The existence of extraterrestrial life or proto-life organic evolution in isolated environment of Mars is question of ontological magnitude.
Mars is probably the only place in solar system where some living forms may exists. The extraterrestrial environments are protected by Outer Space Treaty. All NASA spacecraft sent to other planets must undergo meticulous procedures to make sure they don't carry biological contamination from Earth to their destinations.
affirms that the search for extraterrestrial life is an important objective of space research, that the planet of Mars may offer the only feasible opportunity to conduct this search during the foreseeable future, that contamination of this planet would make such a search far more difficult and possibly even prevent for all time an unequivocal result, that all practical steps should be taken to ensure that Mars be not biologically contaminated until such time as this search can have been satisfactorily carried out, and that cooperation in proper scheduling of experiments and use of adequate spacecraft sterilization techniques is required on the part of all deep space probe launching authorities to avoid such contamination
May massive human presence avoid massive contamination?