![]() “As far as we can tell,” DePalma says in an email, “the majority of the articulated carcasses are from animals that were either killed when they were encapsulated by the muddy sediment, or very shortly prior as part of the same violent inundation surge event.” The disturbance sloshed local bodies of water in a phenomenon called a seiche-similar to water flowing back and forth in a bathtub-tossing fish and other organisms around in the wave. According to DePalma and colleagues, seismic waves emanating from the asteroid impact reached the Tanis area within minutes. At the present moment, interesting data are presented in the paper while other elements of the story that could be data are, for the moment, only rumors.”Īs for the paper itself, the details are part of a broader picture of what transpired 66 million years ago in western North America, along the margins of a vanishing seaway that was draining off the continent at the time. “This is a sloppy way to conduct science and it leaves open many questions. “Unfortunately, many interesting aspects of this study appear only in the New Yorker article and not in the scientific paper,” says Kirk Johnson, director of the Smithsonian’s National Museum of Natural History. Mass of articulated fish from the Tanis inundation surge deposit. The only dinosaur fossil mentioned in the paper is a weathered hip fragment, but the study is nevertheless causing a stir as a window into the extreme effects caused by the asteroid impact. ![]() That research, published by DePalma and colleagues, was released Monday in the Proceedings of the National Academy of Science. Many paleontologists were quick to raise an eyebrow at the findings presented in the New Yorker, however, particularly because some of the claims in the article are not mentioned in a scientific paper about the site. Also embedded in the rock and debris, the New Yorker reported, are delicately preserved fossil fish, marine organisms far from the nearest sea, ancient plants, prehistoric mammals, and, perhaps most significantly, dinosaur bones, eggs and even feathers. Excavated and studied by University of Kansas graduate student Robert DePalma and a team of international collaborators, the site contains glassy spherules of material believed to have come from the impact event, thousands of miles away. The fossil assemblage, nicknamed Tanis after the real-life ancient Egyptian city referenced in Raiders of the Lost Ark, was first described in an article the New Yorker. Now a fossil site in North Dakota is causing a new stir, said to document the last minutes and hours of the dinosaurian reign. This line in the stone is also the marker for the end of the Age of Dinosaurs and the beginning of the Age of Mammals, a shift that has been intensely debated and studied for decades. The distinctive rock layer it left behind, spiked with an element called iridium often found in asteroids and meteorites, marks the end of the Cretaceous period and the beginning of the Paleogene, known by experts as the K/Pg boundary. The Chicxulub impact was a catastrophic transition into a new world. ![]() Who perished, and who survived, set the stage for the next 66 million years-including our own origin 300,000 years ago. Even groups that survived, like mammals and lizards, suffered dramatic die-offs in the aftermath. The non-avian dinosaurs, pterosaurs and coil-shelled squid cousins called ammonites disappeared completely. Sixty-six million years ago, an immense asteroid smacked into what is now the Yucatán Peninsula of Mexico, triggering global devastation and the world’s fifth mass extinction. It may be considered one of the worst days in the history of life on Earth.
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