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Oldest human footprints in North America found in New Mexico – Al Jazeera English

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Fossilised footprints dating 23,000 years push back the known date the continent was colonised by thousands of years.

Footprints dating back 23,000 years have been discovered in the United States, suggesting humans settled North America long before the end of the last Ice Age, according to researchers.

The findings announced on Thursday push back the date at which the continent was colonised by its first inhabitants by thousands of years.

The footprints were left in mud on the banks of a long-since dried up lake, which is now part of a New Mexico desert.

Sediment filled the indentations and hardened into rock, protecting evidence of our ancient relatives, and giving scientists a detailed insight into their lives.

The first footprints were found in a dry lake bed in White Sands National Park in 2009. Scientists at the United States Geological Survey recently analysed seeds stuck in the footprints to determine their approximate age, ranging from 22,800 to 21,130 years ago.

“Many tracks appear to be those of teenagers and children; large adult footprints are less frequent,” write the authors of the study published in the American journal Science.

“One hypothesis for this is the division of labour, in which adults are involved in skilled tasks whereas ‘fetching and carrying’ are delegated to teenagers.

“Children accompany the teenagers, and collectively they leave a higher number of footprints.”

Researchers also found tracks left by mammoths, prehistoric wolves, and even giant sloths, which appear to have been approximately at the same time as the humans visited the lake.

Historic findings

The Americas were the last continent to be reached by humanity.

For decades, the most commonly accepted theory has been that settlers came to North America from eastern Siberia across a land bridge – the present-day Bering Strait.

From Alaska, they headed south to kinder climes.

Archaeological evidence, including spearheads used to kill mammoths, has long suggested a 13,500-year-old settlement associated with so-called Clovis culture – named after a town in New Mexico.

This was considered the continent’s first civilisation, and the forerunner of groups that became known as Native Americans.

However, the notion of Clovis culture has been challenged over the past 20 years, with new discoveries that have pushed back the age of the first settlements.

Generally, even this pushed-back estimate of the age of the first settlements had not been more than 16,000 years, after the end of the so-called “last glacial maximum” – the period when ice sheets were at their most widespread.

This episode, which lasted until about 20,000 years ago, is crucial because it is believed that with ice covering much of the northern parts of the continent, human migration from Asia into North America and beyond would have been very difficult.

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Guilt, grief and anxiety as young people fear for climate’s future

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Overwhelmed, sad, guilty are some of the emotions young people say they feel when they think of  Climate Change and their concerns world leaders will fail to tackle it.

Broadly referred to as climate anxiety, research has stacked up to measure its prevalence ahead of the U.N. talks in Glasgow, which begin at the end of the month to thrash out how to put the 2015 Paris Agreement on curbing climate change into effect.

One of the biggest studies to date, funded by Avaaz, an online campaign network, and led by Britain’s University of Bath, surveyed 10,000 young people aged 16-25 years in 10 countries. It published its results in September.

It found around three quarters of those surveyed considered the future frightening, while a lack of action by governments and industry left 45% experiencing climate anxiety and distress that affected their daily lives and functioning.

Elouise Mayall, an ecology student at Britain’s University of East Anglia and member of the UK Youth Climate Coalition, told Reuters she had felt guilty and overwhelmed.

“What I’d be left with is maybe the sense of shame, like, ‘how dare you still want lovely things when the world is ending and you don’t even know if you’re going to have a safe world to grow old in’.”

She spoke of conflicting emotions.

“You might have sadness, there might be fear, there might be a kind of overwhelm,” she said. “And maybe even sometimes a quite like wild optimism.”

Caroline Hickman, a psychotherapist and lecturer at the University of Bath and one of the co-authors of the research published in September, is working to help young people manage climate-related emotions.

“They’re growing up with the grief and the fear and the anxiety about the future,” she told Reuters.

“SENSE OF MEANING”

London-based psychiatrist Alastair Santhouse sees climate change, as well as COVID-19, as potentially adding to the burden, especially for those pre-disposed to  anxiety .

For now, climate anxiety alone does not normally require psychiatric help. Painful as it is, it can be positive, provided it does not get out of control.

“Some anxiety about climate change is motivating. It’s just a question of how much anxiety is motivating and how much is unacceptable,” said Santhouse, author of a book that tackles how health services struggle to cope with complex mental issues.

“The worry is that as climate change sets in, there will be a more clear cut mental health impact,” he added.

Among some of the world’s communities that are already the most vulnerable, extreme weather events can also cause problems such as post traumatic stress disorder.

Leading climate campaigner Greta Thunberg, 18, has experienced severe climate anxiety.

“It’s a quite natural response, because, as you see, as the world is today, that no one seems to care about what’s happening, I think it’s only human to feel that way,” she said.

For now, however, she is hopeful because she is doing everything she possibly can.

“When you take action, you also get a sense of meaning that something is happening. If you want to get rid of that anxiety, you can take action against it,” she said.

 

(Reporting by Barbara Lewis; Editing by Alison Williams)

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Rocket failure mars U.S. hypersonic weapon test as others succeed

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The Pentagon ‘s hypersonic weapon programs suffered a setback on Thursday when a booster rocket carrying a hypersonic weapon failed, people briefed on the test result said.

The test was intended to validate aspects of one of the Pentagon’s hypersonic glide vehicles in development, two of the people said.

Hypersonic glide vehicles are launched from a rocket in the upper atmosphere before gliding to a target at speeds of more than five times the speed of sound, or about 3,853 miles (6,200 kilometers) per hour.

In a separate series of tests conducted on Wednesday, the U.S. Navy and Army tested hypersonic weapon component prototypes. That test successfully “demonstrated advanced hypersonic technologies, capabilities, and prototype systems in a realistic operating environment,” the Pentagon said in a statement.

The United States and its global rivals have quickened their pace to build hypersonic weapons – the next generation of arms that rob adversaries of reaction time and traditional defeat mechanisms.

U.S. President Joe Biden expressed concern on Wednesday about Chinese hypersonic missiles, days after a media report that Beijing had tested a nuclear-capable hypersonic glide weapon.

Glide bodies are different from their air-breathing hypersonic weapon cousins which use scramjet engine technology and the vehicle’s high speed to forcibly compress incoming air before combustion to enable sustained flight at hypersonic speeds. An air-breathing hypersonic weapon was successfully tested in September.

Companies such as Lockheed Martin and Raytheon Technologies are working to develop the hypersonic weapon capability for the United States.

(Reporting by Mike Stone and Idrees Ali in Washington; Editing by Sandra Maler)

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Patagonian fossils show Jurassic dinosaur had the herd mentality | Saltwire – SaltWire Network

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By Will Dunham

(Reuters) – A vast trove of fossils unearthed in Argentina’s southern Patagonia region is offering the oldest-known evidence that some dinosaurs thrived in a complex and well-organized herd structure, with adults caring for the young and sharing a communal nesting ground.

Scientists said on Thursday the fossils include more than 100 dinosaur eggs and the bones of about 80 juveniles and adults of a Jurassic Period plant-eating species called Mussaurus patagonicus, including 20 remarkably complete skeletons. The animals experienced a mass-death event, probably caused by a drought, and their bodies were subsequently buried by wind-blown dust, the researchers said.

“It is a pretty dramatic scene from 193 million years ago that was frozen in time,” said paleontologist Diego Pol of the Egidio Feruglio Paleontological Museum in Trelew, Argentina, who led the research published in the journal Scientific Reports.

Mussaurus, which grew to about 20 feet (6 meters) long and about 1.5 tons, possessed a long neck and tail, with a small head. It was bipedal as an adult but newborns were quadrupedal. Mussaurus lived early in the Jurassic, the second of three periods comprising the age of dinosaurs. It was a relatively large beast for its time – much bigger than contemporaneous meat-eating dinosaurs. Dinosaurs became true giants later in the Jurassic.

“The site is one of a kind,” Pol said. “It preserves a dinosaur nesting ground including delicate and tiny dinosaur skeletons as well as eggs with embryos inside. The specimens we have found showed that herd behavior was present in long-necked dinosaurs since their early history. These were social animals, and we think this may be an important factor to explain their success.”

The animals were found to have been grouped by age at the time of their deaths, with hatchlings and eggs in one area while skeletons of juveniles were clustered nearby. The eggs were arranged in layers within trenches. Adults were found alone or in pairs.

This phenomenon, called “age segregation,” signals a complex social structure, the researchers said, including adults that foraged for meals and cared for the young. The researchers suspect that members of the herd returned to the same spot during successive seasons to form breeding colonies.

“The young were staying with the adults at least until they reached adulthood. It could be that they stayed in the same herd after reaching adulthood, but we don’t have information to corroborate that hypothesis,” said paleontologist and study co-author Vincent Fernandez of the Natural History Museum in London.

Herd behavior also can protect young and vulnerable individuals from attack by predators.

“It’s a strategy for the survival of a species,” Fernandez said.

The oldest previous evidence for dinosaur herd behavior was from about 150 million years ago.

The nesting ground was situated on the dry margins of a lake featuring ferns and conifers in a warm but seasonal climate. The eggs are about the size of a chicken’s, and the skeleton of a hatchling fits in the palm of a human hand. The adults got as heavy as a hippo.

A scanning method called high-resolution X-ray computed tomography confirmed that the embryos inside the eggs indeed were of Mussaurus.

Mussaurus was a type of dinosaur called a sauropodomorph, which represented the first great success story among herbivorous dinosaurs. Sauropodomorphs were an evolutionary forerunner to a group called sauropods known for long necks and tails and four pillar-like legs.

The largest land animals in Earth’s history were the sauropod successors of sauropodomorphs, as exemplified by a later denizen of Patagonia called Argentinosaurus that reached perhaps 118 feet (36 meters) in length and upwards of 70 tons.

(Reporting by Will Dunham in Washington, Editing by Rosalba O’Brien)

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