I remember hearing something relatively recently about how they detected some complex molecules with one of the rovers (indicative of life creating them), but t

I remember hearing something relatively recently about how they detected some complex molecules with one of the rovers (indicative of life creating them), but the leading theory was that they were leftover from when the rover was being built and weren't cleaned enough. So that's definitely a possibility, we aren't looking at a slide and seeing them move, we're just looking for some chemicals so dead bacteria trips the sensors just as well as live.