The growing scientific interest in the "virus first hypothesis" (VFH) as an early step in the origin of life has practical implications for searches and life detection on future Mars missions. The suite of life-detection methods on future missions could miss important biosignatures because instrument designs currently follow a biased definition of life. There is growing support for the possibility that viruses represent the oldest branch of life on Earth and are precursors of microbial cells. Therefore, future and already existing concepts for Mars sample return missions should be coordinated across disciplines to include hypotheses of virologists and evolutionary ecologists. In addition to ensuring a broader search for life on Mars, it may be the only potential way to falsify competing hypotheses of evolutionary virology.