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A study that attached cameras with suction cups to the backs of Antarctic whales has revealed never before seen feeding habits and social interactions.

Environment minister says federal government ‘would welcome any proposal to protect human life first’ after attack on surfer Laeticia Brouwer

The federal government would consider any strategies to prevent further shark attacks off Australia’s coast, following the death of teenager surfer Laeticia Brouwer.

“In light of the recent shark attack the commonwealth would welcome any proposal to protect human life first and foremost,” the federal environment minister, Josh Frydenberg, told the West Australian.

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A new resident off the coast of a Canadian town has turned it into a cool tourist spot.

Giant sloths: killed by rainy weather? Kamraman/Wikimedia Commons, CC BY-SA

Wet weather at the end of the last ice age appears to have helped drive the ecosystems of large grazing animals, such as mammoths and giant sloths, extinct across vast swathes of Eurasia and the Americas, according to our new research.

The study, published in Nature Ecology and Evolution today, shows that landscapes in many regions became suddenly wetter between 11,000 and 15,000 years ago, turning grasslands into peat bogs and forest, and ushering in the demise of many megafaunal species.

By examining the bone chemistry of megafauna fossils from Eurasia, North America and South America over the time leading up to the extinction, we found that all three continents experienced the same dramatic increase in moisture. This would have rapidly altered the grassland ecosystems that once covered a third of the globe.

The period after the world thawed from the most recent ice age is already very well studied, thanks largely to the tonnes of animal bones preserved in permafrost. The period is a goldmine for researchers – literally, given that many fossils were first found during gold prospecting operations.

Our work at the Australian Centre for Ancient DNA usually concerns genetic material from long-dead organisms. As a result, we have accrued a vast collection of bones from around the world during this period.

But we made our latest discovery by shifting our attention away from DNA and towards the nitrogen atoms preserved the fossils’ bone collagen.

Lead Author Tim Rabanus-Wallace hunts for megafaunal fossils in the Canadian permafrost in 2015. Julien Soubrier Chemical signatures

Nitrogen has two stable isotopes (atoms with the same number of protons but differing number of neutrons), called nitrogen-14 and nitrogen-15. Changes in environmental conditions can alter the ratio of these two isotopes in the soil. That, in turn, is reflected in the tissues of growing plants, and ultimately in the bones of the animals that eat those plants. In arid conditions, processes like evaporation preferentially remove the lighter nitrogen-14 from the soil. This contributes to a useful correlation seen in many grassland mammals: less nitrogen-14 in the bones means more moisture in the environment.

We studied 511 accurately dated bones, from species including bison, horses and llamas, and found that a pronounced spike in moisture occurred between 11,000 and 15,000 years ago, affecting grasslands in Europe, Siberia, North America, and South America.

Alan Cooper inspects ice age bones from the Yukon Palaeontology Program’s collection, Canada, 2015. Julien Soubrier

At the time of this moisture spike, dramatic changes were occurring on the landscapes. Giant, continent-sized ice sheets were collapsing and retreating, leaving lakes and rivers in their wake. Sea levels were rising, and altered wind and water currents were bringing rains to once-dry continental interiors.

The study shows that a peak in moisture occurred between the time of the ice sheets melting, and the invasion of new vegetation types such as peatlands (data shown from Canada and northern United States). http://nature.com/articles/doi:10.1038/s41559-017-0125

As a result, forests and peatlands were forming where grass, which specialises in dry environments, once dominated. Grasses are also specially adapted to tolerate grazing – in fact, they depend upon grazers to distribute nutrients and clear dead litter from the ground each season. Forest plants, on the other hand, produce toxic compounds specifically to deter herbivores. For decades, researchers have discussed the idea that the invading forests drove the grassland communities into collapse.

Our new study provides the crime scene’s smoking gun. Not only was moisture affecting the grassland mammals during the forest invasion and the subsequent extinctions, but this was happening right around the globe.

Extinction rethink

This discovery prompts a rethink on some of the key mysteries in the extinction event, such as the curious case of Africa. Many of Africa’s megafauna — elephants, wildebeest, hippopotamus, and so on — escaped the extinction events, and unlike their counterparts on other continents have survived to this day.

It has been argued that this is because African megafauna evolved alongside humans, and were naturally wary of human hunters. However, this argument cannot explain the pronounced phase of extinctions in Europe. Neanderthals have existed there for at least 200,000 years, while anatomically modern humans arrive around 43,000 years ago.

We suggest instead that the moisture-driven extinction hypothesis provides a much better explanation. Africa’s position astride the Equator means that its central forested monsoon belt has always been surrounded by continuous stretches of grassland, which graded into the deserts of the north and south. It was the persistence of these grasslands that allowed the local megafauna to survive relatively intact.

Our study may also offers insights into the question of how the current climate change might affect today’s ecosystems.

Understanding how climate changes affected ecosystems in the past is imperative to making informed predictions about how climate changes may influence ecosystems in the future. The consequences of human-induced global warming are often depicted using images of droughts and famines. But our discovery is a reminder that all rapid environmental changes — wet as well as dry — can cause dramatic changes in biological communities and ecosystems.

In this case, warming expressed itself not through parched drought but through centuries of persistent English drizzle, with rain, slush and grey skies. It seems like a rather unpleasant way to go.

Alan Cooper receives funding from the Australian Research Council

Matthew Wooller receives funding from US National Science Foundation

Tim Rabanus-Wallace does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.

When a team of scientists went to the Yukon to study the Slims River, all they found was a "skinny lake".

Unlikely coalition of fossil fuel firms, environmental groups and Republicans are calling on president to stay despite his pledge to ‘cancel’ agreement

Donald Trump’s aides have abruptly postponed a meeting to determine whether the US should remain in the Paris climate agreement, with an unlikely coalition of fossil fuel firms, environmental groups and some Republicans calling on the president to stick with the deal.

Trump’s top advisers were set to meet on Tuesday to provide the president with a recommendation ahead of a G7 meeting in May. However, a White House official said the meeting had been postponed due to conflicting schedules. It is unclear when it will now take place.

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From Harrogate to Tokyo cherry blossom is in full bloom at the peak of spring

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Some of them may know where to find food but not how to access it while others know how to get at it but not where it is hidden.

The BBC's Sir David Attenborough will show people "natural treasures" within the new Google Earth.

The hands of the Doomsday Clock currently stand at two-and-a-half-minutes to midnight. Professor Ray Pierrehumbert of Oxford University and the Bulletin of Atomic Scientists explains why support for science and the global March for Science on 22 April is crucial

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Good management of mega-constellations of spacecraft can avoid polluting the orbital environment.

March for Science on 22 April will see scientists and supporters at more than 500 locations stand up for evidence-based thinking

Scientists and science supporters will take to the streets in a global March for Science on 22 April . What began as a small Facebook group in the US capital, Washington DC has spiralled into a global phenomenon that will now see marches and other events in more than 500 locations around the world, from Seattle to Seoul.

It is great news that so many people are prepared to stand up and defend the need for evidence-based thinking and the scientific method. But it is also a sad comment on our times that a March for Science is needed at all. Post-truth populism has infected democracies around the world, scientific objectivity is under threat from multiple sources and there seems a real danger of falling into a modern dystopian dark age.

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Scientists are ditching their labs for the streets in a mass protest against the Trump administration’s war on facts, but will the effort resonate with skeptics?

On Saturday, thousands of scientists are set to abandon the cloistered neutrality of their laboratories to plunge into the the political fray against Donald Trump in what will likely be the largest ever protest by science advocates.

The March for Science, a demonstration modeled in part on January’s huge Women’s March, will inundate Washington DC’s national mall with a jumble of marine biologists, birdwatchers, climate researchers and others enraged by what they see as an assault by Trump’s administration upon evidence-based thinking and scientists themselves.

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The two brown bears were found by Ukrainian charity Four Paws.

Based on reports, an infrastructure fund of Australia-based Macquarie Group has acquired a large solar portfolio from India’s Hindustan Power.

Nuvation Energy announces that their new 11-60 VDC battery management system.

A year ago, NSW was considered the worst place to invest in wind and solar energy in the country. Now the Coalition state government has a plan that could rival Labor states in its ambition.

Claxton, Norfolk At Thorpe Hall near Haddiscoe, 340 pairs of rooks once nested, but this spring there is not one

Assessing the rook population in the Yare valley has long been a favourite ritual of my springs. Since the nests are coarse bundles of sticks in the bare treetops it is easy to combine the serious census work with the season’s wider pleasures: the sounds of first chiffchaffs or blackcaps, the lemon wings of male brimstone butterflies, and the year’s first glamorous colour from primroses, marsh marigolds and walls of blackthorn blossom.

However, by the time I reached the third of my 30 rookeries, I sensed that this year would be different. A site that had once held 100 nests was completely empty. Thereafter, each old place revealed the new story of absence.

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Scientists find live specimens of the giant shipworm, described as "rare and enigmatic".

Nano-Nouvelle says lithium-ion battery boosting technology is ready for use on commercial battery production lines.