Little Green Men or Just Little Microscopic Organisms? The question of life on Mars is a puzzle that has plagued many minds throughout the world. Life on Mars, though, is a reality. When you think of Martians, you think of little green men who are planning to invade Earth and destroy all human life, right? Well, some do and some do not. Though believing that there are little green men on Mars is just a fantasy, or is it? The kind of life that may have lived there is the kind you would never consider of giving the name "Martian" to. They are small organisms such as microbes or bacteria. Proof of this