Mars....a future earth?

ok so this is my take on things.
even with all of the scientists and everyone who knows everything about the climates of planets and such...
Is mars a future earth?
noone really knows what is capable of happening to our climate or atmosphere...
Because there is some concrete (well not proof) but some evidence(whether you want to say that or not) that there was/is/are life forms and structures on mars.
could this be what is to come?
did beings survive on mars?
or am i just stupid?
any ideas?