Hmm, I'm not so sure. For two reasons: If we assume that life naturally arises when light is shone at rocks for long enough then we might assume that life on mars would have an independent origin. However, this does not necessarily mean that life there will have orthogonal biochemistry. It may be that the biochemistry we observe on earth is the biochemistry most likely to emerge in a wide range of environments.
On the other side we should consider the possibility that space is porous to life. That life is able to travel between bodies or on bodies that pass through the vacuum of space. In this case we should expect that while there may be independent origins of life, within relatively short distances a certain kind of biochemistry might come to dominate.
Add to this the quite important role that exogenous organic chemicals likely played in the emergence of life on earth, in the case where life arose here and on mars independently. It is probably more likely that life would emerge through roughly the same processes wherever it emerges, therefore in roughly similar environments and using roughly the same building blocks (organic molecules constructed in space and deposited through impacts) we might expect it to have similar forms. I would say that Titan is likely to have something entirely different to earth life - owing to it's very different environment...
On the other side we should consider the possibility that space is porous to life. That life is able to travel between bodies or on bodies that pass through the vacuum of space. In this case we should expect that while there may be independent origins of life, within relatively short distances a certain kind of biochemistry might come to dominate.
Add to this the quite important role that exogenous organic chemicals likely played in the emergence of life on earth, in the case where life arose here and on mars independently. It is probably more likely that life would emerge through roughly the same processes wherever it emerges, therefore in roughly similar environments and using roughly the same building blocks (organic molecules constructed in space and deposited through impacts) we might expect it to have similar forms. I would say that Titan is likely to have something entirely different to earth life - owing to it's very different environment...