Latest news with #UniversityofTübingen
Yahoo
2 days ago
- General
- Yahoo
Ancient DNA reveals mysterious Indigenous group from Colombia that disappeared 2,000 years ago
When you buy through links on our articles, Future and its syndication partners may earn a commission. A new analysis of ancient DNA from hunter-gatherers who lived millennia to centuries ago has revealed a previously unknown genetic lineage of humans who lived in what is now Colombia. People of this lineage lived near present-day Bogotá around 6,000 years ago but disappeared around 4,000 years later, according to a study published May 28 in the journal Science Advances. The findings could shed light on major cultural changes that occurred during that time. It's thought that the first Americans journeyed along the Bering Land Bridge from Asia during the last ice age and arrived in North America at least 23,000 years ago, according to trackways found at White Sands National Park in New Mexico. It's still debated when the first people arrived in South America, but there's evidence of people at the site of Monte Verde II, in Chile, from 14,550 years ago. Some of the early Indigenous people who reached South America settled in the Altiplano, a plateau near what is now Bogotá. This region underwent several cultural shifts during the Early and Middle Holocene (11,700 to 4,000 years ago), and researchers already knew about the development of a type of ceramic pottery that emerged during the Herrera period beginning about 2,800 years ago. But how this technology came to the area is still a matter of debate. To investigate ancient population movements in the region, researchers sequenced genomes using samples from the bones and teeth of 21 skeletons from five archaeological sites in the Altiplano spanning a period of 5,500 years. These included seven genomes from a site known as Checua dating back 6,000 years, nine from the Herrera period around 2,000 years ago, three from the Muisca period, whose remains date to 1,200 to 500 years ago, and two from Guane populations north of Bogotá about 530 years ago. "These are the first ancient human genomes from Colombia ever to be published," study co-author Cosimo Posth, a paleogeneticist at the University of Tübingen in Germany, said in a statement. The genomes from the Checua site belonged to a relatively small group of hunter-gatherers, the team found. Their DNA isn't particularly similar to that of Indigenous North American groups, nor to any ancient or modern populations in Central or South America. "Our results show that the Checua individuals derive from the earliest population that spread and differentiated across South America very rapidly," study co-author Kim-Louise Krettek, a doctoral student at the Senckenberg Center for Human Evolution and Paleoenvironment at the University of Tübingen, said in the statement. But some 4,000 years later, that population had completely vanished. Evidence of their DNA wasn't present in later groups who inhabited the region, either. "We couldn't find descendants of these early hunter-gatherers of the Colombian high plains — the genes were not passed on," Krettek said. "That means in the area around Bogotá there was a complete exchange of the population." The findings suggest that cultural changes that occurred at the start of the Herrera period, such as the more widespread use of ceramics, were brought into the region by migrating groups from Central America into South America sometime between 6,000 and 2,000 years ago. "In addition to technological developments such as ceramics, the people of this second migration probably also brought the Chibchan languages into what is present-day Colombia," study co-author Andrea Casas-Vargas, a geneticist at the National University of Colombia, said in the statement. "Branches of this language family are still spoken in Central America today." Chibchan speakers were widespread in the Altiplano at the time of European contact, and genetic markers linked to people who spoke Chibchan languages first appeared there 2,000 years ago. RELATED STORIES —Newly discovered 'ghost' lineage linked to ancient mystery population in Tibet, DNA study finds —'Mystery population' of human ancestors gave us 20% of our genes and may have boosted our brain function —Unknown human lineage lived in 'Green Sahara' 7,000 years ago, ancient DNA reveals The Chibchan-related ancestry may have spread and mixed with other groups on multiple occasions. The genetic composition of later Altiplano individuals is more similar to that of pre-Hispanic individuals from Panama than to Indigenous Colombians, suggesting some mixing in Colombia. Ancient remains from Venezuela also carry some Chibchan-related ancestry, though they aren't as closely linked to ancient Colombians. This suggests the possibility of multiple Chibchan language expansions into South America. Future studies could involve sequencing more ancient genomes in the Altiplano and nearby regions, the researchers wrote in the study. Such research might help narrow down when Central American populations arrived in the region and how widespread they became.
Yahoo
5 days ago
- General
- Yahoo
Traces of Mysterious Ancient Human Population Discovered in Colombia
Colombia sits on the land through which Homo sapiens first spread from Central America to South America more than 14,500 years ago, making it a crucial population gateway. Researchers have now found evidence of a previously unknown people who once lived there. Specifically, an international team has traced back 6,000 years of history, based on DNA analysis of 21 sets of carefully chosen human remains. The remains were collected from five sites across the Altiplano plateau, in central Colombia. These DNA records reveal a fascinating timeline, including the existence of an ancient population with genetics unrelated to any modern descendants – a group of people who may have been some of the earliest settlers in South America, but who subsequently disappeared completely. "We couldn't find descendants of these early hunter-gatherers of the Colombian high plains – the genes were not passed on," says anthropologist Kim-Louise Krettek, from the University of Tübingen, in Germany. "That means in the area around Bogotá there was a complete exchange of the population." DNA contains the genetic instructions we need to grow into the people we are, with contributions from parents, grandparents, and generations before them. By studying it, scientists can work out links between generations – and see how these generations moved and evolved over time. While one group was settled in the Colombian region around 6,000 years ago, a different community, with completely separate genetics, called the area home starting about 2,000 years ago. These people, who would've most likely spoken Chibchan languages, do have known genetic links to modern groups from the lower part of Central America. This later group also represents a cultural shift, from the hunter-gatherers of the original population, to people who were skilled in pottery-making and more sophisticated types of agriculture. It seems that these people stayed in place until settlers from Europe started arriving in the 16th century. "That genetic traces of the original population disappear completely is unusual, especially in South America," says geneticist Andrea Casas-Vargas, from the National University of Colombia. What happened to this newly discovered group, established 6,000 years ago, is something the researchers don't speculate on – though the usual causes of conflict or disease may be responsible. It's something future studies could look into. Even with many questions remaining unanswered though, the research offers some valuable insight into the history of South America and some of the earliest people to venture down from the north. Earlier studies have suggested that the story of indigenous people in the region may be more complex than previously thought, and genetic links to South America have connected its people to places as far away as Australia. With Colombia sitting right on the land bridge between South America and the continent to the north of it, however, it's a particularly important place to study – and it likely has more secrets to give up yet. "These are the first ancient human genomes from Colombia ever to be published," says anthropologist Cosimo Posth, from the University of Tübingen. The research has been published in Science Advances. Here's How to Detect a Fake Smile, According to Science What Makes Someone a Narcissist? Scientists Just Found a Big Clue Remains of 3,000-Year-Old Maya City Discovered in Guatemala
Hindustan Times
22-05-2025
- Science
- Hindustan Times
Forget compass, crows can spot geometric flaws without Math tools: Latest study
A crow doesn't need a compass or a protractor to know when something looks off. That's the latest revelation from a study in Science Advances, which shows that carrion crows can spot geometric regularity- symmetry, parallel lines, and right angles. Two birds, no math class, and yet they could tell when a shape wasn't spot on. We humans have long considered geometric intuition our exclusive domain. The ability to recognise when shapes follow orderly principles and to instinctively grasp concepts like symmetry and perpendicularity has been described as a unique human talent. Geometry is a way of thinking found across cultures, even in people with no formal education. This basic sense of shape regularity underpins centuries of human thought, from Euclid's Elements to modern design. But that story may need a rewrite, or at least a footnote. Researchers at the University of Tübingen in Germany trained two crows to play a visual game on a touchscreen. Six shapes would appear, and the task was to peck the one that didn't belong. At first, the differences were obvious --- five identical shapes and one distinctly different one. Then came the real test --- sets of four-sided shapes that looked almost identical. Squares, parallelograms, trapezoids, and versions with just one angle or edge slightly off. Despite having never encountered this type of geometric challenge before, the crows performed well. They didn't just identify the intruder; they showed a pattern of performance that closely mirrors how humans perceive shapes. The birds were most accurate when the base shapes were regular. Their accuracy dropped as the regularity declined, suggesting their sensitivity to symmetry and parallelism matches our own. Even their mistakes resembled ours. Like many human subjects, the crows struggled most with the rhombus, a shape that often slips past our intuitive sense of irregularity. Also Read: Two crow deaths at Gorakhpur zoo increase bird flu worries What makes this finding especially striking is that other species have failed at similar tasks. Baboons, despite being far more closely related to us, couldn't learn to detect these geometric differences, even after extensive training. Yet crows, whose lineage diverged from ours more than 300 million years ago, succeeded spontaneously. Crows have been surprising people for years. They belong to a remarkably intelligent bird family, the corvids, known for solving problems that stump other animals. Crows craft tools, solve multistep puzzles, remember human faces for years, and even grasp the concept of zero. In one well-known experiment, a New Caledonian crow bent a straight wire into a hook to retrieve food from a narrow tube --- a task that requires abstract reasoning and defeats many young children. The crows in this study were familiar with visual tasks and interacted with a touchscreen to earn treats. But this experiment tested their understanding of shape regularity, something far more abstract. To rule out chance, the researchers rotated and resized the shapes, randomized their positions, and analysed dozens of trials per bird. The crows still got it right. Birds navigate complex environments, build nests with structural precision, and use spatial memory to cache thousands of food items. A natural grasp of shape, angle, and spatial relationships would be useful. What we consider abstract mathematics might, for them, be a survival skill. Also Read: Caw of the wild: Meet the Mumbai crows with an Instagram following The researchers don't claim that crows are unique- only that they're the first non-human animals shown to have this ability. Their findings open the door to testing other intelligent species such as parrots, dolphins, and elephants that might also possess this form of visual reasoning. If birds and humans both show this ability, despite their vast evolutionary distance, then perhaps geometric intuition isn't a human invention. It may be older, more deeply rooted, and not limited to humans and crows. Anirban Mahapatra is a scientist and author, most recently of When The Drugs Don't Work: The Hidden Pandemic That Could End Medicine. The views expressed are personal. Get 360° coverage—from daily headlines to 100 year archives.
Time of India
24-04-2025
- Science
- Time of India
THIS ancient animal hunted and ate the dinosaurs, reveals study
Deinosuchus, one of the biggest crocodilians that ever lived, had a body as long as a school bus and teeth the size of bananas. From 82 to 75 million years ago, this giant predator lived in rivers and estuaries across North America. Though it had a broad snout like an alligator, scientists now say Deinosuchus was something else entirely. According to a new study published Wednesday in Communications Biology, Deinosuchus was not part of the alligator family after all. The research team used fossil evidence and DNA from living crocodilians to build a new family tree. It shows that Deinosuchus is more closely related to crocodiles than to alligators. Modern crocodiles have salt glands that help them survive in seawater. Deinosuchus had those glands, too, but alligators do not. That detail is key. Salt tolerance would have allowed Deinosuchus to swim across the Western Interior Seaway—a vast sea that once split North America in two during a time of high global sea levels. Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like Co-Founder of Google Brain, Andrew Ng, Recommends: 5 Books For Turning Your Life Around Blinkist: Andrew Ng's Reading List Undo 'With salt glands, Deinosuchus could go where alligators couldn't,' said Dr. Márton Rabi, a senior study author and lecturer at the University of Tübingen in Germany. 'We are talking about an absolutely monstrous animal. Definitely around 8 meters (26 feet) or more total body length,' Rabi told CNN. Toothmarks on dinosaur bones show Deinosuchus hunted or scavenged them. 'No one was safe in these wetlands when Deinosuchus was around,' Rabi said. Fossils of Deinosuchus have been found on both sides of the ancient seaway. The largest species, Deinosuchus riograndensis, lived along the eastern edge of an island called Laramidia, which made up less than a third of the North American landmass. The other large landmass was known as Appalachia. For a long time, scientists believed Deinosuchus was part of the alligatoroid group. But this didn't make sense. Alligators only live in freshwater today. How could Deinosuchus cross a sea more than 1,000 kilometers wide? One theory was that early alligators once had salt glands and later lost them. But that idea had little evidence and depended on Deinosuchus being an alligator relative. The fossil record didn't support the idea that Deinosuchus spread across North America before the sea formed, either. 'The picture wasn't very coherent,' Rabi said. To fix that, the researchers added data from extinct crocodilians that hadn't been used in previous studies. These 'missing links' helped clarify the evolution of salt tolerance and other traits. 'Our analysis found that saltwater tolerance is a fairly ancient trait of many crocodilians, and was secondarily lost in the alligatoroids,' Rabi said. The researchers also found that the first alligators were smaller than other crocodilians of the time. They didn't grow large until about 34 million years ago—long after Deinosuchus lived. Rabi said the smaller size of early alligatoroids is another clue that Deinosuchus was not one of them. 'Dwarfism in early alligatoroids was another clue that giant Deinosuchus was no 'greater alligator.'' The study also found that huge crocodilians like Deinosuchus evolved again and again over the past 120 million years, even during ice ages. According to Rabi, 'Giant crocs are more like the norm of any time.'
Express Tribune
24-04-2025
- Science
- Express Tribune
Saltwater power turned ancient terror crocodile into a dinosaur-eating giant
Listen to article A colossal, extinct reptile that preyed on dinosaurs had a broad, alligator-like snout—but what truly set it apart was a feature modern alligators lack: the ability to tolerate salt water. Deinosuchus was among the largest crocodilian species ever recorded, stretching nearly the length of a bus and armed with banana-sized teeth. Between 82 and 75 million years ago, this apex predator roamed the rivers and estuaries of ancient North America. Its skull was both wide and elongated, capped with a distinctive bony bulge unseen in other crocodilians. Fossilised bones from the Cretaceous period bearing toothmarks suggest Deinosuchus fed on or scavenged dinosaurs. Though its name means 'terror crocodile,' Deinosuchus was long considered more closely related to alligators and was often nicknamed the 'greater alligator.' Previous research grouped it with ancient and modern alligator species. But fresh fossil evidence, combined with genetic data from living crocodilians proved that deinosuchus belong to the crocodilian family tree. Scientists now say Deinosuchus was not an alligatoroid at all. Unlike its freshwater cousins, it retained the salt glands found in early crocodilians—organs that help regulate salt levels by excreting excess sodium chloride. These are still present in modern crocodiles but absent in today's alligators. This salt tolerance likely gave Deinosuchus a powerful edge during the Late Cretaceous, allowing it to move freely through the Western Interior Seaway—a vast inland sea that split North America during a period of high global sea levels. The predator's range may have extended across both sides of the ancient seaway, including coastal regions along the Atlantic. The newly proposed crocodilian family tree provides deeper understanding of how some species adjusted to environmental changes while others vanished. Thanks to its salt glands, Deinosuchus could colonise ecosystems that its alligator-like relatives could not. With access to coastal marshes filled with large prey, it became one of the most dominant predators of its time—an enormous reptile capable of feeding on nearly anything that crossed its path. 'When Deinosuchus was around, nothing was safe in these wetlands,' said Dr. Márton Rabi, the study's senior author and a lecturer at the University of Tübingen's Institute of Geosciences. 'This was an absolutely monstrous animal—easily eight metres long or more.' To build a clearer picture of crocodilian evolution, researchers incorporated fossil data from previously unsampled extinct species—key 'missing links' that helped clarify long-misunderstood relationships. These additions allowed the team to track when certain traits, such as saltwater tolerance, first emerged within the group. 'Our findings show that salt tolerance is an ancient trait in crocodilians, one that was later lost in alligatoroids,' said study co-author Dr Márton Rabi. This adaptation would have been especially useful as shifting climates altered landscapes, added Dr Evon Hekkala, a biological sciences professor at Fordham University, who was not involved in the research. 'This ecological advantage likely gave some crocodile lineages a better shot at survival during periods of major environmental change, such as rising sea levels,' Hekkala said. The team also reconstructed the crocodilian family tree using genetic data from living species. Their analysis showed that early alligators were considerably smaller than other crocodilians of the time. The evolution of the larger body sizes seen in today's alligators only began around 34 million years ago, likely as a result of climate cooling and the extinction of their competitors. At the time Deinosuchus lived, however, it stood out as a giant among much smaller alligatoroid relatives. This, combined with new insights into early dwarfism in the group, supports the conclusion that Deinosuchus branched off from the family tree before alligatoroids began to evolve. 'Giant crocs are more like the norm — of any time,' Rabi said.
