It seemed to be settled that a bloody great asteroid hitting the Yucatan wiped out the dinosaurs all those millions of non-biblical years ago. Then all these doubts reared their reptilian heads. Maybe it was multiple asteroids, maybe it was a mighty volcanic episode, or something else entirely. Finally it seems we’re back to believing it was that one massive rock.
“It's official: The extinction of the dinosaurs and a host of other species 65.5 million years ago was caused by a massive asteroid that crashed into the Gulf of Mexico, creating worldwide havoc, an international team of researchers said Thursday. The 7.5-mile-wide asteroid was traveling at a speed about 10 times that of a rifle bullet when it hit, releasing a billion times more energy than the Hiroshima atom bomb. The impact blew dirt and rock around the world, set massive wildfires, knocked down forests worldwide, triggered massive tsunamis and earthquakes of magnitude 11 or larger and even caused parts of the continent to slip into the ocean. Those events wiped out more than half of all species on Earth in what has been called the greatest extinction event of all time. The species lost included not only the dinosaurs, but also the bird-like pterosaurs, large marine reptiles and many smaller land and sea creatures, clearing the way for the emergence of mammals as the dominant life form on the planet. All of this may sound familiar… In recent years, however, some scientists have speculated about alternative causes for the extinction, arguing that it could have resulted from multiple asteroid impacts or, more likely, massive volcanic eruptions at the Deccan Traps in India. To settle the question, European researchers decided to assemble what Kirk R. Johnson of the Denver Museum of Nature and Science called "a K-T boundary dream team," a collection of 45 internationally renowned scientists in a broad spectrum of disciplines to analyze the possible causes of the extinctions.” (Click here for more)
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