-
( 5BYA)
The solar system was a swirling mass of dust and gas. The Sun began to form, also. -
(4.6 BYA)
The earth began to form. It was a hot ball of carbon dioxide, water vapor and nitrogen. -
(4 BYA)
Volcanos were created and began to form the atmosphere. -
(4 BYA)
Cells similar to archaea were populating the earth at this point -
(3.5BYA)
Fossils of stromatolites were found that date back to this point. -
(3 BYA)
Some forms of life had become photosynthetic, which means they used the sun for food and energy. -
(2.2 BYA)
Earth appeared similiar to how it does today. -
(2 BYA)
O2 levels reached today’s levels. -
(1.5 BYA)
A type of small aerobic prokaryote was engulfed by another prokaryotic cell and together they lived and reproduce to form eukaryotic cells. -
(1 BYA)
Ozone (O3) formed which protected organisms from harmful UV rays so they could exist on land and develop more. -
(Between 1600 -1700)
Scientists concluded that life did not come from a non- living force in the air. Redi’s experiment- contributed to this when he placed meat in 2 jars to observe where life came from. -
(Between 1700-1800)
Spallanzani’s experiment was when he boiled broth and left one opened and the other seeled to see if life formed from the broth. This was similiar to Redi’s experiment.
The first Microscopes were important because scientist were able to use the microscopes to see the microorganisms. -
(Between 1900- present)
Thomas Cech found that a type of RNA found in some unicellular eukaryotes is able to act as a chemical catalyst, similar to the way enzymes act. Used the term ribozyme.
Oparin’s hypothesised about where the orgins of simple compounds came from.
Urey and Miller tested Oparin’s hypothesis about where the simple compounds came from, which did explain and support the hypothesis.
This led to our understanding of were life came from. -
(Between 1800-1900)
Pasteur’s experiment was when he made a curved kneck flask to showed even though top was open, the broth wasn’t growing life. -
(Between 1900- present cont.)
Lynn Margulis proposed that early prokaryotic cells may have developed a mutually beneficial relationship.
Fox did extensive research on the physical structures that may have given rise to the first cells.
Radiometric dating determining the age of an item by comparing the relative percentages of a radioactive isotope and a stable isotope.
All of this contributed to the knowledge we have now about the earth.
