Question: How did life begin?

Iain Bethune answered on 24 Jun 2015:

Nobody is 100% sure, but all the evidence points to the fact that all life on earth (plants, animals, humans) all evolved from the same source, since the same fundamental structures exist in all life – DNA, cells etc. Whether the first time that life began from all the constituent chemicals on the earth, or elsewhere in the solar system and was perhaps carried to earth by comets is still not known. One of the reasons we go to look for life on other planets like Mars, or Europa (moon of Jupiter) is to see if it’s the same as Earth-life or not, and hopefully find an answer to your question!