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Ancient DNA from a teen girl reveals previously unknown group of humans – CNN

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(CNN)The bones of a teenage hunter-gatherer who died more than 7,000 years ago on the Indonesian island of Sulawesi tell the story of a previously unknown group of humans.

This distinct human lineage has never been found anywhere else in the world, according to new research.
The study published Wednesday in the journal Nature.
“We have discovered the first ancient human DNA in the island region between Asia and Australia, known as ‘Wallacea’, providing new insight into the genetic diversity and population history of early modern humans in this little understood part of the world,” said study coauthor Adam Brumm, a professor of archaeology at Griffith University’s Australian Research Centre for Human Evolution, via email.

The Leang Panninge cave is where researchers uncovered the remains a young hunter-gatherer from 7,000 years ago.

The first modern humans used the Wallacea islands, mainly Indonesian islands that include Sulawesi, Lombok and Flores, as they crossed from Eurasia to the Australian continent more than 50,000 years ago, researchers believe. The exact route or how they navigated this crossing, however, is unknown.
“They must have done so using relatively sophisticated watercraft of some kind, as there were no land bridges between the islands, even during the glacial peaks of the last ice age, when global sea levels were up to 140 meters (459 feet) lower than they are today,” Brumm said.
Tools and cave paintings have suggested that humans were living on these islands by 47,000 years ago, but the fossil record is sparse and ancient DNA degrades more rapidly in the tropical climate.
However, researchers uncovered the skeleton of a female between the ages of 17 and 18 in a cave on Sulawesi in 2015. Her remains were buried in the cave 7,200 years ago. She was part of the Toalean culture, only found in a pocket of Sulawesi’s southwestern peninsula. The cave is part of an archaeological site called Leang Panninge.
Maros points are associated with the Toalean culture.

Maros points are associated with the Toalean culture.

“The ‘Toaleans’ is the name archaeologists have given to a rather enigmatic culture of prehistoric hunter-gatherers that lived in the forested plains and mountains of South Sulawesi between around 8,000 years ago until roughly the fifth century AD,” said Brumm via email. “They made highly distinctive stone tools (including tiny, finely crafted arrowheads known as ‘Maros points’) that are not found anywhere else on the island or in wider Indonesia.”
The young hunter-gatherer is the first largely complete and well-preserved skeleton associated with the Toalean culture, Brumm said.
Lead study author Selina Carlhoff was able to retrieve DNA from the wedge-shaped petrous bone at the base of the skull.
“It was a major challenge, as the remains had been strongly degraded by the tropical climate,” said Carlhoff, also a doctoral candidate at the Max Planck Institute for the Science of Human History in Jena, Germany, in a statement.

Secrets hiding in DNA

The work to retrieve the genetic information was well worth it.
The young woman’s DNA showed that she descended from the first wave of modern humans to enter Wallacea 50,000 years ago. This was part of the initial colonization of “Greater Australia,” or the combined ice age landmass of Australia and New Guinea. These are the ancestors of present-day Indigenous Australians and Papuans, Brumm said.
Fragmentary remains of the girl's skull were used to retrieve her DNA.

Fragmentary remains of the girl's skull were used to retrieve her DNA.

And it turns out that the oldest genome traced to the Wallacea islands revealed something else: previously unknown ancient humans.
She also shares ancestry with a separate and distinct group from Asia who likely arrived after the colonization of Greater Australia — because modern Indigenous Australians and Papuans don’t share ancestry with this group, Brumm said.
“Previously, it was thought that the first time people with Asian genes entered Wallacea was around 3,500 years ago when Austronesian-speaking farmers from Neolithic Taiwan swept down through the Philippines and into Indonesia,” he said.
“It suggests that there might have been a distinct group of modern humans in this region that we really had no idea about up until now, as archaeological sites are so scarce in Wallacea and ancient skeletal remains are rare.”
No descendents of this lineage remain.
Her genome included another trace of an enigmatic and extinct group of humans: Denisovans. The handful of fossils signifying that these early humans ever existed are largely from Siberia and Tibet.
“The fact that their genes are found in the hunter-gatherers of Leang Panninge supports our earlier hypothesis that the Denisovans occupied a far larger geographical area” than previously understood, said study coauthor Johannes Krause, a professor of archaeogenetics at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, in a statement.
But when her DNA was compared with that of other hunter-gatherers who lived west of Wallacea at the same time, their DNA didn’t contain any traces of Denisovan DNA.
“The geographic distribution of Denisovans and modern humans may have overlapped in the Wallacea region. It may well be the key place where Denisova people and the ancestors of indigenous Australians and Papuans interbred,” said study coauthor Cosimo Posth, a professor at the University of Tübingen’s Senckenberg Centre for Human Evolution and Palaeoenvironment in Frankfurt, Germany, in a statement.
Researchers don’t know what happened to the Toalean culture, and this latest discovery is one piece of the puzzle as they try to understand the ancient genetic history of humans in southeast Asia. Brumm hopes that more ancient DNA from the Toalean people can be recovered to reveal its diversity “and its wider ancestral story.”

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Oldest human footprints in North America found in New Mexico – CTV News

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WASHINGTON —
Fossilized footprints discovered in New Mexico indicate that early humans were walking across North America around 23,000 years ago, researchers reported Thursday.

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

The findings may shed light on a mystery that has long intrigued scientists: When did people first arrive in the Americas, after dispersing from Africa and Asia?

Most scientists believe ancient migration came by way of a now-submerged land bridge that connected Asia to Alaska. Based on various evidence — including stone tools, fossil bones and genetic analysis — other researchers have offered a range of possible dates for human arrival in the Americas, from 13,000 to 26,000 years ago or more.

The current study provides a more solid baseline for when humans definitely were in North America, although they could have arrived even earlier, the authors say. Fossil footprints are more indisputable and direct evidence than “cultural artifacts, modified bones, or other more conventional fossils,” they wrote in the journal Science, which published the study Thursday.

“What we present here is evidence of a firm time and location,” they said.

Based on the size of the footprints, researchers believe that at least some were made by children and teenagers who lived during the last ice age.

David Bustos, the park’s resource program manager, spotted the first footprints in ancient wetlands in 2009. He and others found more in the park over the years.

“We knew they were old, but we had no way to date the prints before we discovered some with (seeds) on top,” he said Thursday.

Made of fine silt and clay, the footprints are fragile, so the researchers had to work quickly to gather samples, Bustos said.

“The only way we can save them is to record them — to take a lot of photos and make 3D models,” he said.

Earlier excavations in White Sands National Park have uncovered fossilized tracks left by a saber-toothed cat, dire wolf, Columbian mammoth and other ice age animals.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

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Inspiration4 Lift Off: SpaceX Launches World’s First All-Citizen Mission in Earth’s Orbit – Illinoisnewstoday.com

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Tampa, Florida (WFLA) — SpaceX made history on Wednesday night when it launched the world’s first all-civil mission to get going from the Space Coast, Florida.

The Inspiration4 mission took off from Launch Complex 39A at NASA’s Kennedy Space Center around 8:03 pm on Wednesday. The four crew members on the SpaceX Dragon spacecraft were launched onto a reusable Falcon 9 rocket and later separated from the spacecraft and landed on the drone.

The mission’s five-hour launch window began at 8:02 EST. The window was very large, as the crew was sent to orbit the Earth rather than the International Space Station, and therefore did not have such strict time constraints.

The crew is set to travel 350 miles above the surface of the Earth, about 100 miles higher than the International Space Station.

“This is important and historic, because it’s the best time humans have been in orbit since the Hubble Space Telescope mission,” said Benjireed, SpaceX’s manned spaceflight director.

(Photo provided by SpaceX)

The crew will spend three days in orbit to participate in research experiments on human health and performance. We hope that the results of our research will apply not only to future space flight, but also to human health here on Earth.

Inspiration4’s main goal is to provide and inspire support for St. Jude Children’s Research Hospital. They want to raise $ 200 million for St. Jude in a three-day mission.

According to SpaceX, each of the four members of the crew was chosen to represent the pillars of a mission of prosperity, generosity, hope and leadership. The Inspiration 4 crew and the pillars they represent are:

  • leadership: 38 years old Jared Isaacman – Founder and CEO of Shift4Payments
  • Hope: 29-year-old Haley Arseno – Doctor assistants and childhood cancer survivors treated with St. Jude
  • Generosity: 41 years old Chris Sembroski – Lockheed Martin US Air Force veteran and aerospace employee
  • prosperity: 51 years old Dr. Cyan Proctor – Entrepreneurs, educators, trained pilots, and the active voice of the space exploration community

SpaceX trained all four crew members as commercial astronauts on Falcon 9 and Dragon spacecraft. The crew was trained in orbital mechanics, microgravity, weightlessness, other stress tests, emergency preparedness, and spacesuit training.

The mission was funded by Isaacman in a private transaction with SpaceX. Isaacman has also invested $ 100 million towards a funding target for the St. Jude mission.

Inspiration4 Lift Off: SpaceX Launches World’s First All-Citizen Mission in Earth’s Orbit

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'Flying' microchips could ride the wind to track air pollution – Yahoo Movies Canada

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Researchers have created a winged microchip around the size of a sand grain that may be the smallest flying device yet made, Vice has reported. They’re designed to be carried around by the wind and could be used in numerous applications including disease and air pollution tracking, according to a paper published by Nature. At the same time, they could be made from biodegradable materials to prevent environmental contamination. 

The design of the flyers was inspired by spinning seeds from cottonwood and other trees. Those fall slowly by spinning like helicopters so they can be picked up by the wind and spread a long distance from the tree, increasing the range of the species. 

The team from Northwest University ran with that idea but made it better, and smaller. “We think we’ve beaten biology… we’ve been able to build structures that fall in a more stable trajectory at slower terminal velocities than equivalent seeds,” said lead Professor John A. Rogers. “The other thing… was that we were able to make these helicopter flyer structures that are much smaller than seeds you would see in the natural world.”  

They’re not so small that the aerodynamics starts to break down, though. “All of the advantages of the helicopter design begin to disappear below a certain length scale, so we pushed it all the way, as far as you can go or as physics would allow,” Rogers told Vice. “Below that size scale, everything looks and falls like a sphere.”

The devices are also large enough to carry electronics, sensors and power sources. The team tested multiple versions that could carry payloads like antenna so that they could wireless communicate with a smartphone or each other. Other sensors could monitor things like air acidity, water quality and solar radiation. 

The flyers are still concepts right now and not ready to deploy into the atmosphere, but the team plans to expand their findings with different designs. Key to that is the use of biodegradable materials so they wouldn’t persist in the environment. 

“We don’t think about these devices… as a permanent monitoring componentry but rather temporary ones that are addressing a particular need that’s of finite time duration,” Rogers said. “That’s the way that we’re envisioning things currently: you monitor for a month and then the devices die out, dissolve, and disappear, and maybe you have to redeploy them.”

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