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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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Just 3% of the world’s land remains ecologically intact with healthy populations of all its original animals and undisturbed habitat, a study suggests.

These fragments of wilderness undamaged by human activities are mainly in parts of the Amazon and Congo tropical forests, east Siberian and northern Canadian forests and tundra, and the Sahara. Invasive alien species including cats, foxes, rabbits, goats and camels have had a major impact on native species in Australia, with the study finding no intact areas left.

The researchers suggest reintroducing a small number of important species to some damaged areas, such as elephants or wolves – a move that could restore up to 20% of the world’s land to ecological intactness.

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Reforestation is one of the ways we have of trying to mitigate climate change, but choosing where to plant trees is a more complex decision than you might think. This is why researchers have now come up with an interactive map showing the best spots to reforest in the US.

It's called the Reforestation Hub, and it color codes counties to show the reforestation opportunity or potential for success in each area. The team behind the map is hoping it proves a valuable resource for the government and individual conservation agencies.

"Often the information we need to make informed decisions about where to deploy reforestation already exists, it's just scattered across a lot of different locations," says forest restoration scientist Susan Cook-Patton, from the Nature Conservancy organization.

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Three million face masks are thought to be thrown away every minute, research suggests.

In June 2020, researchers at the University of Aveiro in Portugal estimated that 129 billion face masks are used monthly across the world.

Experts at the University of Denmark have described the worrying statistic, which amounts to three million face masks a minute, as a ‘ticking time bomb’.

In the paper, titled Preventing masks from becoming the next plastic problem, scientists said the world must ‘urgently recognise this potential environmental threat’.

One key factor which could be contributing to the problem is that face coverings are a new phenomenon in most countries across the world. While we are quite used to recycling items such as plastic bottles, there is no official guidance on mask recycling. Researchers said this makes it more likely that they would be disposed of as solid waste.

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Planet Earth is losing 1.2 trillion tons of ice every single year, a new study has confirmed.

The grim milestone was published in the journal Cryosphere, revealing that the loss of ice is up by nearly 60% since 1994, thanks to the acceleration of global warming.

Between the years of 1994 and 2017, Earth lost 28 trillion tons of ice – enough to cover the UK with a 300ft deep layer sheet – a sum which is only set to continue rising as the Earth’s atmosphere continues to rise in temperature.

Meanwhile, sea levels have risen by 1.3 inches globally since 1994.

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The number of wild bee species recorded by an international database of life on earth has declined by a quarter since 1990, according to a global analysis of bee declines.

Researchers analyzed bee records from museums, universities and citizen scientists collated by the Global Biodiversity Information Facility, (GBIF) a global, government-funded network providing open-access data on biodiversity.

They found a steep decline in bee species being recorded since 1990, with approximately 25 percent fewer species reported between 2006 and 2015 than before the 1990s.

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