You ducked my question. Does the theory of evolution make the claim that we all evolved from a common ancestor? Yes or No.Does evolution not claim there is a common ancestor? In order for the theory to be given credibility you first have to address the origin of life. .But we don't need to know how life started on earth- to see that Evolution(in the most overreaching and basic sense of the term) is the reason for the variety of life here on Earth- and for much of the reason of the distribution of life on earth.
Nope- actually the theory has amazing credibility and never once describes how life began.
Whether life somehow came into being on Earth, whether microbes from other planets 'seeded' earth, or whether some sky fairie planted microbes on earth- all immaterial to the theory of evolution.
As I said before- I don't need to know where the water came from, when I look at a river, to know that the river is flowing past me.
As always- this is your straw man to divert attention away from the topic of evolution.
So now- as asked before- what is the theory that you believe accounts for life on earth as we know it?