Scientists rethink why giant insects once ruled the skies, finding oxygen may not explain their size or disappearance.

Three-hundred-million years ago, Earth was very different. The continents had coalesced into Pangea, which was dominated in ...

Scientific consensus is that high oxygen levels allowed these humongous fliers to exist, but a new study throws that idea ...

Learn how ancient oxygen levels in the Paleozoic era were linked to giant insect size, and why that theory is now being ...

Researchers Jeff Crooks and Stephany Garcia checked the minnow traps left at the murky mouth of the Tijuana River on a sunny October morning. They didn’t expect any catches. They haven’t had any for ...

Blood oxygen levels refer to the amount of oxygen circulating in the blood. Normal blood oxygen levels fall between 75 and 100 millimeters of mercury (mm Hg) on arterial blood gas (ABG) test results.

Patients continuously monitored after surgery experienced significantly less time with dangerously low oxygen levels compared ...

SPIRIT LAKE, Iowa (KTIV) - Folks on Big Spirit Lake have been observing strange behavior in the fish there for the past few weeks because of low oxygen levels in the water. While this may sound like ...