What was the first form of life on life on earth?

Answer 1

The first life forms were essentially arrangements of atoms that had the ability to arrange other atoms exactly like themselves. Eventually, more complex organisms evolved due to mutations in the copying sequence that were beneficial to the organism. These organisms were more efficient at accomplishing this task of reproduction. Stromatolites are the first form of life to photosynthesize and produce breathable oxygen in vast quantities, and reanimating the atmosphere with oxygen. They are also the oldest form of life visible w/o a microscope. These Stromatolites would secrete cya-no bacteria in thin layers, and year after year they would build upon one another. Stromatolites can be dated back over 3.5 billion years ago. Before that (some 3.8 billion years ago life) after a period known as the late heavy bombardment, life known as extremofiles thrived in toxic pools of amino acids and acidic water, where the PH levels were harsh enough to digest a battery. Although Earth 3.8-4 billion years ago had very little to no oxygen in its atmosphere and temperatures were well over what we consider to be habitable, these rare and minimally researched life forms still managed to survive these unbearable conditions. Microbial life itself dominated the planet Earth for over 3.6 billion years and we may owe our very lives to there unchanging and determined path for existence.

Answer 2

sharks?