Given that life arose so plentifully and easily here on our home planet, and that the ingredients for life are everywhere we look throughout the Universe, it seems like a foregone conclusion that we wouldn’t be alone.
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If that’s the case, why is there only one common ancestor, and one tree of life?
We don’t know that.
Before you say “but Bible!”, be humble enough to accept that what is is, and God told us what we needed to know about it at the time; because we don’t grasp the totality of what is, nor the correct relationship between what is vs what He wrote, none of us know the totality of truth nor is any in a position to condemn another’s understanding thereof.
I also like the statement about the ingredients for life being so plentiful. Would someone mind telling me what the ingredients for life are, because no seems to have an idea what to do with them.