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oxygen

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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In a First, Scientists Say They’ve Partially Reversed a Cellular Aging Process in Humans

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Every time a cell inside your body replicates, a slither of your youth crumbles to dust. This occurs via the shortening of telomeres, structures that ‘cap’ the tips of our chromosomes.

 

Now, scientists in Israel say they’ve been able to reverse this process and extend the length of telomeres in a small study involving 26 patients.

The participants sat in a hyperbaric oxygen chamber for five 90 minutes sessions per week over three months, and as a result, some of their cell’s telomeres were extended by up to 20 percent.

It’s an impressive claim – and something many other researchers have attempted in the past without success. But of course it’s worth flagging that this is a small sample size, and the results will need to be replicated before we can get too excited. 

However, the fact that hyperbaric oxygen therapy appears to affect telomere length is a compelling link worth investigating further. 

Lead researcher Shair Efrati, a physician from the Faculty of Medicine and Sagol School of Neuroscience at Tel Aviv University, explained to ScienceAlert how the inspiration behind their experiment was somewhat out of this world.

“After the twin experiment done by NASA, where one of the twins was sent out to the outer space and the other stayed on Earth, demonstrated a significant difference in their telomere length we have realised that changes in the outside environment may affect the core cellular changes that happens along ageing,” said Efrati.

 

Telomeres are repeating chunks of code that act as the DNA equivalent of the plastic or metal aglet capping the end of a shoelace.

They copy themselves along with the rest of the chromosomes whenever a cell divides. Yet with every replication, tiny fragments of code from the very tip of the sequence fail to make it into the new copy, leaving the freshly minted chromosome a touch shorter than its predecessor.

As anybody who has lost the cap of their shoelace knows, it doesn’t take long for the shoelace to lose its integrity. Similarly, shorter telomeres put sequences further down the chromosome at higher risk of hazardous mutations.

These mutations coincide with changes that predispose us to a bunch of age-related conditions, not least of all diseases such as cancer.

That’s not necessarily to say that we age because our telomeres shrink, but there is a connection between telomere length and health that researchers are keen to investigate further.

“Longer telomeres correlates with better cellular performance,” Efriti explained.

There are plenty of ways to accelerate the erosion of our telomeres. Failing to get adequate sleep could do it, as might chowing down on too much processed food, and maybe even having kids.

 

Slowing down the loss takes a bit more effort, but engaging in regular exercise and eating well are sound bets if you want your chromosomes to remain as long as possible.

A real achievement would be to flip our chromosomal hourglass completely and return lost sections of telomere. The fact that high-turnover tissues lining our gut do this naturally using an enzyme called telomerase has fuelled research over the years.

There have been plenty of milestones in attempts to achieve this task. Gene therapy in mice has shown it could one day be feasible in humans. More recently, stem cells from a supercentenarian woman had their telomeres completely reset outside of her body.

Some studies have found potential for tiny increases of maybe a few percent with provision of nutritional supplements such as vitamin D.

But while there are plenty of hyped promises of reversing aging in living humans already on the market, the reality of science-backed therapies we can use to give us the telomeres of a 20-year-old has been underwhelming.

Which is why the latest study is attracting so much attention. Far from a measly two or three percent, this latest study found telomeres in white blood cells taken from 26 subjects had regained around a fifth of their lost length.

 

The key, it seems, is hyperbaric oxygen therapy (HBOT) – the absorbing of pure oxygen while sitting in a pressurised chamber for extensive periods; in this case, five 90 minute sessions per week over three months.

HBOT has attracted controversy in the past for claims it could treat a range of conditions. It’s usually the kind of therapy you’d give a diver who came up too fast from the ocean depths, or to kill off oxygen-sensitive microbes in a wound that just won’t heal any other way.

But oxygen-rich environments are also behind a weird paradox, one where the body desperately stirs up a host of genetic and molecular changes that typically occur in a low oxygen one.

In this study, the researchers were able to show that the genetic changes provoked by the HBOT has extended telomeres, and also had a potentially positive effect on the health of the tissues themselves.

A slightly smaller sample of volunteers also showed a significant decrease in the number of senescent T cells, tissues that form a vital part of our immune system’s targeted response against invaders.

Whether you’d sit in a small tank every day for a quarter of a year is a matter of preference, but future research could help make the whole process a touch more efficient, at least for some.  

“Once we have demonstrated the reverse ageing effect on the study cohort using predefined HBOT protocol, further studies are needed in order to optimise the specific protocol per individual,” Efrati told ScienceAlert.

In a press release from The Sagol Center for Hyperbaric Medicine and Research, Efrati says understanding telomere shortening is “considered the ‘Holy Grail’ of the biology of aging”.

As significant as telomere shrinking seems to be, the failure of our biology as we age is no doubt a complicated matter involving far more than lost pieces of chromosomes.

Reactivation of telomerase is also a trick used by cancers to remain ahead of the growth-curve, making this holy grail a potentially poisoned chalice we need to understand better before drinking too heavily from.

Excitingly, research like this will help us develop a better picture of the aging process.

This research was published in Aging.

 



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Here’s How The Steroid Dexamethasone Can Make a COVID-19 Patient Feel

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President Trump started a course of the steroid dexamethasone on Saturday after a drop in blood oxygen levels, his doctor Sean Conley said. The drug treats the symptoms of COVID-19 by targeting the immune system, resulting in relief from fever and a boost in energy.

 

The corticosteroid is typically reserved for the sickest patients, according to the World Health Organisation. Despite the presumed severity of the president’s condition, he continues to project an image of good health.

“I feel better than I did 20 years ago!” Trump tweeted on Monday, announcing his discharge from Walter Reed National Military Medical Centre. That may have been the steroid talking.

It’s possible that dexamethasone could give Trump a false sense of recovery, said Panagis Galiatsatos, MD, a pulmonary physician at Johns Hopkins Bayview Medical Centre.

“Everyone who gets steroids feels a little bit better,” Galiatsatos told Business Insider.

“You get a steroid euphoria in addition to no fevers and so forth. So yes, there will be a moment in time where he’s going to feel like, ‘Oh, this is all behind me now.'”

Along with acute euphoria, side effects of dexamethasone can include high blood sugar, sleep impairment, and psychosis, Galiatsatos said. COVID-19 patients typically receive 6mg of the steroid once per day for 10 days, as recommended based on the results of a clinical trial in the UK.

 

‘It can make you feel good even though the disease is still pretty bad’

Even if Trump is feeling better since receiving the steroid, he still has a more than one in five chance of dying of COVID-19 given that he required supplemental oxygen, Bob Wachter, chair of the Department of Medicine at the University of California San Francisco, told Business Insider.

That probability increases given his additional risk factors, such as age and weight, and he has an even higher chance of needing intensive care if his respiratory symptoms worsen down the line.

“He’s on a medicine, dexamethasone, that can kind of cover up some of the symptoms,” Wachter said.

“It can make you feel good even though the disease is still pretty bad in you. It doesn’t really change the risk that much.”

Dexamethasone reduced the mortality rate for COVID-19 patients who were sick enough to require supplemental oxygen, the British RECOVERY trial found.

The reduction in mortality was greater for patients who required invasive mechanical ventilation than for patients who received non-invasive oxygen, such as the president. The latter group saw the mortality rate drop from 26.2 to 23.3 percent.

 

Steroids weaken the immune response, so it may take longer to clear the virus

The benefits of taking a steroid like dexamethasone come with the cost of potentially extending the course of illness. Steroids target the immune system, not the virus itself, and a weaker immune system will take longer to fight off the virus.

Galiatsatos said doctors prescribe steroids when the immune system is overly aggressive, such as in the case of “cytokine storms” that cause some coronavirus cases to turn deadly.

Both dexamethasone and remdesivir, another medication that Trump is taking according to his doctors, are meant to curtail the hyperactive immune response, while still allowing the immune system to continue doing what it’s supposed to do: fighting off the virus.

“It’s like putting up a fence around a bulldog. The bulldog will be there to do its stop and protect, but the fence – a.k.a. the steroid – is meant to not unleash the dog on everyone else,” Galiatsatos said.

If prescribed to healthy patients or those with mild symptoms, dexamethasone can destroy a well-functioning immune system, Galiatsatos said. Trump’s getting prescribed the steroid would suggest that he’s sicker than his doctors are letting on.

The National Institutes of Health recommended against giving dexamethasone to patients who don’t need assistance breathing, stipulating that the steroid is recommended only for patients who need a ventilator or extra oxygen.

 

Coronavirus symptoms can get better before they get worse

Even without a steroid putting a leash on the immune system, doctors have observed coronavirus patients getting better, and then worse.

Michelle Gong, the director of critical-care research at Montefiore Medical Centre, said in a Q&A with the Journal of the American Medical Association in March that COVID-19 patients often seem to be “doing OK, and then at around the five- to seven-day mark they start to get worse and then develop respiratory failure.”

According to the Centres for Disease Control and Prevention, the median time from onset of symptoms to acute respiratory distress syndrome was eight to 12 days, and the median time from onset of symptoms to ICU admission was 10 to 12 days.

Trump’s top doctor told reporters on Monday that the president “may not entirely be out of the woods” for another week or so, despite an altogether optimistic evaluation of POTUS’ condition.

“This isn’t meant to cure. It’s just meant to kind of keep things at bay,” Galiatsatos said of the dexamethasone.

“Even after the 10 days of getting the treatment, he will still be fighting the infection, and it could still do horrible things.”

This article was originally published by Business Insider.

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We May Finally Know What Life on Earth Breathed Before There Was Oxygen

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Billions of years ago, long before oxygen was readily available, the notorious poison arsenic could have been the compound that breathed new life into our planet.

In Chile’s Atacama Desert, in a place called Laguna La Brava, scientists have been studying a purple ribbon of photosynthetic microbes living in a hypersaline lake that’s permanently free of oxygen.

 

“I have been working with microbial mats for about 35 years or so,” says geoscientist Pieter Visscher from the University of Connecticut.

“This is the only system on Earth where I could find a microbial mat that worked absolutely in the absence of oxygen.”

Microbial mats, which fossilise into stromatolites, have been abundant on Earth for at least 3.5 billion years, and yet for the first billion years of their existence, there was no oxygen for photosynthesis.

How these life forms survived in such extreme conditions is still unknown, but examining stromatolites and extremophiles living today, researchers have figured out a handful of possibilities. 

While iron, sulphur, and hydrogen have long been proposed as possible replacements for oxygen, it wasn’t until the discovery of ‘arsenotrophy‘ in California’s hypersaline Searles Lake and Mono Lake that arsenic also became a contender.

Since then, stromatolites from the Tumbiana Formation in Western Australia have revealed that trapping light and arsenic was once a valid mode of photosynthesis in the Precambrian. The same couldn’t be said of iron or sulphur.

Just last year, researchers discovered an abundant life form in the Pacific Ocean that also breathes arsenic. 

 

Even the La Brava life forms closely resemble a purple sulphur bacterium called Ectothiorhodospira sp., which was recently found in an arsenic-rich lake in Nevada and which appears to photosynthesise by oxidising the compound arsenite into a different form -arsenate.

While more research needs to verify whether the La Brava microbes also metabolise arsenite, initial research found the rushing water surrounding these mats is heavily laden with hydrogen sulphide and arsenic.

If the authors are right and the La Brava microbes are indeed ‘breathing’ arsenic, these life forms would be the first to do so in a permanently and completely oxygen-free microbial mat, similar to what we would expect in Precambrian environments.

As such, its mats are a great model for understanding some of the possible earliest life forms on our planet. 

While genomic research suggests the La Brava mats have the tools to metabolise arsenic and sulphur, the authors say its arsenate reduction appears to be more effective than its sulfate reduction.

Regardless, they say there’s strong evidence that both pathways exist, and these would have been enough to support extensive microbial mats in the early days of life on Earth.

If the team is right, then we might need to expand our search for life forms elsewhere.

“In looking for evidence of life on Mars, [scientists] will be looking at iron and probably they should be looking at arsenic also,” says Visscher.

It really is so much more than just a poison.

The study was published in Communications Earth and Environment

 



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Bizarre Discovery Reveals The Moon Is Rusting, Even Without Liquid Water And Oxygen

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The Moon, our closest cosmic neighbour, and the only other body in the Solar System on which humans have set foot, is fairly well known to us. We know that there is practically no air. We know that there is water ice, but no liquid water.

 

So you can understand why the detection of haematite on the Moon has scientists baffled, since haematite is an oxidised form of iron that, here on Earth, requires the presence of both air and water to form.

Especially since the Moon is constantly bombarded with a stream of hydrogen from the solar wind, a reducing agent that ‘donates’ its electrons to the materials it interacts with. Oxidisation occurs due to a loss of electrons – so even if all of the right elements were present for oxidisation to occur, the solar wind should cancel it out.

“It’s very puzzling,” said planetary scientist Shuai Li of the University of Hawaii at Manoa. “The Moon is a terrible environment for haematite to form in.”

010 moon rustingEnhanced map of the haematite at the lunar north pole. (Shuai Li)

The haematite in question was discovered in data collected by the Indian Space Research Organisation’s Chandrayaan-1 orbiter. The Moon Mineralogy Mapper (M3) designed by NASA’s Jet Propulsion Laboratory uses hyperspectral imaging to perform a granular spectroscopic analysis, giving a detailed breakdown of the Moon’s surface mineral composition.

In this way, Li and his colleagues identified ice deposits at high latitudes around the lunar poles in 2018. But, when he was examining the data, Li noticed something strange.

 

“When I examined the M3 data at the polar regions, I found some spectral features and patterns are different from those we see at the lower latitudes or the Apollo samples,” Li said.

“I was curious whether it is possible that there are water-rock reactions on the Moon. After months of investigation, I figured out I was seeing the signature of haematite.”

Which raised a big question: how the heck did it get there? Well, a big hint could lie in how the haematite is distributed. It corresponds pretty strongly with traces of water previously identified and linked to impacts. Scientists believe that water ice could be mixed in with the lunar regolith, and excavated and melted during impact events.

The haematite is also mostly found on the side of the Moon that is always facing Earth. That, according to the researchers, is really interesting.

“More hematite on the lunar nearside suggested that it may be related to Earth,” Li said.

“This reminded me of a discovery by the Japanese Kaguya mission that oxygen from Earth’s upper atmosphere can be blown to the lunar surface by solar wind when the Moon is in Earth’s magnetotail. So, Earth’s atmospheric oxygen could be the major oxidant to produce haematite.”

 

During the full Moon, our satellite is in Earth’s magnetotail, the trailing region of the magnetosphere away from the Sun. At these times, over 99 percent of the solar wind is blocked from reaching the Moon, which means that pesky hydrogen reducing agent isn’t getting all up in the oxidation process.

Combine these three ingredients – minute amounts of molecular water, minute amounts of oxygen, and a brief window of time each month in which rust can form freely – and, over a few billion years, you can get haematite on the Moon.

That doesn’t mean the mystery is completely solved, however.

“Interestingly, haematite is not absolutely absent from the far-side of the Moon where Earth’s oxygen may have never reached, although much fewer exposures were seen,” Li said.

“The tiny amount of water observed at lunar high latitudes may have been substantially involved in the haematite formation process on the lunar far-side, which has important implications for interpreting the observed haematite on some water poor S-type asteroids.”

Getting our hands on the mineral itself would be really interesting. It’s possible that haematite deposits over a range of ages could still retain oxygen isotopes from different ages in Earth’s history, dating back billions of years. This could be really useful for understanding our planet’s atmospheric evolution.

And, of course, it would be deeply enlightening for understanding the Moon’s history, too.

“This discovery will reshape our knowledge about the Moon’s polar regions,” Li said. “Earth may have played an important role on the evolution of the Moon’s surface.”

The research has been published in Science Advances.

 



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Here Are 6 Myths About Masks That People Really Need to Stop Sharing

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In recent months, masks have become a highly polarising topic. Despite intense debates online, and the sometimes violent conflicts that erupt in public about mask requirements, the science behind mask-wearing is not at all controversial.

 

There’s extensive evidence to support wearing a mask to protect both yourself and other people, and help slow the spread of the coronavirus.

Here are some of the most common myths used to argue against mask-wearing, and why they’re wrong.

Wearing a mask won’t worsen a coronavirus infection

Myth: If I have the virus, wearing a mask means I’ll be re-exposed to viral particles I exhale, making me sicker.

Fact: This claim was circulated in the pseudoscience documentary Plandemic, which has been thoroughly debunked by scientists.

You can’t reinfect yourself if you already have the virus, and it’s impossible for it to somehow “reactivate” in your body, research has shown.

“There is no science behind it, and it’s totally false,” microbiologist Dr. Miryam Wahrman, author of The Hand Book: Surviving in a Germ-filled World, previously told Business Insider about this claim.

More and more evidence suggests that once your body mounts an immune response to COVID-19, it’s protected – for some time – from reinfection.

Masks don’t reduce your oxygen levels

Myth: I can’t breathe in a mask. It might be dangerous to wear one because it could limit my oxygen levels.

Fact: Masks have consistently been shown to be safe, which is why they were already used heavily by medical personnel even before the pandemic. The common rumour that they reduce the oxygen saturation level of your blood has been debunked by multiple medical doctors.

Furthermore, despite claims that a mask could exacerbate health conditions like asthma, doctors have repeatedly stated that there’s no legitimate reason for a medical exemption from wearing a mask. Strategies like fitting your mask properly and choosing the right type of mask can help.

You can even work out in a mask until it becomes saturated with sweat, at which point it’s less effective.

Certain types of industrial-quality sealed respirators may affect levels of oxygen intake, especially when worn for a prolonged period of time, but the most common types of protective mask, such as surgical masks and cloth masks, will not interfere with oxygen levels.

You should wear a mask even if you don’t have symptoms

Myth: If I feel fine and don’t have a cough or fever, I don’t need to wear a mask.

Fact: As many as 40 percent of people infected with the coronavirus show no symptoms at all. These asymptomatic carriers of the virus can still spread it to other people without ever knowing they were sick in the first place.

Even people who do show signs of illness can be contagious before symptoms appear, research has shown.

This could be particularly crucial for young people as schools struggle to reopen this fall, since there is some evidence children are more likely to spread the virus without symptoms than adults.

That makes it especially important to have a consistent and comprehensive policies on mask-wearing to help slow the spread of the virus as people return to public life.

Masks protect the people around you

Myth: Only people who are afraid of getting sick should wear masks. If I’m healthy or brave, I don’t have to.

Fact: The primary benefit of wearing a mask is to prevent the people around you from getting sick, which is why it’s so important for everyone to do it, according to research.

Masks work by blocking potentially-contagious respiratory particles from flying out into the surrounding air (and onto other people) every time you cough, sneeze, breathe, or speak. They can also prevent you from breathing in some particles expelled by other people.

Inconsistent messaging about masks from health officials early on in the pandemic may have contributed to this myth, leading some people to believe healthy people don’t need masks.

 

But based on the latest research, the most effective scenario for reducing coronavirus infection is when everyone involved wears a mask.

In a recent study from the CDC, masks helped to stop an outbreak at a hair salon in Missouri. Even though two employees were asymptomatic carriers of the virus, not a single one of 139 clients got sick, since clients and stylists all wore masks.

Neck gaiters don’t increase your risk of viral infection

Myth: Research found that neck gaiters, the fleece wraps that runners often use, are worse for coronavirus risk than no mask at all.

Fact: study from Duke University researchers swept the internet this month, reportedly finding that people who wear neck gaiters would be safer wearing no mask at all.

But these results were framed out of context. The study was not looking at the effectiveness of masks. In fact, researchers were studying how to measure a mask’s effectiveness.

This is a key distinction since, as the researchers themselves note, the results were not intended to be comprehensive, but just to demonstrate that the methodology could work for larger-scale studies on masks to help compare their effectiveness.

It’s true that some masks may be more effective than others, but more research is needed to understand how neck gaiters measure up in terms of effectiveness.

The science is clear that wearing a mask can help reduce the spread of the virus

Myth: Wearing a mask is an issue of politics, freedom, or just “virtue-signalling”, and doesn’t make a practical difference in whether or not people get sick.

Fact: The research is unambiguous. Masks work to reduce the spread of infectious viral particles, thereby preventing additional cases of the virus. Recent research from the UK found the getting the entire population to wear masks could be enough to slow the virus without resorting to lockdowns.

The more people wear masks, the more effectively a community can control the disease.

Health officials in the US, which has struggled to contain the coronavirus, are urging the public to wear masks after models have suggested doing so could save thousands of lives.

Masks don’t replace other precautions like social distancing and hand-washing

Myth: If I wear a mask, I can be close to other people or in large groups without worrying.

Fact: While the research is clear that masks work, masks alone aren’t enough. Health experts continue to recommend other precautions to slow the spread of the virus, such as washing your hands frequently and maintaining at least a 6-foot (2-metre) distance from others whenever possible.

Research has shown that these preventative measures, when combined, can significantly reduce the rate of transmission and save lives.

This article was originally published by Business Insider.

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Microbes Living Deep Below Earth’s Surface Could Be Remnants of Ancient Life Forms

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There’s an enormous variety of life thriving deep beneath Earth’s surface. A new analysis of two major groups of subsurface microbes has now revealed that their evolutionary path to life in the dark has been more curious than we expected.

 

In our planet’s first 2 billion years of existence, there was no oxygen in the atmosphere. Once the air on our blue planet changed, not all life forms adapted, with many microbes retreating into less oxygenated parts of the planet.

Patescibacteria and DPANN are two ubiquitous groups of such subsurface microbes – bacteria and archaea, respectively – that appear to have very simple genomes. This has led many to suspect that without the ability to breathe oxygen, these microbes might need to rely on complex interactions with other organisms to supplement their simple lifestyles. 

Now, it seems we may not be giving them enough credit. New research indicates that instead of having a symbiotic dependency on other major groups of organisms, most Patescibacteria and DPANN live as completely free cells. 

“These microbes [..] are really special, really exciting examples of the early evolution of life,” says Ramunas Stepanauskas, who studies microbial biology and evolution at the Bigelow Laboratory for Ocean Sciences.

“They may be remnants of ancient forms of life that had been hiding and thriving in the Earth’s subsurface for billions of years.”

 

Previous work on Patescibacteria and DPANN has gathered a small number of examples near the surface of the Earth, and mainly in North America, but this new study goes deeper and wider than ever before, analysing nearly 5,000 individual microbial cells from 46 locations around the globe, including a mud volcano on the bottom of the Mediterranean Sea, hydrothermal vents in the Pacific, and gold mines in South Africa.

“Our single cell genomic and biophysical observations do not support the prevailing view that Patescibacteria and DPANN are dominated by symbionts,” the authors write.

“Their divergent coding potential, small genomes, and small cell sizes may be a result of an ancestral, primitive energy metabolism that relies solely on [fermentation].” 

Fermentation is one of the metabolic options living organisms have for breaking down glucose without the help of oxygen, and many life forms use fermentation for energy production, especially the microbes that don’t breathe air at all. 

However, using fermentation is less efficient than breathing – it produces only 2 ATP per glucose compared to 38 ATP per glucose with aerobic respiration – so this type of metabolism comes with the cost of putting organisms in the metabolic slow lane. 

 

Patescibacteria and DPANN are just fine with that, however. Based on the new analysis, the two groups contain no trace of what’s known as an electron transport chain, a metabolic process that makes energy by dumping electrons onto oxygen. Their relatively simple, potentially ancient survival tricks simply don’t need it.

Genomic research and direct experimental tests on samples representing the two groups showed no evidence of respiration, and close examination of cell-to-cell links revealed most were on their own, not attached to hosts like some of their surface cousins.

The authors can’t deny that some symbiotic relationships could have been shaken apart by human handling, but gentle mixing was attempted when sorting the cells. 

Even if the team is underestimating cell-to-cell interactions, genomic analysis found no evidence of evolutionary enrichment from symbiotic relationships compared to other phyla.

Rather, genome content and lab analysis of cell physiology suggests these microbial groups contain few, if any, other ways of producing energy than fermentation.

“Our findings indicate that Patescibacteria and DPANN are ancient forms of life that may have never learned how to breathe,” says Stepanauskas.

“These two major branches of the evolutionary tree of life constitute a large portion of the total microbial diversity on the planet – and yet they lack some capabilities that are typically expected in every form of life.”

The study was published in Frontiers in Microbiology.

 



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Magical Photo From The ISS Captures Two Enchanting Earth Phenomena in One Image

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Earth is a genuinely magical place.

We know that’s not the sort of thing you’d expect to read on a science website, but just take a look at the photo above – a pre-dawn picture taken by an Expedition 62 crew member on the International Space Station (ISS) back in March.

 

In this image, taken when the ISS was flying just south of the Alaskan Peninsula, the fantastic colours you’re seeing are particles in Earth’s upper atmosphere interacting in different ways, resulting in two entirely different atmospheric phenomena in one picture.

Truly magical to look at, but also easily explained with some science.

The first phenomenon is the aurora – the glowing green, red-tipped phenomenon on the left side of the image. Auroras occur when charged particles from the solar wind hit Earth’s magnetosphere – a kind of protective cloak where such particles are at the whims of our magnetic field.

Mixed with atmospheric gases such as oxygen and nitrogen, the particles create the colours we know as the aurora.

Excited by solar wind, oxygen atoms at the highest altitude release this excess energy as the red glow, while and green is caused by excited oxygen or nitrogen molecules releasing energy at lower altitudes.

But the aurora is only one part of this particular shot. Moving right on the image above, take a look at the yellow-red band of light right above the curve of our planet. It’s called an ‘airglow’, and it’s more subtle than the aurora, but just as cool.

 

To understand airglow – more specifically nightglow – you need to remember that the night sky is never completely dark, not even once you’ve extracted light pollution, starlight, and diffuse sunlight.

Instead, atoms produce ’emissions’ from being in their excited state. For example, oxygen that’s been broken apart during the day recombine and release their extra energy as photons at night. Nitrogen molecules and reactions between nitrogen and oxygen contribute to this glow as well.

nightglow replacement AugustEarth’s nightglow. (NASA)

The photons released in this case appear green, as in this image above, but yellow sometimes occurs at a lower layer (around 80 to 100 kilometres above the surface of Earth).

Meteors break up in this layer of the atmosphere, and release sodium atoms into the air, hence it’s aptly named the sodium layer; excited sodium atoms will create a distinctly yellow glow.

As a bonus, the rising sun behind Earth is causing the edge of the planet to appear dark blue. This occurs for the same reason that the sky is blue during the day – when sunlight hits the molecules in our atmosphere, blue light (one of the shortest wavelengths) is scattered, while other coloured light is mostly let through.

We told you, absolutely magical.

 



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NASA’s Rover Is Taking a Tree-Like Device That Converts CO2 Into Oxygen to Mars

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NASA’s Perseverance Mars rover launched from Cape Canaveral, Florida, on 30 July, carrying a host of cutting-edge technology including high-definition video equipment and the first interplanetary helicopter.

 

Many of the tools are designed as experimental steps toward human exploration of the red planet. Crucially, Perseverance is equipped with a device called the Mars Oxygen In-Situ Resource Utilization Experiment, or MOXIE: an attempt to produce oxygen on a planet where it makes up less than 0.2 percent of the atmosphere.

Oxygen is a cumbersome payload on space missions. It takes up a lot of room, and it’s very unlikely that astronauts could bring enough of it to Mars for humans to breathe there, let alone to fuel spaceships for the long journey home.

That’s the problem MOXIE is looking to solve. The car-battery-sized robot is a roughly 1 percent scale model of the device scientists hope to one day send to Mars, perhaps in the 2030s.

Like a tree, MOXIE works by taking in carbon dioxide, though it’s designed specifically for the thin Martian atmosphere. It then electrochemically splits the molecules into oxygen and carbon monoxide, and combines the oxygen molecules into O2.

It analyses the O2 for purity, shooting for about 99.6 percent O2. Then it releases both the breathable oxygen and the carbon monoxide back into the planet’s atmosphere. Future scaled-up devices, however, would store the oxygen produced in tanks for eventual use by humans and rockets.

54ad8d226bb3f7a01aba7179A breakdown of the components inside the MOXIE oxygen generator. (NASA/Wikimedia Commons)

The toxicity of the carbon monoxide produced isn’t a worry, according to Michael Hecht, a principal investigator for MOXIE. The gas reenters the Martian atmosphere but won’t alter it very much.

“If you release the carbon monoxide into the Mars atmosphere, eventually it will combine with a very small amount of residual oxygen that’s there and turn back into carbon dioxide,” Hecht previously told Business Insider.

 

For that reason, the carbon monoxide also wouldn’t hinder a potential biosphere on Mars – a closed, engineered environment where Earthly life could thrive.

Because MOXIE is a small proof-of-concept experiment, it won’t produce much oxygen – if all goes well, it should be producing about 10 grams per hour, which is roughly the amount of oxygen in 1.2 cubic feet of Earth air. For context, humans need about 19 cubic feet of air per day.

MOXIE will test its capabilities by producing oxygen in one-hour increments intermittently throughout the duration of Perseverance’s mission, according to NASA. The device should start working soon after the rover lands on 18 February 2021.

This article was originally published by Business Insider.

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Scientists Have ‘Woken Up’ Microbes Trapped Under The Seafloor For 100 Million Years

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Researchers have successfully revived tiny microbes trapped dormant in a seemingly lifeless zone of the seabed for more than 100 million years.

A team of scientists from Japan and America were looking to see whether microscopic life survives in the less-than-hospitable conditions beneath the seafloor of the Pacific Ocean.

 

“We wanted to know how long the microbes could sustain their life in a near-absence of food,” said microbiologist Yuki Morono from the Japan Agency for Marine-Earth Science and Technology, who led the study.

They got their answer: microbes that had been trapped in seabed sediments deposited 100 million years ago could be revived with the right food and a bit of added oxygen.

Which is impressive. The pressure is immense for microbes on the seafloor, all that water stacked on top of the seabed. Not to mention the lack of oxygen, few essential nutrients, and the measly energy supplies.

When life gets trapped in other high-pressure environments, fossils usually form given a million years or more, but these mighty microbes were very much alive. 

“We knew that there was life in deep sediment near the continents where there’s a lot of buried organic matter,” said Morono’s colleague, geomicrobiologist Steven D’Hondt from University of Rhode Island. “But what we found was that life extends in the deep ocean from the seafloor all the way to the underlying rocky basement.”

The soil the microbes were trapped in was taken from a 2010 expedition to the South Pacific Gyre, a seemingly lifeless zone in the centre of swirling ocean currents to the east of Australia, known as one of the most food-limited and life-deficient parts of the ocean (and a trash vortex, with all the plastic pollution it gathers at the surface).

As part of a 2010 expedition onboard the JOIDES Resolution drillship, the team extracted sediment cores going as deep as 75 meters (250 feet) below the seafloor, which rests nearly 6 kilometres (almost 20,000 feet) below the ocean’s surface.

 

They took samples from ancient pelagic clay, which accumulates in the deepest and most remote parts of the ocean, and much younger and chalky nannofossil oozes, between 4.3 and 13 million years old.

They found oxygen-consuming microbes (and dissolved oxygen) right through every layer of the cores, from top to bottom, and at every site they sampled in the South Pacific Gyre. But the microbes were hiding out in very low numbers.

On board the ship, samples were taken out of the sediment cores to see if the energy-starved microbes had retained their “metabolic potential” and could feast and multiply.

The ancient microbes were given a boost of oxygen and fed traceable substrates containing carbon and nitrogen, their food of choice, before the glass vials were sealed, incubated and only opened after 21 days, 6 weeks or 18 months.

Even in the oldest sediments sampled, the researchers were able to revive up to 99 percent of the original microbial community.

“At first I was sceptical, but we found that up to 99.1 percent of the microbes in sediment deposited 101.5 million years ago were still alive and were ready to eat,” Morono said.

 

After their lengthy incubation, the microbial communities were sorted based on their genes. The researchers reported the seafloor soils were dominated by bacteria, but not the type that form spores, which means they were ready to grow as soon as they were given the right food.

Some microbes had quadrupled in numbers and consumed the available carbon and nitrogen 68 days into their incubation.

“It shows that there are no limits to life in the old sediment of the world’s ocean,” D’Hondt said. “In the oldest sediment we’ve drilled, with the least amount of food, there are still living organisms, and they can wake up, grow and multiply.”

It’s not only at the depths of the oceans that microbes have shown how hardy they can be. Scientists have also found microbes living in extreme conditions in Antarctica, as well as the driest deserts.

The study is published in Nature Communications.

 



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