Martian

A Martian is an inhabitant of the planet Mars. The term "Martian" was often used jokingly by Humans for aliens, much like "flying saucer" for any alien spacecraft.

Native Martians
At some point during the history of the planet, the Ice Warriors evolved on Mars, (DW: The Ice Warriors) as did many other Martian lifeforms such as Martian fungi. (DW: The Seeds of Death).

The Ice Warriors had developed interplanetary space travel by at least the 1990s and repeatedly tried to invade Earth. (DW: The Ice Warriors, The Seeds of Death, The Dying Days, etc)

Humans as Martians
By the 22nd century, Mars had been colonised by Humans who pushed the native Ice Warriors into poverty. (PDA: Fear Itself)