A Whiff from Blue-Green Algae was Likely Responsible for the Earth's Oxygen
The onset of Earth's surface oxygenation was likely a complex process characterized by multiple whiffs of oxygen until a tipping point was crossed.
The onset of Earth's surface oxygenation was likely a complex process characterized by multiple whiffs of oxygen until a tipping point was crossed.
‘The surface of the Earth was exposed to a low oxygen atmosphere some 0.7-0.8 billion years earlier than previously thought.’
Tweet it Now
The latter is thought to have been the cause for the emergence of animals during the so-called 'Cambrian explosion' nearly 540-520 million years ago. The discovery opens up for the possibility of evolution of the earliest primitive photosynthetic life forms as early as 3.8 billion years ago.
"It is generally believed that early Earth was completely anoxic (without oxygen) but our study shows that the surface of the Earth was exposed to a low oxygen atmosphere already by this time," explained lead researcher Robert Frei from University of Copenhagen.
Modern-day Genomes Help in Understanding Development of Organisms
Modern day genomes have been used by MIT scientists to reconstruct and understand the development of ancient microbes.
Modern day genomes have been used by MIT scientists to reconstruct and understand the development of ancient microbes.
BIFs are marine chemical sediments and retain information on the composition and presence of oxygenation/reduction processes in ambient seawater and on the interaction of the atmosphere with Earth's surface.
Advertisement
Rise in Oxygen Levels Gave Breath of Life to Animal Evolution
It took 100 million years for oxygen levels in the oceans and atmosphere to increase to the level that allowed the explosion of animal life on Earth.
It took 100 million years for oxygen levels in the oceans and atmosphere to increase to the level that allowed the explosion of animal life on Earth.
"This has far reaching implications for how we investigate the pace of evolution of life and its biodiversity on our planet," the authors noted in a paper published in Nature's Scientific Reports.
Advertisement
Ocean Ecosystems may Take Millennia to Recover from Climate-Related Upheavals
As the planet warms, scientists warn that there will be a increase in the number of larger areas with low-oxygen dead zones in the world's oceans.
As the planet warms, scientists warn that there will be a increase in the number of larger areas with low-oxygen dead zones in the world's oceans.
