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(5 BYA) The start of the Universe
Five billion years ago the solar system began to form. -
(4.6 Billion Years ago) Formation of Earth
The Earth began to form and grow larger as gravity kept pulling debris in, and some of the thermal energy created from these collisions was able to melt Earth's surface. It is predicted that 4.6 billion years ago the moon was created due to a collision with an astroid that sent chunks of Earth into the orbit of the Earth. -
(4 BYA) Crystal, Rock Formations and Radioactive dating
With the use of radiometric dating the oldest known crystals and rock formations are known to be around 4 billion years old. Radiometric dating is a method of establishing the age of materials which uses an atoms difference in its number of neutrons or isotopes. -
(4 BYA) Organic Molecules Formation
Organic molecules began to accumulate around 4 billion years ago. The organic compounds could have been created when the many gases from the Volcanoes of Earth and other places began to react with each other due to the very high temperatures of the time. -
(3.5 BYA) Bacteria begin to Form
Fossils of cells similar to modern cyanobacteria, in the form of stromatolites are found to be around 3.5 billion years old. Bacteria may have begin to form due to the molecules and compounds accumulation in lakes and seas when the Earth began to cool which eventually led to the creation of the Bacateria. -
(3BYA) Photosynthetic Life appears
Some forms of life are beginning to become photosynthetic. An explanation of early evolution is found in the theory of Endosymbiosis in which could explain the appereance of photosynthetic organisms. -
(2.2 BYA) The Earth begins to appear as it does today
Through the process of erosion and tectonic plates the Earth begins to appear as it does today. This will begin to place different environments on earth and thus new organisms will be created in order to adapt with the changes while old orgaisms will die off if not able to adapt. -
(2 BYA) Oxygen levels reach todays level
O2 levels reached today’s levels. Through the numerous chemicals reations taking place on Earth oxygen reaches the level it is at today which will again cause some organisms to adapt. -
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(2-1.5 BYA) Mitochondria is created
The theory of endosymbiosis consisting of a small aerobic prokaryote being engulfed by and live inside a larger anaerobic prokaryote which eventually led to/evolved in the modern mitochondria. The evolution of the mitochondria would allow more complex organisms to be created eventually. -
(1.5 BYA) Mitochondria Appears
The theory of endosymbiosis consisting of a small aerobic prokaryote being engulfed by and live inside a larger anaerobic prokaryote which eventually led to/evolved in the modern mitochondria. The evolution of the mitochondria would allow more complex organisms to be created eventually. -
(1 BYA) Ozone is Formed
The Ozone(O3) layer is formed around the Earth protecting potential land organisms from harmful UV rays. The formation of the Ozone layer will allow for land organisms to begin to develop without the threat of harmful UV rays and other exsisting small organisms to adapt to the lack of UV rays. -
(1627-1692 A.D) Reidi's Experiment
Redi’s experiment- Francesco Redi (1626-1697) noticed the different developmental forms of flies that eventually led him to question the common belief that flies spontaneously generate from rotting meat. In his experiment he covered a jar with meat inside and left another open with meat inside as well. Maggots began to appear in the open jars but not in closed jars which showed that flies come only from eggs lain by other flies. -
(1665 A.D) Creation of Microscope
The Microscope is created by two dutch eye glass makers but is officially used by Robert Hook when he notices "pores" in a cork. The creation of the miscroscope would eventually lead to other revelations in the understanding of biology. -
(1729-1799 A.D) Spallanzini's Experiment
With the creation of the microscope Spallanzini is able to see microorganisms. Spallazini does not believe in the common belief of a vital force so he designs an experiment to prove his case involving meat broth. Spallanzini is right but his theory is still not accepted. -
(1822-1895 A.D) Louis Pasteur's experiment.
Louis Pasteur would set up an experiment that would prove the principles of biogenesis and cause others to give up their belief in spontaneous generation. -
(1920 A.D) Oparin's Hypothesis
Alexander I. Oparin came with a theory that the early atmosphere contains ammonia, hydrogen gas, water vapor, and compounds made of hydrogen and carbon such as methane. Oparin’s hypothesis was that these gases at high temperatures might have formed simple organic compounds such as amino acids, and these organic compounds would collects in lakes and seas when the Earth began to cool eventually entering complex chemical reactions which would then lead to macromolecules which are essential to life. -
(1953) Urey and Miller's Experiment
Harold C. Urey and Stanley L. Miller did set up an experiment using Oparin’s hypothesis as a base for the experiment. Their experiment consisted chamber that contained the gasses mentioned in experiment. This experiment and other variations that followed were able to produce amino acids as hypothesized along with a variety of other organic compounds. -
(1912-1998) Sidney Fox's Research and Experiments
Sidney Fox did extensive research on the physical structures that may have led to the creation of the firsts cells. Structures include microspheres and coarcervates which formed spontaneously in the laboratory from solutions of simple organic chemicals -
(1980 A.D)
Thomas Cech was able to find that a type of RNA found in some unicellular eukaryotes were able to act as a chemical catalyst. These finding supports the hypothesis that life could have began with self-replicating molecules of RNA. This hypothesis could provide which molecule or cells would eventually lead to the creation of more complex organisms. -
(1938-? A.D) Lynn Margulis's Endosymbiosis Hypothesis
Lynn Margulis provided a hypothesis or though on how the eukaryotic cells may have evolved in which they may have developed a mutually beneficial relationship with the prokaryotic cells. The theory eventually became the endosymbiosis in which the eukaryotes provide a beneficial environment and the prokaryotes provide a method of energy synthesis.
