When the early Earth formed or about 4 billion years ago, this planet still lacked oxygen.
Reported by Live Science, when the new Earth formed, this planet rotated faster. It then completes its rotation in just 6 hours, but gradually slows down over hundreds of millions of years.
As our planet’s rotation slows, microbes are bathed in longer periods of sunlight, which increases their release of oxygen into the atmosphere.
As the Earth’s rotation slowed, dense layers of cyanobacteria — the first life on Earth — began producing oxygen as a byproduct of photosynthesis.
But scientists still don’t know for sure what triggered the two transformative oxygenation events that transformed Earth from a low-oxygen planet into an oxygen-rich world where complex organisms could evolve and diversify.
But recently, scientists have found clues in sinkholes at the bottom of Lake Huron. Bordering Michigan in the United States and Ontario in Canada, Lake Huron is one of the largest freshwater lakes in the world.
In the depths of the lake live two types of microbes: purple cyanobacteria that seek sunlight, which produce oxygen through photosynthesis, and white bacteria, which consume sulfur and instead release sulphates. Microbes fight for position during the day, with sulphur-eating bacteria blocking the purple microbes’ access to the sun.
However during the day, the white microbes avoid light and leave the purple cyanobacteria exposed and therefore able to photosynthesize and release oxygen.
‘We realized that there is a fundamental relationship between the dynamics of light and oxygen release, and that relationship is based on the physics of molecular diffusion,’ said lead study author Judith Klatt, a researcher at the Max Planck Institute for Marine Microbiology. in Bremen, Germany.
“Shorter days will allow less oxygen to escape from the layers, even if the same amount of oxygen is being produced per hour,” Klatt told Live Science in an email.
This article was published on SINDOnews with the title Scientists find the cause of the oxygen surge so that Earth can be inhabited by humans
Publisher: Dinar Putra