to limit the capabilities of the super-intelligence. It could be cut off from parts of the internet or from certain networks, for example.

The new study rejects this idea too, suggesting that it would limit the reach of the artificial intelligence – the argument goes that if we’re not going to use it to solve problems beyond the scope of humans, then why create it at all?

If we are going to push ahead with artificial intelligence, we might not even know when a super-intelligence beyond our control arrives, such is its incomprehensibility. That means we need to start asking some serious questions about the directions we’re going in.

“A super-intelligent machine that controls the world sounds like science fiction,” says computer scientist Manuel Cebrian, from the Max-Planck Institute for Human Development. “But there are already machines that perform certain important tasks independently without programmers fully understanding how they learned it.”

“The question therefore arises whether this could at some point become uncontrollable and dangerous for humanity.”

The research has been published in the Journal of Artificial Intelligence Research.

 



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Every 8 Years, Swarms of Millipedes Stop Trains in Japan. Scientists Finally Know Why

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Every eight years during fall, a plague of millipedes swarm train lines in mountainous Japan, earning them the nickname ‘train millipedes’.

Working together, these small beasties (around 3 cm or 1.18 inches long) – which play a large role cycling nitrogen in Japan’s larch forests – have forced trains to come to a skidding halt.

 

Up until now, scientists weren’t quite sure what was causing them to swarm with such peculiar regularity, but a 50-year research project has finally confirmed that the species – Parafontaria laminata armigera (P. l. a.) – exists on a rare eight-year life cycle.

This confirmation is incredibly exciting, as cicadas are the only other known periodical animals with lifespans this long.

“This millipede needs seven years from egg to adult and one more year for maturation,” the team writes in their new paper.

“Thus, the eight-year periodicity of P. l. a. was confirmed by tracing the complete life history from eggs to adults in two different locations.”

We don’t know why cicadas emerge in 13- and 17-year intervals, but thanks to some incredible research, we do now understand the eight-year life cycle of the train millipedes.

cover image 002The train millipedes swarming. (Keiko Niijima)

Lead author and government ecologist Keiko Niijima first started conducting observations into these millipedes in 1972, and two main sites were surveyed between one and five times per year for many of the years between then and 2016.

It was quite an operation, and when they got to the two sites at Mt. Yatsu and Yanagisawa, the job wasn’t exactly easy and quick either.

 

“The soil to a depth of 0–5 cm was dug out, spread on a polyethylene sheet and the millipedes on the sheet were collected using forceps or an aspirator,” the researchers explain.

“Then, the same procedure was repeated for 5–10, 10–15 and 15–20 cm depths.”

Collecting any millipedes they found, they discovered that the millipedes have seven stages (called instars) of growing up, all of which stay in the soil and hibernate during winter and then molt in the summer.

“The train millipedes undertake a molting in the summer every year and have seven larval instars,” the researchers write.

“They become adults by the eighth molting after eight years from egg deposition.”

millipede train swarm image 1 (K. Niijima)

Then, the adults swarm on the surface in September and October, sometimes travelling up to 50 metres to get frisky before hibernating during the winter, and copulate again in late spring.

By August, the females have laid 400 to 1,000 eggs and the adults have all died – ready for another eight-year generation.

As with cicadas, the millipede’s eight years aren’t all in sync everywhere. 

In fact, the team suspects there are seven broods across the mountainous region of Central Japan that completed their lifecycle each in different years. That being said though, they don’t move much, so a particular train line will continue to have the same issue every eight to 16 years from one brood. 

 

Looking at historical records dating all the way back to the 1910s, the researchers were able to attribute nearly every reported millipede swarming to one of the seven broods.

“We have shown the existence of a periodical millipede, a new addition to periodical organisms with long life cycles: periodical cicadas, bamboos and some plants in the genus Strobilanthes,” the team writes.

Parafontaria laminata armigera is the first record of periodical non-insect arthropod.”

With arthropods and insects making up a huge percentage of all animals on Earth, and only a fifth having been identified or named, there’s likely to be plenty more long periodic life cycles out there.

All we’ve got to do is find them.

The research has been published in Royal Society Open Science.

 



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Most Microplastics in The Arctic Don’t Come From Trash

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Microplastics are everywhere. These tiny plastic fragments can be found throughout the oceans, infiltrating the animals within it, the food we eat, and even our children.

The proliferation extends from the highest peak in the world to the beginnings of life itself. Even the remoteness of Earth’s polar regions offers no shelter from the storm – and new research helps to explain just where this endless inundation of microplastic debris is coming from.

 

In a new study led by ocean pollution researcher Peter Ross from the Ocean Wise Conservation Association in Canada, scientists analysed the distribution of microplastics in the Arctic Ocean, sampling the contaminants in near-surface seawater at 71 sites across the European and North American Arctic, including the North Pole.

In addition to near-surface sampling – collecting microplastics at depths of 3 to 8 metres (10 to 26 ft) – the researchers also sampled at much lower depths in the Beaufort Sea to the north of Alaska and Canada, collecting microplastics at depths as low as 1,015 metres (3,330 ft) in the water column.

While it’s already known that microplastics have permeated the most remote reaches of the world, the mechanisms underlying their distribution and the scale of contamination remains unclear, the researchers say.

Here, the team used Fourier-transform infrared spectrometry to confirm an average Arctic-wide count of approximately 40 microplastic particles per cubic metre of ocean water, with the vast majority being microplastic fibres (92.3 percent), of which almost three-quarters (73.3 percent) were polyester.

But that’s not all.

“Particle abundance correlated with longitude, with almost three times more particles in the eastern Arctic compared to the west,” the researchers write in their paper, and in terms of the polyester pollutants, “an east-to-west shift in infra-red signatures [points] to a potential weathering of fibres away from source.”

 

In short, the researchers think that polyester fibres are delivered to the eastern Arctic Ocean from the Atlantic Ocean and possibly also via atmospheric transport from the south, breaking down into smaller pieces as they degrade and move to the west Arctic.

The culprit, the team suggests, is textile fibres in domestic wastewater, with polyester and synthetic fibres being shed from clothing when washed, before passing into waterways that transport the contaminants to the ocean.

According to the researchers’ estimates, a single apparel item can release millions of fibres during a typical domestic wash, and wastewater treatment plants can release over 20 billion microfibres annually.

“These estimates follow reports of large numbers of microfibres being shed by various textiles in home laundry, and a dominance of synthetic microfibres in municipal wastewater,” the authors explain.

“While further inventories will no doubt add to the source identification of Arctic MPs, we suggest that the combined, historical release of wastewater from Europe, the Americas and Asia, warrants additional scientific scrutiny.”

That’s putting it mildly. As Ross explains in a video from 2018, it’s imperative that we track where microplastic pollution is coming from, if we’re ever to have a chance of stopping this insidious threat.

“The more we look for microplastics in our environmental samples, the more we realise… we’re in a cloud of plastic dust,” Ross says. “Everywhere we look, we find microplastics… microplastics are everywhere.”

The findings are reported in Nature Communications.

 



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Scientists Engineer New ‘Living Materials’ by Hacking The Basis of Kombucha

in Science News by


Scientists have created new kinds of ‘living materials’ by tweaking the base ingredients of kombucha – the popular tea drink fermented with a symbiotic culture of bacteria and yeast (aka SCOBY).

 

This kind of ‘tea fungus’ – sometimes called ‘kombucha mother’ – can do a lot more than just produce sour-tasting beverages, it seems.

By modifying the mixture of the culture, researchers were able to make engineered living materials (ELMs) that could one day have all sorts of practical applications, such as sensing light or detecting contaminants.

Better still, the scientists say these living materials can easily be made at home, much like tending a sourdough starter in your kitchen.

010 kombucha material 2(Imperial College London/MIT)

“Although we are still far from a future in which people can cheaply grow their own biological sensors, our new system moves us forward by creating materials that are scalable and therefore more likely to be useful in the real world,” says co-first author and synthetic biologist Charlie Gilbert from Imperial College London.

The roots of the current work trace back to 2014, when researchers at MIT engineered Escherichia coli cells to generate biofilms embedded with non-living structures such as gold nanowires.

While the innovation showed what ELMs were capable of, it did so at a microscopic scale, rendering the fabricated materials virtually useless for practical purposes.

 

The challenge was to do the same thing on a much larger scale, which led researchers eventually to experimentation with kombucha – or, rather, to the symbiotic culture that serves as its mother.

“We think this is a good system that is very cheap and very easy to make in very large quantities,” says co-first author and biological engineer Tzu-Chieh Tang from MIT.

“It’s at least a thousand times more material than the E.coli system.”

010 kombucha material 2(Tzu-Chieh Tang/Christoph Bader/Rachel Smith)

To create their ELMs, the researchers experimented with a strain of laboratory yeast called Saccharomyces cerevisiae, combining it with the bacterium Komagataeibacter rhaeticus.

With lots of trial and error – involving finding the right ratio of yeast to bacteria, and experiments to perfect the density of the SCOBY mixture – the researchers eventually succeeded.

Within the engineered culture – called Syn-SCOBY – the bacteria produce large-scale amounts of cellulose, which acts as a scaffold structure, within which S. cerevisiae and its enzymes can perform various (programmed) functions, such as sensing chemicals in pollutants or pathogens, or making a protein that glows in the presence of blue light.

 

It’s early days, but this kind of system points to the future possibility of advanced, so-called ‘smart’ materials being locally made in the comfort of people’s homes, rather than requiring resource-intensive manufacturing in a factory far away.

“Pretty much everyone can do this in their kitchen or at home,” Tang says. “You don’t have to be an expert. You just need sugar, you need tea to provide the nutrients, and you need a piece of Syn-SCOBY mother.”

The findings are reported in Nature Materials.

 



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