Scientists Claim First Life on Earth May Happen in Underwater
- space.com
That's because Earth's early atmosphere lacked free oxygen, and therefore no ozone layer to protect it from the sun's harmful ultraviolet radiation.
Instead, life would be sheltered underground or deep in the oceans, where it would be shielded from damaging ultraviolet rays.
Rhodopsin actually began to evolve into its more modern form about 2 to 2.5 billion years ago, when Earth's atmosphere was suddenly flooded with oxygen produced by microscopic photosynthetic cyanobacteria in the so-called Great Oxidation Event.
It’s also known as the Oxygen Disaster because changes in the atmosphere resulted in the extinction of a large number of microbial species that did not breathe oxygen.
Furthermore, this flood of oxygen immediately creates an ozone layer that counteracts the sun's harmful ultraviolet radiation allowing microbes that can adapt to the new oxygen-rich conditions to leave the oceans and subterranean recesses, spreading more freely across the earth's surface.
Also, with more wavelengths of sunlight on offer than deep in the oceans, rhodopsin evolved to absorb it too.
"The Early Earth was an alien environment compared to our world today, understanding how organisms here have changed over time and in different environments will teach us important things about how to find and recognize life elsewhere." Schwieterman said.Â
Melonjak 69 Persen, MSIG Life Bukukan Laba Bersih Rp 181 Miliar di Semester I-2026
PT MSIG Life Insurance Indonesia Tbk (MSIG Life) membukukan laba bersih sebesar Rp 181 miliar di semester I-2026, atau meningkat signifikan mencapai 69 persen secara yoy.
