How did life on earth begin?...

[Y]

Lets not convolute the question.....

Did it start by accident?

Did it start by intelligent design?

Did it start by aliens?

Does it make a difference?

One of the major, if not THE major, problem with creationist thinking is that, not only does it not understand the science, it has it arse-backwards.

This is a tough one to not only grasp, but to explain so that others may understand.

Creationist thinking has the specific condition of this planet that supports life as we know it (mankind) being put in place in the beginning by a creator.

The reality is that life developed, and changed, on this planet over time as the conditions of the planet changed.

Which is why we have so many fossils of extinct lifeforms, and if the conditions hadn't changed to favor mammalian hominids and for them to develop a high-order intellect, mankind wouldn't be here to contemplate either a 'creator' or being 'created'.

Which is also why any life found on other orbs in the universe will not necessarily resemble any life found on earth.  The conditions of the other orbs will be different.

Which also means we may have to alter our conception of what constitutes life as we explore the universe.