A team of Australian scientists believes to have found out the missing details about how the first animals appeared on Earth and evolved, eventually leading the way towards humans.
Researchers have been looking for that missing link which kick-started life. For around three billion years, life on the planet is believed to have remained at a single-cell phase. During these times, bacteria must have dominated in this watery world.
Algae Blooms, the Link We Were Looking For?
Some 650 million years ago, “the snowball Earth” is considered to have started melting. This caused the frozen equatorial oceans to turn back into water. According to this new study paper, this also led to an ‘explosion’ of algae blooms.
“Huge glaciers ground entire mountain ranges to powder that released nutrients, and when the snow melted during an extreme global heating event, rivers washed torrents of nutrients into the ocean,” stated Jochen Brocks.
He is the study’s lead author and an Australian National University Professor. The study states that the much larger algae started feeding on the nutrients released from the mountainsides and glaciers by the melting.
Then, this explosion of algae blooms started replacing the microscopic bacteria that had until then dominated the planet. According to the team, this change led to “a revolution of ecosystems”.
Namely, it probably caused a change at the base of the food system. One that then made possible the existence of humans.
The study team states to have found definite proof of this change in ancient sedimentary rock samples. Ones that were extracted from the central Australian desert.
The team crushed the rocks until they turned to powder and then extracted ancient organisms’ molecules from them. In doing so, they noted a drastic shift in the number of extracted molecules. They found a 1,000-fold rise in the value of molecules indicative of complex organisms.
Study findings and details were released and are available in the journal Nature.
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