Ichthyosaurs swam the seas at the same time as dinosaurs roamed the Earth and pterosaurs reigned the skies, but they may have died out before their land- and air-dwelling brethren, Stinnesbeck said. A global depletion of oxygen in the oceans, possibly due to volcanism, may have caused the extinction of these seagoing reptiles, he said.
The discovery of these creatures establishes the Chilean glacier as one of the prime sites for Early Cretaceous marine reptiles worldwide, the researchers said. But getting to the fossil site is half the battle. To reach it, the team had to drive for five hours, hike for 10 to 12 hours to camp and then hike another two hours, sometimes in heavy rain, hail or snow.
"This has been one of the toughest field camps I ever had," Stinnesbeck said.
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