Study Provides Compelling Evidence of Single Impact Extinction Theory

ectotherm writes to tell us that a new study at the University of Missouri-Columbia claims to provide compelling evidence that a single meteor impact was the cause of animal extinction 65 million years ago. From the article: "MacLeod and his co-investigators studied sediment recovered from the Demerara Rise in the Atlantic Ocean northeast of South America, about 4,500 km (approximately 2,800 miles) from the impact site on the Yucatan Peninsula. Sites closer to and farther from the impact site have been studied, but few intermediary sites such as this have been explored."

Comments

Re:65 million?

[sRev]

I read this yesterday and have been looking in occasionally to read the comments at the bottom. It looks like there must be some global creationist group that is directing traffic to the story, as every comment makes just that same arguement. I guess the creationist party line is that the "flood" wiped out the dinosaurs. That's a lot of water.

Dating error + meteor frequency = = correlation

[MROD]

The problem with all these sedimentological studies is that the statistical period between large meteorite impacts and the systematic error in the dating of the sediments (using isotopic geochemistry) in addition to the ambiguity in the fossil record (and the dating errors in those sediments) means that it's guaranteed that you will find a correlation between any mass extinction and a large meteorite impact event.

Around the K-T boundery there is not only the Chixalub impact but a large one in Germany and a couple of others which have been discovered, all within the dating error. Add to this that there's also the Decan Traps flood basalts being errupted, ocean currents changing as the north atlantic starts to open and the amount of flooded continental shelf decreasing hugely and you have several possible smoking guns.

The evidence just isn't there currently to say why most of the dinosaur lineages died out (along with many sea reptiles and other oceanic creatures). In fact there is still a doubt as to when it actually happened and over how long a period. Ammonites, it seems, saw the meteorite coming.. about a million years before it hit.