Friday Headlines: 2-1-13

Friday Headlines, February 1, 2013

THE LATEST IN THE GEOSCIENCES

TAPEWORM EGGS DISCOVERED IN 270 MILLION YEAR OLD FOSSIL SHARK FECES

Do I really need to say more? It’s an intestinal parasite…

…in fossil shark poop.

Ew.

Two related headlines here:

STUDY REBUTS HYPOTHESIS THAT COMET ATTACKS ENDED 9,000-YEAR-OLD CLOVIS CULTURE

PREHISTORIC HUMANS NOT WIPED OUT BY COMET, SAY RESEARCHERS

Comet, asteroid, and meteor impacts have been blamed for several of the Earth’s greatest extinctions, including the one at the Cretaceous-Tertiary (K-T) Boundary that led to the extinction of the dinosaurs (and later dominance of mammals). It’s only natural then, when an extinction is identified in Earth’s history, to take a moment and look for evidence of an impact.

The Clovis culture disappeared from North America about 9,000 years ago. That’s similar to when many of North America’s ‘megafauna,’ or giant animals, went extinct, like the woolly mammoth and giant ground sloth. For the extinction of the megafauna, most arguments hinge around human over-hunting or climate change, because that was about the same time that humans made it onto North America and it was also the end of the last glaciation.

There are some, however, who argue that an impact event caused the extinction of the megafauna and then also the demise of the Clovis culture. There was even a Nova documentary about it. Alas, the newest and best evidence soundly rebuts this idea. There are no impact craters from that time period (though it’s been argues that the comet hit the ice cap). There’s no shocked minerals either. Minerals take on the appearance of being disrupted (or shocked) due to the force of impacts. Shocked quartz is common from the K-T boundary event, but there is none associated with this 9,000 year old event. No impact occurred.

The downside is that we still don’t know what happened to the Clovis people.