You are saying that you have never heard an atheists say he believes in abiogenesis?
No, I'm saying I don't think I've ever heard an atheist claim that evolution answers how life began. That's abiogensis, not evolution.
and/or that you do not think atheists lump abiogenesis with evolution?
Right...I've never heard one that did.
What theories on the origins of life do you think most atheists believe?
Natural ones since we currently see no evidence for supernatural beings to instigate a supernatural origin. I was posting this in response to another post, but it fits here so I'll drop it here.
One explanation posits a natural explanation for a phenomenon. We know natural explanations are factual for millions of other things we see around us...suggesting a natural explanation thus falls in line with what we know to be true in countless other examples. The other explanation posits a supernatural explanation which on its face remains untestable. Other than similar untestable claims, we have no evidence that the supernatural is the explanation for any phenomenon we see anywhere.
Put another way, even if you dislike the theory of evolution, suggesting a supernatural explanation is a nonstarter until you establish the existence of the supernatural. And even if you were to be able to do that, all you would gain is the ability to suggest ANY and ALL supernatural explanations, not any one in particular.