Saturday, September 27, 2003
Astronotes: The inside scoop on the Universe at large.
Astronotes: The inside scoop on the Universe at large.: "Controversy Erupts over Dinosaur Death-by-Asteroid Theory
Since 1990 when solid evidence for an impact crater was found at Mexico's Yucatan Penninsula, scientists have all but decreed that the event 65 million years ago did the dinosaurs in.
But there have always been doubters.
Now one has stepped forward in a manner others have been reluctant to. Princeton paleontologist Gerta Keller said this week that the demise of dinosaurs was long and slow, and that volcanic activity and general climate change were primary factors. "
The question here is: How long did it take dinosaurs to die? If it's within the course of less than 100 years, then it makes Gerta's theory look rather pale. Then you'd have to find some way of discounting any effect by the asteroid (that ties in with the age of the crater and the world-wide layer of asteroidal metal that was laid down at the same time as the asteroid).
Personally, when I think of the effects of anything big enough to make a 125-mile-wide dent in the planet, that is still 9,000+ feet deep, I have to wonder why ANYTHING survived it, much less large animals like dinosaurs. I guess there were scattered protected pockets around the globe, wheer life survived. The overall effect, though, had to be severely traumatic to any living thing on the planet.
It's a shame we can't gather enough data to tell anything significant about the Big Rock and the way it struck the planet. I say that because there were apparently other die-offs during the past. The difference is that something about this one was so abrupt and so total that the previous lanlords of Earth never made it back to supremacy. If someone came to me and said "Well, the earlier die-offs and extinctions weren't final because they were gradual and allowed dinosaurs to repopulate.", I'd be willing to take that as a possibility. But when someone comes to me and says "They died because of gradual cliamtic changes.", I have to put that a lot lower on the list.
Based on the evidence to date, the dinosaurs went out all over the planet and VERY quickly. That spells 'sudden change', to me.
Like an asteroid impact.
Since 1990 when solid evidence for an impact crater was found at Mexico's Yucatan Penninsula, scientists have all but decreed that the event 65 million years ago did the dinosaurs in.
But there have always been doubters.
Now one has stepped forward in a manner others have been reluctant to. Princeton paleontologist Gerta Keller said this week that the demise of dinosaurs was long and slow, and that volcanic activity and general climate change were primary factors. "
The question here is: How long did it take dinosaurs to die? If it's within the course of less than 100 years, then it makes Gerta's theory look rather pale. Then you'd have to find some way of discounting any effect by the asteroid (that ties in with the age of the crater and the world-wide layer of asteroidal metal that was laid down at the same time as the asteroid).
Personally, when I think of the effects of anything big enough to make a 125-mile-wide dent in the planet, that is still 9,000+ feet deep, I have to wonder why ANYTHING survived it, much less large animals like dinosaurs. I guess there were scattered protected pockets around the globe, wheer life survived. The overall effect, though, had to be severely traumatic to any living thing on the planet.
It's a shame we can't gather enough data to tell anything significant about the Big Rock and the way it struck the planet. I say that because there were apparently other die-offs during the past. The difference is that something about this one was so abrupt and so total that the previous lanlords of Earth never made it back to supremacy. If someone came to me and said "Well, the earlier die-offs and extinctions weren't final because they were gradual and allowed dinosaurs to repopulate.", I'd be willing to take that as a possibility. But when someone comes to me and says "They died because of gradual cliamtic changes.", I have to put that a lot lower on the list.
Based on the evidence to date, the dinosaurs went out all over the planet and VERY quickly. That spells 'sudden change', to me.
Like an asteroid impact.
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