Legend has it that in 1938, a radio broadcast about a Martian invasion of New Jersey incited panic; not everyone realized it was a fictional drama — Orson Welles’ adaptation of The War of the Worlds. Nowadays, people might regard the notion of Martians taking over our planet as pure fantasy. But Steven Benner, a levelheaded scientist of some repute, suggests that perhaps the invasion already occurred billions of years ago. Maybe Martians are not merely among us — maybe they are us.
Benner — a Harvard-trained chemist who started the Foundation for Applied Molecular Evolution, an associated research institute and two bioscience companies — wasn’t trying to be provocative when he presented the idea at a geochemistry conference last August. As a longtime investigator into the origins of life, he’s seen multiple lines of scientific evidence starting to stack up. Microscopic life, he says, might have first taken hold on Mars and then caught a ride on a space rock to our planet, where things evolved from there, so to speak. It’s not as crazy as it sounds.
Overcoming Obstacles
To begin thinking about this, scientists first need to figure out how a genetic molecule capable of jump-starting life might spontaneously arise from a “prebiotic soup” of organic compounds. An obvious candidate, DNA, hides in the cells of every known living organism and is endowed with the ability to encode genetic information and make copies of itself. But many researchers in the primordial biology game, Benner included, focus instead on RNA, or ribonucleic acid, a biological precursor to DNA that can also store genetic information and self-replicate but arises more easily from organic materials.
