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Fossils: Plankton changed diets to survive dinosaur-killing asteroid

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fossils plankton changed diets to survive dinosaur killing asteroid

To survive the impact that eradicated the dinosaurs 66 million years ago, plankton changed their diets from absorbing sunlight to eating bacteria, a study found.

Researchers from the UK and the US studied how fossils of the microscopic algae changed in the rock record from before and after the asteroid collision.

Before the asteroid hit, such microorganisms acquired their energy via photosynthesis — but the dust cloud from the impact blocked out the sunlight.

The plankton that survived also had the ability to hunt and consume bacterial prey — a capacity evidenced by holes in their shells for the ‘tails’ that let them swim.

In this way, these species survived the mass extinction event that killed off not only the dinosaurs but also around three-quarters of all plant and animal species.

To survive the impact that eradicated the dinosaurs 66 million years ago, plankton changed their diets from absorbing sunlight to eating bacteria, a study found. Pictured, the skeletons of tiny plankton after the impact event had holes out of which flagella — thread-like motive structures — would have extended to allow the organisms to hunt prey in the water column

To survive the impact that eradicated the dinosaurs 66 million years ago, plankton changed their diets from absorbing sunlight to eating bacteria, a study found. Pictured, the skeletons of tiny plankton after the impact event had holes out of which flagella — thread-like motive structures — would have extended to allow the organisms to hunt prey in the water column

To survive the impact that eradicated the dinosaurs 66 million years ago, plankton changed their diets from absorbing sunlight to eating bacteria, a study found. Pictured, the skeletons of tiny plankton after the impact event had holes out of which flagella — thread-like motive structures — would have extended to allow the organisms to hunt prey in the water column

‘This event came closest to wiping out all multicellular life on this planet, at least in the ocean,’ said paper author and earth scientist Andrew Ridgwell of the University of California, Riverside.

‘If you remove algae — which form the base of the food chain — everything else should die,’ he added.

‘We wanted to know how Earth’s oceans avoided that fate, and how our modern marine ecosystem re-evolved after such a catastrophe.’

Professor Ridgwell and colleagues analysed tiny fossils of algae that had been preserved in clay-rich sediments for the last 66 million years.

They used evolutionary computer models to simulate how the microorganisms would have behaved before and after the mass extinction event.

Before the asteroid, plankton species relied exclusively on sunlight for energy — but the skies were blocked out by dust and debris following the impact event.

‘This blackout or shutdown of primary productivity would have been felt across all of Earth’s ecosystems,’ said paper author and palaeoceanographer Samantha Gibbs of the University of Southampton.

‘The Cretaceous–Paleogene (K–Pg) event is distinct from all other mass extinctions that have shaped the history of life.’

This difference, she explained, comes ‘both in its rapidity — related to an instantaneous impact event — and its darkness kill mechanism, which shook the foundations of the food chains.’

Before the K–Pg boundary, plankton skeletons — which experts refer to as ‘coccospheres’ — found in the fossil record looked notably different to those preserved from after the catastrophe, the team said. 

A large hole in the coccospheres from after the mass extinction suggests that the microorganisms had flagella — thin, tail-like structures, whose whipping motion would have allowed the algae to swim around.

Before the K–Pg boundary, plankton skeletons — which experts refer to as 'coccospheres' — found in the fossil record looked notably different to those preserved from after the catastrophe, the team said. A large hole in the coccospheres from after the mass extinction suggests that the microorganisms had flagella — thin, tail-like structures, whose whipping motion would have allowed the algae to swim around and grab bacteria with its 'haptonema'

Before the K–Pg boundary, plankton skeletons — which experts refer to as 'coccospheres' — found in the fossil record looked notably different to those preserved from after the catastrophe, the team said. A large hole in the coccospheres from after the mass extinction suggests that the microorganisms had flagella — thin, tail-like structures, whose whipping motion would have allowed the algae to swim around and grab bacteria with its 'haptonema'

Before the K–Pg boundary, plankton skeletons — which experts refer to as ‘coccospheres’ — found in the fossil record looked notably different to those preserved from after the catastrophe, the team said. A large hole in the coccospheres from after the mass extinction suggests that the microorganisms had flagella — thin, tail-like structures, whose whipping motion would have allowed the algae to swim around and grab bacteria with its ‘haptonema’

The presence of flagella suggests that the plankton had developed the ability to capture food for energy in the absence of sunlight, the researchers said.

‘The only reason you need to move is to get your prey,’ noted Professor Ridgwell.

Modern relatives of these ancient creatures also have chloroplasts, which allow them to harness sunlight and make food from carbon dioxide and water.

This ability to survive both by feeding on other organisms and through photosynthesis is called mixotrophy.

‘Those species that were lost at the mass extinction show no evidence of a mixotrophic lifestyle and were likely to be completely reliant on sunlight and photosynthesis,’ Dr Gibbs said.

‘Fossils following the K–Pg extinction show that mixotrophy dominated.’

‘Our model indicates this is because of the exceptional abundance of small prey cells — most likely surviving bacteria — and reduced numbers of larger ‘grazers’ in the post-extinction oceans.’

Surviving plankton expanded from coastal shelves into the open ocean once the dust had settled and the darkness cleared.

In this environment, they became a dominant life form for the next million years and helped rebuild the food chain.

‘The results illustrate both the extreme adaptability of ocean plankton and their capacity to rapidly evolve,’ said Professor Ridgwell.

‘Yet also, for plants with a generation time of just a single day, that you are always only a year of darkness away from extinction.’

‘Mixotrophy was both the means of initial survival and then an advantage after the post-asteroid darkness lifted because of the abundant small pretty cells — likely survivor cyanobacteria.’

‘It is the ultimate Halloween story — when the lights go out, everyone starts eating each other,’ he quipped.

The full findings of the study were published in the journal Science Advances.

KILLING OFF THE DINOSAURS: HOW A CITY-SIZED ASTEROID WIPED OUT 75 PER CENT OF ALL ANIMAL AND PLANT SPECIES

Around 65 million years ago non-avian dinosaurs were wiped out and more than half the world’s species were obliterated.

This mass extinction paved the way for the rise of mammals and the appearance of humans.

The Chicxulub asteroid is often cited as a potential cause of the Cretaceous-Paleogene extinction event.

The asteroid slammed into a shallow sea in what is now the Gulf of Mexico.

The collision released a huge dust and soot cloud that triggered global climate change, wiping out 75 per cent of all animal and plant species.

Researchers claim that the soot necessary for such a global catastrophe could only have come from a direct impact on rocks in shallow water around Mexico, which are especially rich in hydrocarbons.

Within 10 hours of the impact, a massive tsunami waved ripped through the Gulf coast, experts believe.

Around 65 million years ago non-avian dinosaurs were wiped out and more than half the world's species were obliterated. The Chicxulub asteroid is often cited as a potential cause of the Cretaceous-Paleogene extinction event (stock image)

Around 65 million years ago non-avian dinosaurs were wiped out and more than half the world's species were obliterated. The Chicxulub asteroid is often cited as a potential cause of the Cretaceous-Paleogene extinction event (stock image)

Around 65 million years ago non-avian dinosaurs were wiped out and more than half the world’s species were obliterated. The Chicxulub asteroid is often cited as a potential cause of the Cretaceous-Paleogene extinction event (stock image)

This caused earthquakes and landslides in areas as far as Argentina.

But while the waves and eruptions were  The creatures living at the time were not just suffering from the waves – the heat was much worse.

While investigating the event researchers found small particles of rock and other debris that was shot into the air when the asteroid crashed.

Called spherules, these small particles covered the planet with a thick layer of soot.

Experts explain that losing the light from the sun caused a complete collapse in the aquatic system.

This is because the phytoplankton base of almost all aquatic food chains would have been eliminated.

It’s believed that the more than 180 million years of evolution that brought the world to the Cretaceous point was destroyed in less than the lifetime of a Tyrannosaurus rex, which is about 20 to 30 years.

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Pollution regulations to reduce dirty air have saved 1.5 BILLION birds in the US over 40 years

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pollution regulations to reduce dirty air have saved 1 5 billion birds in the us over 40 years

US pollution controls aren’t just good for the atmosphere, they’re saving our winged friends, too.

Ozone gasses, a leading contributor to smog, is linked tied to health problems in both humans and avians. 

A new study found that regulations intended to reduce the pollution have also slowed the decline of bird populations in the US.  

Scientists at Cornell and the University of Oregon tracked changes in bird abundance, ozone emissions and regulation status across the nation over a 15 year period.

Extrapolating their findings, they found caps on ozone emissions may have saved as many as 1.5 billion birds in the past 40 years, – equal to 20 percent of all birds in the United States today.

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A new Cornell study on EPA policies shows

A new Cornell study on EPA policies shows

A new Cornell study on EPA regulations shows efforts to curb ozone production have saved more than a billion birds in the last 40 years. The gas is not only harmful to the animals’ respiratory system, it can kill off the plants and insects they eat

Ozone occurs naturally, but automobiles and power plants have contributed to a significant increase in its production. 

While it’s necessary in the upper atmosphere to protect us from the sun’s ultraviolet rays, at ground level ozone causes smog and contributes to respiratory and cardiovascular disease, especially in the young and the elderly.

Numerous studies have connected ozone at levels currently found in many urban areas to low birth weights, asthma, and even early death.  

It’s also detrimental to bird life, especially the small migratory birds — like sparrows and finches — that make up more than three-quarters of all North American species. 

Ozone is a leading ingredient in smog and has been linked to respiratory illness, cardiovascular disease and low birth weight, among other health risks

Ozone is a leading ingredient in smog and has been linked to respiratory illness, cardiovascular disease and low birth weight, among other health risks

Ozone is a leading ingredient in smog and has been linked to respiratory illness, cardiovascular disease and low birth weight, among other health risks 

As with humans, it impacts their respiratory system — but it can also kill off the plants and insects that serve as their chief food sources.

‘Not surprisingly, birds that cannot access high-quality habitat or food resources are less likely to survive or reproduce successfully,’ said Amanda Rodewald, director of Cornell’s Center for Avian Population Studies and co-author of a new report in Proceedings of the National Academy of Sciences.

‘The good news here is that environmental policies intended to protect human health return important benefits for birds, too.’

To get an idea of how regulations have impacted this country’s winged population, Rodewald and environmental economist Ivan Rudik combined pollution data with environmental policies and bird observations from the Cornell Lab of Ornithology, tracking.

A separate 2019 study by the Cornell Lab of Ornithology showed that North American bird populations have declined by nearly 3 billion birds since 1970

A separate 2019 study by the Cornell Lab of Ornithology showed that North American bird populations have declined by nearly 3 billion birds since 1970

A separate 2019 study by the Cornell Lab of Ornithology showed that North American bird populations have declined by nearly 3 billion birds since 1970

They tracked monthly changes in bird abundance, air quality, and regulation status over 15 years in more than 3,200 counties.

The team focused on the EPA’s NOx (nitrogen oxide) Budget Trading Program, a cap-and-trade initiative launched in 2003 to reduce ozone emissions from power plants and other large industrial sources during the summer months.

A separate 2019 study by the Cornell Lab of Ornithology showed that North American bird populations have declined by nearly 3 billion birds since 1970.

Without existing environmental regulations, Rodewald and Rudik say, an estimated 1.5 billion more birds would have died.

‘Our research shows that the benefits of environmental regulation have likely been underestimated,’ said Rudik. 

‘Reducing pollution has positive impacts in unexpected places and provides an additional policy lever for conservation efforts.’  

The Trump administration has been criticized for rolling back dozens of environmental regulations,

In June 2017, then-EPA administrator Scott Pruitt announced he was delaying enforcement of an Obama-era regulation governing ozone emissions, The New York Times reports.

In August of that year, one day after 16 state attorneys general filed a lawsuit claiming the agency was violating the Clean Air Act, Pruitt reversed his decision and said he would enforce the policy.

Heather McTeer Toney, a former regional EPA administrator under the Obama administration, is among a short-list of candidates being considered to lead the agency under President-elect Biden, Reuters reports. 

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Trove of arrows dating back 6,000 years are discovered in Norway after drastic amounts of ice melts 

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trove of arrows dating back 6000 years are discovered in norway after drastic amounts of ice melts

A veritable treasure trove of ancient artifacts has been discovered in an Norwegian ice patch that climate change has caused to melt.

Researchers found nearly 70 arrow shafts, plus shoes, textiles and reindeer bones on a mountainside in Jotunheimen, about 240 miles from Oslo.

Based on radiocarbon dating, the oldest arrows are from around 4100 BC, with the most recent dating from 1300 AD.

While the discovery confirms the region was a popular spot for reindeer hunting millennia ago, it upends conventional wisdom about how ice patches can be used to interpret the historical record.

Archaeologists had assumed the ice preserved items as they were deposited, sealing them in place and providing a timeline — with older relics on the bottom and newer ones on top.

But the different amounts of weathering on the objects, as well as their seemingly random order, counters the theory that ice patches are like photographs, presenting a preserved image of the past.

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A 1,300-year-old arrow discovered at Langfonne. A record-setting 68 arrows were found in all in the Norwegian ice patch, some with their arrowheads still attached

A 1,300-year-old arrow discovered at Langfonne. A record-setting 68 arrows were found in all in the Norwegian ice patch, some with their arrowheads still attached

A 1,300-year-old arrow discovered at Langfonne. A record-setting 68 arrows were found in all in the Norwegian ice patch, some with their arrowheads still attached

A record-setting 68 arrows were found in all, some with their arrowheads still attached.

The heads were made from a variety of materials — iron, quartzite, slate, mussel shell and even bone.

 Several still had the twine and tar used to affix them to a wooden shaft.

The biggest number of arrows dated to 700 through 750 AD, but the oldest were some 6,000 years old.

A 4,000-year-old arrowhead made from quartzite. Other arrow tips were made from slate, bone and sharpened mussel shell.

A 4,000-year-old arrowhead made from quartzite. Other arrow tips were made from slate, bone and sharpened mussel shell.

A 4,000-year-old arrowhead made from quartzite. Other arrow tips were made from slate, bone and sharpened mussel shell.

A 4,000-year-old arrow shaft found on the ice. Based on radiocarbon dating, the oldest arrows are from around 4100 BC, with the most recent dating from 1300 AD

A 4,000-year-old arrow shaft found on the ice. Based on radiocarbon dating, the oldest arrows are from around 4100 BC, with the most recent dating from 1300 AD

A 4,000-year-old arrow shaft found on the ice. Based on radiocarbon dating, the oldest arrows are from around 4100 BC, with the most recent dating from 1300 AD

An aerial photo of Langfonne's three separate main ice patches.  Because of global warming, it is now less than 30 percent of the size it was just two decades ago, according to Pilø

An aerial photo of Langfonne's three separate main ice patches.  Because of global warming, it is now less than 30 percent of the size it was just two decades ago, according to Pilø

An aerial photo of Langfonne’s three separate main ice patches.  Because of global warming, it is now less than 30 percent of the size it was just two decades ago, according to Pilø

‘This is earlier than finds from any other ice site in Northern Europe,’ according to archaeologist Lars Holger Pilø, ‘and about 800 years earlier than Ötzi,’ the 5,100-year-old ice mummy found in the Tyrolean Alps in 1991.

Other artifacts from Langfonne include a well-preserved shoe from more than 3,000 years ago and fabric Pilø says may have been used to package meat.   

The Langfonne ice patch was first uncovered in 2006, when hiker Reidar Marstein discovered a leather shoe from the early Bronze Age there and reported it to Pilø.

At the time, researchers had assumed new layers of snow added to a patch, like strata in the earth, with older layers near the core and newer layers near the surface.

Map of ice sites in Innlandet County. The Langfonne ice patch was first discovered in 2006

Map of ice sites in Innlandet County. The Langfonne ice patch was first discovered in 2006

Map of ice sites in Innlandet County. The Langfonne ice patch was first discovered in 2006

Examples of arrows found at Langfonne. Left shows the nock end of an arrow and right shows a partially preserved arrow shaft in four fragments at the bottom left of the picture

Examples of arrows found at Langfonne. Left shows the nock end of an arrow and right shows a partially preserved arrow shaft in four fragments at the bottom left of the picture

Examples of arrows found at Langfonne. Left shows the nock end of an arrow and right shows a partially preserved arrow shaft in four fragments at the bottom left of the picture

‘The idea was, ice is like a time machine. Anything that lands on it stays there and is protected,’ Pilø, a researcher with the Innlandet County Council Cultural Heritage Department, told National Geographic.

But a closer examination showed the ice melted and re-froze numerous times over the millennia, shifting the arrows around from their original locations.

In addition, if the patch was acting like a time machine, older artifacts should have been just as well preserved as newer ones.

Archaeologists taking samples and artifacts from Langfonne. Analysis of the arrows found on the site disprove the theory that ice patches present a perfectly preserved image of history 'like a time machine'

Archaeologists taking samples and artifacts from Langfonne. Analysis of the arrows found on the site disprove the theory that ice patches present a perfectly preserved image of history 'like a time machine'

Archaeologists taking samples and artifacts from Langfonne. Analysis of the arrows found on the site disprove the theory that ice patches present a perfectly preserved image of history ‘like a time machine’

Instead, the Neolithic arrows were broken and heavily weathered, suggesting they had been exposed to the elements at various times.

The 14th century arrows, though, ‘looked as though they were shot just yesterday,’ National Geographic reported. 

‘This led to a suspicion that something had happened to them while inside the ice,’ Pilø wrote in a blog post on Wednesday.

A view of Langfonne ice patch, from the top of the mountain

A view of Langfonne ice patch, from the top of the mountain

A view of Langfonne ice patch, from the top of the mountain

In a new report in the journal Holocene, Pilø says that makes it hard to glean certain information about the people who used these artifacts.

‘The ice is an artifact-preserver but it is also at the same time a destroyer of history,’ he told Nat Geo.

New discoveries may still present themselves as Langfonne, now split into three smaller patches, continues to thaw.

Its melting is part of a worldwide pattern of retreating mountain glaciers linked to global warming, Pilø wrote.

‘Langfonne has retreated dramatically in the last two decades. It is now less than 30 percent of the size it was 20 years ago. This retreat is clearly visible in the landscape.’

And the patch is only 10 percent of what it was at its height, he said, during the ‘Little Ice Age’ that took place between the 15th and 20th century.

This post first appeared on dailymail.co.uk

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When will Earth be eco-friendly? Most Americans believe the world will be greener by 2042

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when will earth be eco friendly most americans believe the world will be greener by 2042

This year may have been rough, but as 2020 comes to a close many Americans are looking forward to a better future – and a greener one.

A new survey reveals 59 percent foresee a ‘completely environmentally friendly’ Earth by year 2042, but the majority understands that it is only possible if we all work together.

The idea of going green is producing zero waste and running on renewable energy, along with swapping cars for a bicycle or walking and adopting a plant-based diet.

Among ways to create a better world, 70 percent of the respondents also believe climate change is the single biggest threat facing humanity.

A new survey reveals 59 percent foresee a ‘completely environmentally friendly' Earth by year 2042, but the majority understands that it is only possible if we all work together. The idea of going green is producing zero waste and running on renewable energy

A new survey reveals 59 percent foresee a ‘completely environmentally friendly' Earth by year 2042, but the majority understands that it is only possible if we all work together. The idea of going green is producing zero waste and running on renewable energy

A new survey reveals 59 percent foresee a ‘completely environmentally friendly’ Earth by year 2042, but the majority understands that it is only possible if we all work together. The idea of going green is producing zero waste and running on renewable energy

The study was conducted by Cool Effect, which survey 2,000 adults living in the US to understand how Americans feel about climate change and the steps they are willing to take to combat its effects, according to StudyFinds.

The top answers for what a completely environmentally friendly world was a tie of 57 percent for zero waste and using nothing but renewable energy.

Approximately 52 percent said banning single-use plastics, which is a law in eight states currently.

Nearly half of the respondents suggested people bike or walk to their destination instead of driving, while some Americans think an eco-friendly life is a more plant-based diet.

Respondents also suggested swapping cars for a bicycle or walking and adopting a plant-based diet. Among ways to create a better world, 70 percent of the respondents also believe climate change is the single biggest threat facing humanity

Respondents also suggested swapping cars for a bicycle or walking and adopting a plant-based diet. Among ways to create a better world, 70 percent of the respondents also believe climate change is the single biggest threat facing humanity

Respondents also suggested swapping cars for a bicycle or walking and adopting a plant-based diet. Among ways to create a better world, 70 percent of the respondents also believe climate change is the single biggest threat facing humanity

A finding that came out of the new survey shows that a third of those polled have actually switched careers for a more eco-friendly company and 68 percent have or are willing to pack up their lives and move to a more sustainable city

However, although these Americans are willing to fight for a greener world, the research found that many of them are not aware of their own personal carbon footprint – only 36 percent could produce an answer.

The survey also suggests that Americans tend to ignore their personal responsibility  and feel their own carbon footprint is not making an impact on the warming world.

A previous study from 2019 found that some Americans overestimate their contribution – both findings suggests they need to meet in the middle  

However, data from the United States Department of Energy shows the average American emits roughly 17 tons of carbon per year – survey respondents said it was only 11.4 tons.

This post first appeared on dailymail.co.uk

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