[joseph20]

"Moreover, the earth has been around for some 4.5 billion years and the first traces of life have already been found at some 3.5 billion years ago. This is just what we have discovered: it's quite possible that life existed on earth even earlier. What this means is that, within the scope of evolutionary time, life appeared on earth very quickly after the earth itself was formed."

Not so. Life could have come to Earth from elsewhere in the universe, either by accident or by intention.

By accident, life could have evolved over billions of years elsewhere in the universe, and then landed on Earth via a meteor or comet or some other natural delivery.

By intention, life on Earth could have been brought here by an intelligent species of aliens.

The article's assumption that life must have come into being on Earth is flawed. Therefore, the argument that there was such a short period of time for life to form by natural causes, and that therefore it's improbable that life formed by natural causes, is also flawed.

[Crush T Velour]

By accident, life could have evolved over billions of years elsewhere in the universe, and then landed on Earth via a meteor or comet or some other natural delivery.

Actually, it is worse than that.

Evolutionary Biology states that ALL life on Earth evolved from a single ancestor. This is argued for very compelling reasons. Yet, even though Earth is self-evidently hospitable to Life, and even though trillions of wet, protein-filled bags of lifeforms offer more environments for unique Life to originally occur, it has only happened once in 3.5 billion years (roughly one quarter the age of the Universe). Moving Life's origin to another planet does not solve the problem of its incidence here.

[nuf said]

"Life could have come to Earth from elsewhere in the universe, either by accident or by intention."

Are you sure you want this to be your argument? Dont forget the necessity for life building material that result from supernova. I hope I dont have to explain the ramifications of this. Ok, hint. Age of universe `13 bil.