For now, life is flourishing on our oxygen-rich planet, but Earth wasn't always that way – and scientists have predicted that ...

Climate change is extending far beyond the threat of melting polar ice caps -- it's putting a dangerous stranglehold on life in oceans, too. A new study published in the science journal Nature ...

For now, complex life flourishes on our planet thanks to its supply of oxygen. But Earth's atmosphere wasn't always like it is today, and scientists predict that in the future, it will revert back to ...

A dangerously low oxygen level—usually below 92%—can cause shortness of breath, confusion, chest pain, or fainting. It’s ...