The world's biggest bang wiped out the dinosaurs in a cataclysm that swathed our planet in choking dust -- or at least that is what many paleontologists claim. Others say dinosaurs died out gradually as Earth's climate and geology changed.
It sounds a typical academic dispute -- but last week it erupted into open warfare. Allegations have been made of deceit and unethical behavior. One scientist is even alleged to have held back inconvenient evidence.
"This affair has become an object lesson on how partisan and unethical the whole dinosaur controversy has become," said Norman MacLeod, keeper of paleontology at London's Natural History Museum.
"Young scientists are now refusing to get involved in this field because no matter what they say it will offend someone and damage their careers. It's like the nature-nurture debate. No matter what you say, someone will hate you for it."
The furore focuses on a massive drilling project set up to study the Chicxulub crater in Yucatan. Buried under half a mile of rock, the crater was created 65 million years ago when Earth was hit by a meteorite 16km in diameter. The blast would have blotted out the sun for decades, or even centuries, many researchers claim. Given that around this time the dinosaurs became extinct, many scientists made a direct link. Denied sunlight and food, most of the world's animals would have starved, and choked, to death.
But others disagree. Volcanoes, global warming or sea level changes were responsible, they say -- pointing to evidence that most dinosaurs became extinct before the explosion and to the fact that many large animals such as alligators survived this alleged catastrophe. Things weren't that bad, they say.
In a bid to resolve the dispute, a US$3 million project was launched in Yucatan two years ago. Researchers drilled a pipe into the Earth's crust to bring back samples of the meteor and crater wall. By studying what happened just before and just after the meteorite impact, scientists would glean critical insights, it was argued. For example, it would show if all life was extinguished in the millennia that followed the impact.
In 2002 the first samples were brought up. To the disgust of Mexican geologists, and to many scientists who doubted the Big Blast theory, these were entrusted to Jan Smit, a geologist at the Free University of Amsterdam and a leading supporter of the meteorite hypothesis. Promising to cut up the samples and distribute them to project scientists, Smit left with the precious Chicxulub remains. A year later, many scientists were still seeking the promised samples.
"We were dismayed," geochemist Erika Elswick of Indiana University in Bloomington states in the current issue of Nature. "There was no explanation given, no apology."
Eventually some samples were sent out, but most were too small for experiments. Dismay turned to fury. Researcher Gerta Keller, of Princeton University, pressed Smit and at last got a good set of samples. At the European Union of Geosciences conference in Nice, she presented her results, which were a bombshell.
Her research, Keller claimed, clearly showed that marine plankton, far from being killed off by debris blotting out the sun, thrived for hundreds of thousands of years after the crater was created. The meteor that struck at Chicxulub was not responsible for mass extinctions, she concluded.
Nor is Keller reticent in her interpretation of Smit's behavior.
"He tried to postpone our results so that he could remain unchallenged at that meeting," she states in Nature.
Smit dismisses the allegation as "ridiculous." He blames the delays on his busy schedule and poor communications by those running the project. He also claims Keller misidentified some fossils in her samples.
The row is far from over. Project scientists are preparing papers containing results of studies of the samples they obtained from Smit and these will be published in a special issue of Meteoritics and Planetary Science next year. Few doubt it will resolve the issue. As MacLeod says: "It's no longer about science. It's about reputations."
Two former Chilean ministers are among four candidates competing this weekend for the presidential nomination of the left ahead of November elections dominated by rising levels of violent crime. More than 15 million voters are eligible to choose today between former minister of labor Jeannette Jara, former minister of the interior Carolina Toha and two members of parliament, Gonzalo Winter and Jaime Mulet, to represent the left against a resurgent right. The primary is open to members of the parties within Chilean President Gabriel Boric’s ruling left-wing coalition and other voters who are not affiliated with specific parties. A recent poll by the
TENSIONS HIGH: For more than half a year, students have organized protests around the country, while the Serbian presaident said they are part of a foreign plot About 140,000 protesters rallied in Belgrade, the largest turnout over the past few months, as student-led demonstrations mount pressure on the populist government to call early elections. The rally was one of the largest in more than half a year student-led actions, which began in November last year after the roof of a train station collapsed in the northern city of Novi Sad, killing 16 people — a tragedy widely blamed on entrenched corruption. On Saturday, a sea of protesters filled Belgrade’s largest square and poured into several surrounding streets. The independent protest monitor Archive of Public Gatherings estimated the
Irish-language rap group Kneecap on Saturday gave an impassioned performance for tens of thousands of fans at the Glastonbury Festival despite criticism by British politicians and a terror charge for one of the trio. Liam Og O hAnnaidh, who performs under the stage name Mo Chara, has been charged under the UK’s Terrorism Act with supporting a proscribed organization for allegedly waving a Hezbollah flag at a concert in London in November last year. The rapper, who was charged under the anglicized version of his name, Liam O’Hanna, is on unconditional bail before a further court hearing in August. “Glastonbury,
The Vatican Museums on Thursday unveiled the last and most important of the restored Raphael Rooms, the spectacularly frescoed reception rooms of the Apostolic Palace that in some ways rival the Sistine Chapel as the peak of high Renaissance artistry. A decade-long project to clean and restore the largest of the four Raphael Rooms uncovered a novel mural painting technique that Renaissance painter and architect Raphael began, but never completed. He used oil paint directly on the wall, and arranged a grid of nails embedded in the walls to hold in place the resin surface onto which he painted. Vatican Museums officials