It's hard to see how life debris in an entropic universe could really do anything useful (except for hugely exciting our imaginations if we ever found it), considering the light years of travel between suitably benign environments and the harsh realities of eons spent in space which would seem to be inimical to delicate organic molecules. It would be nice to have the evidence but much too fanciful an idea that it could seed life all over again. I've never bought into that notion, though who knows. From Mars, maybe, just about... On the other hand, it's a good bet that the conditions under which life may have originated on earth (which I tend to think was the case) are replicated billions of times over in the universe. Now I do like that idea. I also wouldn't mind betting that life elsewhere would almost certainly be carbon-based and dependent on liquid water, and would be subject to some form of evolution by natural selection. It's worked so well on Planet Earth that, well, can you really think of a better plan?