All life on Earth

Those earlier forms of life that were not well adapted died. We are descended from the organisms that did well.Organisms that evolve on a quite different world will doubtless sing its praises too.All life on Earth is closely related. We have a common organic chemistry and a common evolutionary heritage. As a result, our biologists are profoundly limited. They study only a single kind of biology, one lonely theme in the music of life. Is this faint and reedy tune the only voice for thousands of light-years? Or is there a kind of cosmic fugue,with themes and counterpoints, dissonances and harmonies, a billion different voices playing the life music of the Galaxy?