Month: November 2024

SCIENCE: Fossilised droppings tell the story of dinosaurs rise to power

The contents of 200-million-year-old faeces and vomit are helping show how dinosaurs took over the world at the start of the Jurassic Period.

Well-preserved plants, bones, fish parts and even whole insects embedded in widely varying shapes and sizes of ancient animal droppings suggest that dinosaurs’ broad diets made them survivors in a changing ecosystem, compared with other groups of animals. That then led them to grow larger and ultimately establish their “dynasty on land”, says Martin Qvarnström at the University of Uppsala, Sweden.

Fossil evidence shows that the first dinosaurs – marked notably by hip joints that position the legs under the body like mammals, rather than sprawled out to the sides like lizards – appeared more than 230 million years ago during the Triassic Period. For tens of millions of years, these early dinosaurs blended into a landscape filled with many other kinds of reptiles. By about 200 million years ago, however, dinosaurs had essentially taken over the planet, while most other reptiles disappeared during the end-Triassic extinction at around that time.

What led to this domination has remained somewhat mysterious. Qvarnström and his colleagues suspected they might find significant clues hidden in bromalites – fossilised stool and vomit – from dinosaurs and other animals. So they gathered 532 examples stored in the Polish Geological Institute, which prior research groups had collected between 1996 and 2017 from eight sites in Poland.

The team estimated the age of each bromalite based on the layer of sediment it was found in and then used its size – ranging from a few millimetres to “pretty substantial faecal masses” – and shape to match it to the animal that probably produced it. The researchers then 3D scanned the fossils to explore their contents. “We realised that they’re packed with food remains,” says Qvarnström.

Coprolites, or fossilised dung, of herbivorous dinosaurs containing plant remains

Grzegorz Niedzwiedzki

Combined with known fossil records and past climate information, the researchers determined that the rise of dinosaurs occurred in several distinct steps. First, omnivorous ancestors of early dinosaurs started outnumbering the non-dinosaurs. Then, they evolved into the first meat-eating and plant-eating dinosaurs.

At that point, an increase in volcanic eruptions and shifts in tectonic plates led to flooding and the development of waterways. The resulting humidity and related changes in the climate seem to have triggered a greater range of plants, leading to the evolution of bigger and more diverse herbivore dinosaurs. Meanwhile, non-dinosaurs – like the 1-tonne, plant-eating dicynodont Lisowicia, whose faeces contained mainly conifer remains – were less able to adapt to the changing variety of vegetation.

As the herbivore dinosaurs grew bigger, so did their predators. When large carnivorous dinosaurs started to appear by the beginning of the Jurassic Period – about 30 million years after the first dinosaurs emerged – the transition to a dinosaur-dominated world was complete, says Qvarnström.

Last common ancestor of all life emerged far earlier than thought

“The study shows how climate mainly affected the dominant plants, which in turn gave opportunities for new herbivores at certain points,” says Michael Benton at the University of Bristol, UK, who wasn’t involved in the study.

Although it is hard to be sure that the researchers matched the droppings to the right animals, the findings nonetheless support earlier work from South America suggesting that dinosaur species were already significantly expanding prior to major climate change, he says. “But it took the end-Triassic mass extinction to put in place the final steps of the takeover.”

For Emma Dunne at Friedrich-Alexander University in Germany, the study helps answer long-standing questions about the rise of dinosaurs. “It’s not every day that you see fossil poop in such a high-impact journal,” says Dunne, who didn’t participate in the research. “It’s obviously funny, but it’s also really useful for understanding prehistoric environments. So if you think of early dinosaur evolution as kind of a jigsaw puzzle with missing pieces, it’s just thrown a huge chunk of new pieces in there.”

Source: https://www.newscientist.com/article/2458090-fossilised-droppings-tell-the-story-of-dinosaurs-rise-to-power/?utm_source=nsday&utm_medium=email&utm_campaign=nsday_281124&utm_term=Newsletter%20NSDAY_Daily

Scientists close in on cause of Alzheimer’s as they set sights on a common virus

Cutting-edge research suggests that a virus, which infects a million Americans each year, could raise your risk of dementia.

Stanford researchers found that shingles, a virus that causes a painful rash, could be increase your risk of developing Alzheimer’s, as people who received a vaccine for it were 20 percent less likely develop the disorder years later.

This emerging field of research, linking viruses that cause chickenpox, herpes and shingles to dementia, could be the key to making breakthroughs in the Alzheimer’s mystery, experts say.

Shingles is a viral infection that is caused by the same virus responsible for chickenpox. Sufferers get rashes of blisters that are painful and can be itchy

Researchers have only recently begun investigating the link between viruses, like varciella-zoster, which causes Shingles, and neurodegenerative disease. They are also examining the virus that causes herpes, which is in the same family as varciella-zoster

At random, as someone ages, the virus can reactivate, travelling along the nervous system to the skin according to Mayo Clinic. Doctors are unsure what causes the virus to reactivate, but it tends to happen in people as they age or get sick, which suggests that it could have do with a weakened immune system.

About one million people in the US get shingles each year, according to the CDC.

At the same time, 500,000 Americans are diagnosed with Alzheimer’s each year. Despite how common the disease is, research into the cause of the disease has made little progress over the past decades.

Dr Geldsetzer’s study, which represents a new theory for studying the disease, has yet to be peer reviewed by other scientists.

Still it has been made available online through the National Institute of Health since May 2023, and widely approved by other scientists in public.

The study looked at 300,000 health records of people born in Wales from 1925 to 1942 and tracked them over time – looking for their shingles vaccination, shingles diagnosis and dementia diagnosis.

In Wales, they designed shingle vaccination guidelines to have an age cutoff – based on data that showed the vaccination wasn’t effective in people over 80.

So the researchers had two groups to study – those born before 1933 who didn’t get vaccinated and those born after 1933 who did.

The groups were otherwise similar in age, pre-existing conditions and other health history.

They found that vaccination reduced risk of developing dementia by 20 percent in the seven years after getting the shot.

‘We’re looking at a causal effect. And it’s specific to dementia. There is something clearly going on here.’ Pascal Geldsetzer, Stanford University epidemiologist told STAT.

To make sure what they were seeing wasn’t specific to Wales alone, Dr Geldsetzer and his team then performed similar analysis in the United Kingdom and Australia, and found the same trend.

At the same time, researchers at Oxford University were performing studies that added to the theory linking shingles to Alzheimer’s.

A 2024 study published in the journal Nature looked at the health records of 200,000 Americans, seeing how they fared after receiving a form of shingles vaccine approved in 2017 called Shingrix.

A 2024 study showed the vaccine Shingrix was linked to a ‘significantly’ lower risk of dementia compared to Zostavax and jabs for other illnesses. This adds weight to other emerging research suggesting a link between shingles and dementia

The vaccine reduced risk of dementia by 17 percent for six years after it was delivered when compared to older shingles vaccines that were less effective.

Paul Harrison, the lead author and a professor of psychiatry at Oxford University told STAT: ‘I’ve always been a vaccine believer, but the Covid vaccine reinforced to me that there may be long-term benefits to vaccination beyond simply stopping short-term effects.’

Since the link between shingles and dementia is still so new, research has yet to explain how shingles may be causing some cases of the disease.

They think it may have to do with the period of time when the virus hides out in your nervous system after catching chicken pox.

Though it seems like the virus is harmless, research from the Netherlands suggests that your immune system is actively working to keep it in check while it camps out in the body.

When you age or get sick or the immune system is otherwise busy, this gives an opportunity for the virus to strike out in other parts of the body.

This includes the blood vessels, which neurologists from the University of Alabama has found can cause disruption to the blood flow of the brain.

Reducing or interrupting blood flow to the brain over a prolonged period of time can put the delicate cells of the brain under stress – causing damage or death that could add up over time, contributing to greater risk for dementia.

Whatever the cause of a virus-driven dementia might be, scientists like Dr Maria Nagel, a University of Colorado neurovirologist who studies shingles, are excited that researchers are looking into it.

For a long time, the majority of Alzheimer’s research and funding focused on just one theory.

So studying the link between neurodegeneration and viruses is a new opportunity, bringing new scientific minds to the puzzle that is Alzheimer’s.

Thinking about all the new people who have joined in Alzheimer’s research in recent years, Dr Nagel told STAT: ‘I really do believe that in the next 10 years or so we’re going to see huge strides in finding new mechanisms and finding new ways to try to slow things down.’

Source: https://www.dailymail.co.uk/health/article-13975165/scientists-alzheimers-cause-common-infection.html

INCREDIBLE SCIENCE: PANDO: The world’s largest and oldest tree is between 16,000-81,000 Years Old!!!

DNA analysis suggests Pando, a quaking aspen in Utah with thousands of stems connected by their roots, is between 16,000 and 81,000 years old

By James Woodford
1 November 2024

Some 47,000 trees in Utah’s Fishlake National Forest are in fact a single, ancient organism named Pando

George Rose/Getty Images

The world’s largest tree has been rigorously dated for the first time, confirming it is at least 16,000 years old.

Named Pando, the tree is a quaking aspen (Populus tremuloides) with around 47,000 stems connected by a root system that sprawls about 43 hectares in Utah’s Fishlake National Forest. It has long been thought to be among the most ancient living things on Earth, but scientists didn’t know for certain how old it is.

This is a paid article. Here is the source link: https://www.newscientist.com/article/2454482-worlds-largest-tree-is-also-among-the-oldest-living-organisms/?utm_source=nsday&utm_medium=email&utm_campaign=nsday_041124&utm_term=Newsletter%20NSDAY_Daily