If there is life on Mars then where did they go? Underground? If so why? Well if you look at mars you can see it is near a barren waste land with little water(Ice is water)and some evidence of vegitation. (yes) Now by looking at rocks you can tell there was water and alot of it. If there was water then most definetly there was plant life and maybe humaniods. Most likly there was and there still is. But where are they? They could be underground waiting out for there planet to recover. Recover? From what you might be saying now. Here is some answers witch are very logical. War,mass use of natral resources(like humans), and destruction of atomostsphere(kinda like humans) War is a very likly idea. Why? Look at us we have WMD's (Weapons of mass destruction) like the atom bomb mustard gas and many more out there so if the Martians had a WW then it could have gone into a DEFCON1 sitution and fired some nukes at each other if this is what happened it could explain the massive craters. I dont think i will have to support my other ideas they are kinda self-explanatory if you do not think so look at the human race. The only other idea that i can think of is a natral destruction like a metorite. Now i know this is gonna come up as a question in the future if there was intelligent life then where are the cities? They have decomposed or were obilterated in what ever happend because this could have happend way before we were even walking.
These are my ideas and they are logical

MER WILL REIGN AND YOU SHALL BOW