The evidence "seems to be building that we are actually all Martians" and "that life started on Mars and came to Earth on a rock," according to a scientist from The Westheimer Institute for Science and Technology in the US.
Professor Steven Benner said, "It's lucky that we ended up here nevertheless, as certainly Earth has been the better of the two planets for sustaining life. If our hypothetical Martian ancestors had remained on Mars, there might not have been a story to tell."
Prof Benner told the Goldschmidt 2013 conference in Italy that the oxidised mineral form of the element molybdenum, "couldn't have been available on Earth at the time life first began, because three billion years ago the surface of the Earth had very little oxygen, but Mars did".
"It's yet another piece of evidence which makes it more likely life came to Earth on a Martian meteorite, rather than starting on this planet," he added.