Origin of life on Earth

Origin of life on earth
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Origin of life on earth
Scientists have debated the origin of life on planet Earth, and there are competing theories for this. To further explain the origin of life, scientists have done experiments to prove their theories, but there is no single theory that is acceptable to all. Nonetheless, all the theories agree that it is though propagation that living things continue to live on planet Earth. Even though, scientific theories are fairly recent there were hypotheses explaining life’s origin from ancient philosophers. Additionally, scientists posit that all living organisms had a common ancestor, as represented by shared characteristics among living things distributed among the various living kingdoms. This paper will look into three theories on the origin of life, the extraterrestrial explanation, and origin as heterotrophs and as autotrophs.
The theory of extraterrestrial origin of life states that life could probably have started outside planet Earth, whereby spores or seeds from outer space were deposited on Earth. The are various explanations to this phenomenon, with some scientists also stating that life was always there on planet Earth, and hence there is no need to look for explanations on the origin of life. Nonetheless, movement of spores from different planetary spaces to Earth offers the most plausible explanation for the extraterrestrial origin of life (Enger et al., 2007). The various explanations for movement of spores are not in agreement, there are various mechanisms through which this takes place and this could have been from meteorites, comets or other heavenly bodies, from which the spores came into the earth from outer space.
The heterotroph hypothesis posits that life star...