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For now, life is flourishing on our oxygen-rich planet, but Earth wasn't always that way – and scientists have predicted that, in the future, the atmosphere will revert back to one that's rich in methane and low in oxygen.

This probably won't happen for another billion years or so. But when the change comes, it's going to happen fairly rapidly, the study from earlier this year suggests.

This shift will take the planet back to something like the state it was in before what's known as the Great Oxidation Event (GOE) around 2.4 billion years ago.

What's more, the researchers behind the new study say that atmospheric oxygen is unlikely to be a permanent feature of habitable worlds in general, which has implications for our efforts to detect signs of life further out in the Universe.

"The model projects that a deoxygenation of the atmosphere, with atmospheric O2 dropping sharply to levels reminiscent of the Archaean Earth, will most probably be triggered before the inception of moist greenhouse conditions in Earth's climate system and before the extensive loss of surface water from the atmosphere," wrote the researchers in their published paper.

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While no one enjoys seeing carefully nurtured crops destroyed by hordes of hungry insects, the most common way to prevent it – the use of insecticides – is causing massive ecological problems.

Some are wreaking havoc on bee populations globally, killing birds and piling onto the challenges already faced by endangered species. Thankfully, insecticides are generally only in our food at low levels, but they do harm humans who are highly exposed to them too, like the workers growing our crops.

They also destroy predatory insect populations, which just makes the problem of crop pests worse in the long term - with fewer pest enemies around to keep their numbers in check.

One alternative that researchers and farmers have been putting to the test is the use of predatory insects to control the problematic plant eaters. However, this approach, known as biological control, has its own challenges.

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Single-use plastic plates and cutlery, and polystyrene cups will be banned in England under government plans, as it seeks to reduce the plastic polluting the environment.

A public consultation will launch in the autumn and the ban could be in place in a couple of years. The move was welcomed by campaigners, but they said overall progress on cutting plastic waste was “snail-paced”, with the EU having banned these items and others in July.

The average person uses 18 throwaway plastic plates and 37 single-use knives, forks and spoons each year, according to ministers, while the durability of plastic litter means it kills more than a million birds and 100,000 sea mammals and turtles every year around the world.

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The world broke a major record last month — although it has little reason to brag about the milestone.

July was the hottest month ever recorded, according to data released Friday by the National Oceanic and Atmospheric Administration — an “unenviable distinction” that could ratchet up anxiety about climate change.

“In this case, first place is the worst place to be,” NOAA Administrator Rick Spinrad said in a statement. “July is typically the world’s warmest month of the year, but July 2021 outdid itself as the hottest July and month ever recorded.”

He said the record “adds to the disturbing and disruptive path that climate change has set for the globe.”

The world broke a major record last month — although it has little reason to brag about the milestone.

July was the hottest month ever recorded, according to data released Friday by the National Oceanic and Atmospheric Administration — an “unenviable distinction” that could ratchet up anxiety about climate change.

“In this case, first place is the worst place to be,” NOAA Administrator Rick Spinrad said in a statement. “July is typically the world’s warmest month of the year, but July 2021 outdid itself as the hottest July and month ever recorded.”

He said the record “adds to the disturbing and disruptive path that climate change has set for the globe.”

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Some types of bacteria are hardy enough to survive in the most inhospitable of conditions – and that includes concrete, as a new study proves. Not only can microbes survive in this dry, inhospitable building material, they can actually thrive there too.

The research shows that bacteria could provide early warnings of moisture-induced alkali-silica reactions (or 'concrete cancer') that can lead to structural deficiencies. Further down the line, we might even be able to harness bacteria to repair damage to bridges and roads.

While previous studies had already established that bacteria are able to make their homes inside concrete, here the scientists wanted to take a closer look at which microbes were present and how their communities might change over time.

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After a decade of work, a biologist has shown that a horizontal offshoot of the thale cress plant is a body part all its own: the cantil.

The machinery of life is dazzlingly complex. To try to make sense of it, researchers have spent decades focusing on so-called model organisms: creatures that are easy to study in the lab and share key features with many other forms of life. This model group includes the lab mouse, the fruit fly, and an unassuming weed called thale cress, or Arabidopsis thaliana.

Model organisms are among the best understood lifeforms in the world. So imagine scientists’ surprise when, after a decade of work, a dogged plant biologist found a brand-new organ on thale cress, hiding in plain sight.

The newfound organ, described today in the journal Development, is a horizontal arm that juts off the main stem of Arabidopsis and acts as a support for the pedicel, the small stalk that leads to the base of a flower. Extending from the main stem of the plant, the part is reminiscent of the structural support known as a cantilever, leading researchers to name the organs “cantils.”

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Populations of the insect, which once swarmed across the United States on their annual migrations from Mexico to Canada, have fallen off a cliff over the last century. California’s butterflies are on the brink of extinction, while eastern monarchs, which fly up the Great Plains or over to Maine, have declined 80 percent.

In their winter habitats in the mountains of northern Mexico, the monarchs cluster together so tightly that their populations are tabulated not by the number of individual butterflies, but by the total area they cover. The long term restoration goal for the eastern monarchs is a stable winter population of 6 hectares—an area of about 11 football fields.

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A huge ice block has broken off from western Antarctica into the Weddell Sea, becoming the largest iceberg in the world and earning the name A-76.

It is the latest in a series of large ice blocks to dislodge in a region acutely vulnerable to climate change, although scientists said in this case it appeared to be part of a natural polar cycle.

Slightly larger than the Spanish island of Majorca, A-76 had been monitored by scientists since May 13 when it began to separate from the Ronne Ice Shelf, according to the US National Ice Center.

The iceberg, measuring around 170 kilometres (105 miles) long and 25 kilometres wide, with an area of 4,320 square kilometres is now floating in the Weddell Sea.

It joins previous world's largest title holder A-23A—approximately 3,880 sq km in size—which has remained in the same area since 1986.

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Our world is hugged by complex layers of gases that make up the atmosphere. They protect and nurture all life as we know it. Now, we're shrinking an entire one of those layers – the stratosphere – thanks to the profound impacts we are having on our planet.

An alarming new study has found that the thickness of the stratosphere has already shrunk by 400 meters (1,312 feet) since 1980. While local decreases in the stratosphere's thickness have previously been reported, this is the first examination of this phenomenon on a global scale.

"It is shocking," one of the research team, University of Vigo Earth physicist Juan Añel told Damian Carrington at The Guardian. "This proves we are messing with the atmosphere up to 60 kilometers."

Enveloping the sky around 20 to 60 kilometers (12 to 37 miles) above us, the stratosphere blankets the atmospheric layer we're breathing (the troposphere). Few clouds venture this high and only the occasional birds. It holds the all-important ozone layer, which we've already wreaked havoc upon through our emissions of CFCs.

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Lightning could be a much more important atmospheric cleanser than previously thought, according to a new analysis of historical measurements gathered from a storm-chasing airplane back in 2012 – data which were originally thought to be inaccurate.

While some of the air-scrubbing qualities of lightning bolts are already well understood – in particular the creation of nitric oxide and hydroxide that can flush out various greenhouse gases from the sky – there's a lot more going on here, according to the new research.

It appears that both lightning bolts and the weaker, invisible electrical charges around them can produce the pollutant-catching oxidants hydroxyl (OH) and hydroperoxyl (HO2), which can also remove gases such as methane and carbon monoxide from the atmosphere.

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Glaciers are melting more quickly, losing 31 per cent more snow and ice per year than they did 15 years ago, according to three-dimensional satellite measurements of all the world's mountain glaciers.

Using 20 years of recently declassified satellite data, scientists calculated that the world's 220,000 mountain glaciers have been losing more than 298 billion metric tonnes of ice and snow per year since 2015, according to a study in Wednesday's journal Nature.

The annual melt rate from 2015 to 2019 is 71 billion metric tonnes more per year than it was from 2000 to 2004.

Global thinning rates, different than volume of water lost, doubled in the last 20 years.

Half the world's glacial loss is coming from the United States and Canada.

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Like members of a street gang, male dolphins summon their buddies when it comes time to raid and pillage—or, in their case, to capture and defend females in heat. A new study reveals they do this by learning the “names,” or signature whistles, of their closest allies—sometimes more than a dozen animals—and remembering who consistently cooperated with them in the past. The findings indicate dolphins have a concept of team membership—previously seen only in humans—and may help reveal how they maintain such intricate and tight-knit societies.

“It is a ground-breaking study,” says Luke Rendell, a behavioral ecologist at the University of St. Andrews who was not involved with the research. The work adds evidence to the idea that dolphins evolved large brains to navigate their complex social environments.

Male dolphins typically cooperate as a pair or trio, in what researchers call a “first-order alliance.” These small groups work together to find and corral a fertile female. Males also cooperate in second-order alliances comprised of as many as 14 dolphins; these defend against rival groups attempting to steal the female. Some second-order alliances join together in even larger third-order alliances, providing males in these groups with even better chances of having allies nearby should rivals attack.

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