Research the dark timeline where every path led deeper into the interstellar medium
3 billions years ago on Planet Earth the atmosphere was low in oxygen, dominated by gases like methane (CH₄),
carbon dioxide (CO₂), nitrogen (N₂), and water vapor (H₂O). Oxygen was almost nonexistent—less than 1% of today’s levels.
The skies might have appeared reddish or orange due to the scattering of sunlight by methane and other gases.
Life was dominated by single-celled organisms like bacteria and archaea, thriving in the oceans.
These were some of the earliest forms of life on Earth. Around this time, cyanobacteria (photosynthetic microorganisms,
also called blue-green algae) began to flourish. They used sunlight to produce energy and released oxygen as a byproduct—a process
that would eventually transform Earth’s atmosphere. Oxygen produced by cyanobacteria was quickly absorbed by iron in the oceans,
forming vast deposits of iron oxides (banded iron formations) on the seafloor.
for another billion years Free oxygen in the atmosphere would not accumulate significantly, during the Great Oxidation Event.
So there were no plants, animals, or fungi yet.
Complex, multicellular life was still over a billion years away. The landscape was barren, as life had not yet colonized land.
Continents, if present, were relatively small, rocky, and devoid of vegetation.
This era was a time of slow but critical transformations.
TZ conducte research on Isolani Allele’s studies in tardigrades