Word: kellers
(lookup in dictionary)
(lookup stats)
Dates: during 2000-2009
Sort By: most recent first
(reverse)
...Spee Club, and freshmen entry-ways, took part in the event’s climbing competitions. Winners of the matches were given outdoors-themed prizes. Sporting goods companies including Eastern Mountain Sports, Patagonia, la Sportiva, and Five Ten donated $1,500 in prizes for the event, organizers said. Keller C. Rinaudo ’09, who raised 45,000 dollars for the creation of the Lowell wall and organized its construction during the summer of 2006, said he wanted to create a social scene at Harvard that doesn’t revolve around drinking. According to Rinaudo, the climbing wall...
...what role would volcanoes have had to play in all this? A big one, argues Gerta Keller, a Princeton University paleontologist, who recently made her case at a meeting of the Geological Society of America. Geologists have known for centuries that a swath of central India was buried by a series of eruptions at around the time of the dinosaurs' demise. The remains of the flows, known as the Deccan Traps, still cover some 193,000 sq. mi. (500,000 sq km). The eruptions would have poured carbon dioxide and sulfur dioxide into the air, triggering runaway global warming...
...Keller believes she has evidence that they were, thanks to microscopic fossils of foraminifera, a type of plankton that largely died with the dinosaurs. Precisely dating the dinosaurs' demise is tough because most bones disintegrate before they can be fossilized. Plankton, by contrast, are preserved in ocean sediments. Keller studied sediments near the impact site in Mexico, where a massive bloom of new plankton species should have emerged within a handful of millenniums after the impact, taking advantage of the evolutionary room the extinctions created in the ocean. She found her bloom, all right, but 300,000 years later than...
...Keller's scenario, the Deccan eruptions began perhaps half a million years before the mass extinction. "This leads to greenhouse warming that puts a major stress on the environment," she says. Then came the asteroid impact, which pushed things further toward catastrophe. Finally, 300,000 years later, the eruptions reached their climax, sealing the dinosaurs' fate. "We've shown convincingly," she says, "the mass extinction came about 300,000 years after the asteroid impact...
...Keller may be convinced, but others aren't. Sediment samples off the coasts of Senegal, Florida and Antarctica contradict her timeline, suggesting the mass extinction came right after the asteroid impact. "We've got beautiful sediments," says Brian Huber, a curator of paleontology at the Smithsonian Institution. "We have a continuous record of the event." Even 65 million years after the crime, the identity of the real perp is once again in dispute. And with eyewitnesses out of the question, the debate could go on for a while. India 65 million years ago and today...