What is expected if life exists on Mars

Because the starting components and environmental conditions of Mars were similar to those on Earth it is fair to assume that if primitive life forms occurred would have been carbon and water based. With the same starting material as Earth and the work of evolution small, cellular life forms that used complex carbon molecules may have formed. The complexity of the formed life would depend on the speed of evolution. At very least we should expect to find small simple celled colonies having chemolithotrophic metabolisms.