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(5 BYA) Solar System Development
Around 5 Billion Years Ago, the solar system was but a swirling mass of gas and dust. It was forming together as gravity pulled material together to create the sun. After many repeated collisions of debris, the planets were formed. With all these small steps, the solar system slowly started to piece itself together. -
(4.6 BYA) Collisions
About 4.6 billion years ago, plantets were forming because of repreting collisions of debris. In addition to these collisions, other collisions caused the Earth's surface to be reshaped. Thermal Energy also had an effect on the reshaping of the Earth's surface. -
(3.5 BYA) Stromatolites
3.5 Billion years ago, stromatolites were in existance. This is known because there are fossils of these stromatolites today. Growing in colonies, these stromatolites form lynbgya. Because of the fossils, we are able to have a better idea of what was occuring 3.5 billion years ago. -
(4 BYA cont) Age of the Earth
Thanks to radioactive dating, scientist are able to prove the age of materials. It provides a lot of information of aging of fossils and evolution. Radioactive dating is very accurate, so it is sure to be true! -
(4 BYA) Age of the Earth
The estimated age of the earth is abut 4 billion years ago, which is 700,000x as long as the period of recorded history! The oldest known rocks and crystals are from about 4 billion years old, therefore, it's inferred that organic molecules began to accumulate about 4 billion years ago. The oldest unmelted surface rock was the key indicator telling when the earth's surface actually began to form. Because of this, scientist know that the age of the earth is around 4 billion years. -
Mid 1800s
Louis Pasteur conducted an experiment to clear up the controversy over spontaneous generation. He recreated Spallanzani’s experiment, but instead of sealing the flask, he curved the neck of it to prevent microorganisms from contaminating it. -
(1650's) developmental forms of flies.
Francesco Redi discovered that flied come from eggs that other flies laid by conducting an experiment. This experiment proved that flies are not generated spontaneously from rotting meat and that flies come from other flies laying eggs. -
(1650's) Microscopes
Scientists began using microscopes to observe tiny microorganisms. These observations releaved that the world has many tiny creatures. Investigators concluded that microorganisms arise spontaneously from a vital force in air. -
1900s
Sidney Fox and other scientists have done extensive research on the structures theat may have given rise to the first cells. -
Spallanzani
Lazzaro Spallanzani conducted an experiment to observe how and when microorganisms would effect the broth. -
1920s
Alexander I. Oparin and John B.S. Haldane proposed that the early atmosphere contained ammonia, hydrogen gas, water vapor, and compounds made of hydrogen and carbon.
Oparin hypothesised that the reactions of gases forming simple organic compounds and water vapor forming lakes and seas ultimately would have resulted in macromolecules essential to life.
