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(5 BYA) Solar System
Around 5 billion years ago, our solar system began to shape itself from a swirl of dust and gases. With that, the sun began to form. -
(4.6 BYA) Earth
Earth began to form from colliding with space debris.
Radiometric dating was used to decipher the date of many of the objects found in this time period and other early ones. -
(4 BYA) Rocks and Crystals
Collisions between Earth and large pieces of space debris ended at this time, and as a result the Earth's surface cooled enough for the oldest known rocks and crystal to begin to take shape. In addition, organic molecules may have begun to accumulate. Microspheres, or nucleotides or amino acids, were the first examples of this. -
(3.5 BYA) First Fossils
Cyanobacteria began to form stromatolites on Earth's surface which became the first fossils ever found. -
(3 BYA) Photosynthetic Life
At this time in Earth's history, some forms of life became photosynthetic (originally photosynthetic cyanobacteria). -
(2.2 BYA) A Happy Earth
A large point in time occurred now, when Earth's conditions settled to become what they are today because of cooling. -
(2 BYA) Oxygen and Ozone
O2 reached today's levels. Ozone was also beginning to form because of sunlight hitting the oxygen. -
(1.5 BYA) Endosymbiosis
Aerobic prokaryote began to live and reproduce inside larger anaerobic prokaryote also known as endosymbiosis. -
(1 BYA) Ozone Layer
Oxygen that was produced by photosynthetsis created the ozone (O3) which, when formed, protected organisms from harmful UV rays so they could exist on land -
(1600) Redi's Experiment
Tested whether or not rotting meat that was kept away from flies would produce more flies on its own. The result of this experiment was that no flies grew from the meat. -
(1700) Spallanzi's Experiment
Spallanzi experimented with a sealed flask and an open flask, and the effects they had on broth. The result was that the closed flask kept the broth clearer for a much longer period of time. -
(1600) Microscopes
The microscope was invented by Robert Hooke which was then used worldwide to study the “vital force” -
(1800) Pasteur's Experiment
Pasteur’s experiments used a variation of Spallanzani’s design to support that microorganisms are carried in the air and to disprove "vital force". -
(1900) Urey and Miller
Tested conditions of organic synthesis or chemosynthesis with the Miller-Urey apparatus. -
(1900) Fox's Research
Researched the physical structures of cells. -
(1900) Oparin's Hypothesis
Oparin’s hypothesis (concerning what the early atmosphere was composed of) was important in 1953 when Stanley Miller and Harold Urey conducted an experiment to test the hypothesis. -
(1900) Thomas Cech
In the early 1980s, found that a type of RNA found in some eukaryotes was capable of acting as a chemical catalyst called ribozyme. -
(1900) Marguilis's Findings
Margulis hypothesized that the cells chloroplasts probably came about when a host organism ingested phosynthetic bacteria. Margulis found that bacteria and organelles show many similarities.
