Dramatic drops in oceanic oxygen, which cause mass extinctions of sea life, come to a natural end - but it takes about a million years.
A low level of atmospheric oxygen in Earth's middle ages held back evolution for 2 billion years, raising fresh questions about the origins of life on this planet.
For the development of animals, nothing—with the exception of DNA—may be more important than oxygen in the atmosphere.
The evolution of the first land plants including mosses may explain a long-standing mystery of how Earth's atmosphere became enriched with oxygen, according to an international study led by the University of Exeter.
A couple of times in four billion years, evolution has slowed to a crawl. And an eon or so has passed before more complex life forms, such as simple animals, could arise.
As climatologists closely monitor the impact of human activity on the world's oceans, researchers at the Georgia Institute of Technology have found yet another worrying trend impacting the health of the Pacific Ocean.
Research published this week by an international team of scientists, including the British Antarctic Survey, provides new insights into how carbon dioxide changed in the oceans surrounding Antarctica during glacial periods.
Falling oxygen levels caused by global warming could be a greater threat to the survival of life on planet Earth than flooding, according to researchers from the University of Leicester.