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How do we exist?
Question Date: 2018-03-12
Answer 1:

Interesting question Ethan. Since I am an evolutionary biologist I will give you an answer from my perspective.

About 4.5 billion years ago the earth formed at a particularly important distance from the sun; enough heat, but not too hot. Over another billion years, the atmosphere of the earth changed dramatically and then incredibly (and lucky for us) life came to be and started to evolve. The first life forms weren't much to look at, just molecules in a prehistoric ocean that were able to make copies of themselves. Some molecules were better at making copies of themselves than others and over a long long long time this competition led to the formation of more complex life forms. Eventually a life form made its way onto land.

About 500 million years ago the first animals with backbones emerged (vertebrates) from which we are descended. Humans have been in existence for about 200,000 years; that's a tiny fraction of how long the earth has been around.

Our position in the universe and the beautiful process of evolution is how we exist.



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