Latest Timothy Lyons Stories
UC Riverside-led research team finds evidence for a dramatic rise in early oxygen about 2.3 billion years ago followed, more surprisingly, by an equally impressive fall Most researchers imagine the initial oxygenation of the ocean and atmosphere to have been something like a staircase, but with steps only going up. The first step, so the story goes, occurred around 2.4 billion years ago, and this, the so-called Great Oxidation Event, has obvious implications for the origins and evolution...
Discovery challenges previous models for environment in which early life evolved Over the last half-billion years, the ocean mostly has been full of oxygen and teeming with animal life. But earlier, before animals evolved, oxygen was harder to come by. Now a new study, led by researchers at the University of California, Riverside (UCR), reveals that the ancient deep ocean was not only devoid of oxygen but also rich in iron, a key biological nutrient for nearly a billion years...
New findings from UC Riverside-led team alter traditional ideas about ancient ocean chemistryGeologists at the University of California, Riverside have found chemical evidence in 2.6-billion-year-old rocks that indicates that Earth's ancient oceans were oxygen-free and, surprisingly, contained abundant hydrogen sulfide in some areas."We are the first to show that ample hydrogen sulfide in the ocean was possible this early in Earth's history," said Timothy Lyons, a professor of...
A spike in ancient marine phosphorus concentrations from 750 to 635 million years ago is linked to emergence of complex life, UC Riverside researchers sayA team of scientists, led by biogeochemists at the University of California, Riverside, has found new evidence linking "Snowball Earth" glacial events to the rise of early animals.The controversial Snowball Earth hypothesis posits that the Earth was covered from pole to pole by a thick sheet of ice lasting, on several occasions,...
Stratified marine basin sheds new light on early animal evolution, UC Riverside scientists sayA research team led by biogeochemists at the University of California, Riverside has developed a detailed and dynamic three-dimensional model of Earth's early ocean chemistry that can significantly advance our understanding of how early animal life evolved on the planet.Working on rock samples from the Doushantuo Formation of South China, one of the oldest fossil beds and long viewed by...
Even low concentrations of oxygen can have profound effects on ocean chemistryScientists widely accept that around 2.4 billion years ago, the Earth's atmosphere underwent a dramatic change when oxygen levels rose sharply.Called the "Great Oxidation Event" (GOE), the oxygen spike marks an important milestone in Earth's history, the transformation from an oxygen-poor atmosphere to an oxygen-rich one, paving the way for complex life to develop.Two questions that remain unresolved in...
A UC Riverside-led study reports on the effects of biological oxygen production nearly 100 million years before oxygen accumulated in the atmosphereScientists widely accept that around 2.4 billion years ago, the Earth's atmosphere underwent a dramatic change when oxygen levels rose sharply. Called the "Great Oxidation Event" (GOE), the oxygen spike marks an important milestone in Earth's history, the transformation from an oxygen-poor atmosphere to an oxygen-rich one paving the way...
UC Riverside-led study tracked biogeochemical signatures preserved in ancient sedimentary rocks to establish nature and timing of oxygenation of Earth's atmosphereA deficiency of oxygen and the heavy metal molybdenum in the ancient deep ocean may have delayed the evolution of animal life on Earth by nearly two billion years, a study led by UC Riverside biogeochemists has found. The researchers arrived at their result by tracking molybdenum in black shales, which are a kind of sedimentary rock...
