User blog comment:Spark321939/Are aliens good or will we be advanced enough?/@comment-1217267-20130429203217/@comment-160529-20130430171331

ah, but realize this. If there is an ecosystem or form of life that operates under a sufficiently different biochemistry (or alternative to biochemistry) than an earth-based ecosystem might be sufficiently different that the two will not harm each other!

Take for example theoretical rock-like lifeforms, they may not be harmed at all by hte presence of earthly creatures, and ismply go about their business doing what they do.