Thanks to science fiction writers, Hollywood studios, and TV sitcoms, many species of Martians have wandered into our space here on Earth. If we can take them as representative of what occupies their planet, we can assume that Martians can be aggressive, prone to identity crises, single-minded, and simple-minded. Certain Martian-inspired images are the stuff of nightmares; others come with a built-in laugh track. If evidence of life on Mars ever surfaces, it will never hold up to what our imaginations have already created.
Pictured above: Invaders From Mars, 1953. Martians turn Earthlings into zombies.
The War of the Worlds
Herbert George Wells' 1898 story, The War of the Worlds, introduced three-legged "fighting-machines."