Earth life 'may have come from Mars'

Gale crater, Mars Life would face challenges on Mars today, but billions of years ago conditions might have been better

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Life may have started on Mars before arriving on Earth, a major scientific conference has heard.

New research supports an idea that the Red Planet was a better place to kick-start biology billions of years ago than the early Earth was.

The evidence is based on how the first molecules necessary for life were assembled.

Start Quote

The evidence seems to be building that we are actually all Martians; that life started on Mars and came to Earth on a rock”

End Quote Prof Steven Benner Westheimer Institute for Science and Technology

Details of the theory were outlined by Prof Steven Benner at the Goldschmidt Meeting in Florence, Italy.

Scientists have long wondered how atoms first came together to make up the three crucial molecular components of living organisms: RNA, DNA and proteins.

The molecules that combined to form genetic material are far more complex than the primordial "pre-biotic" soup of organic (carbon-based) chemicals thought to have existed on the Earth more than three billion years ago, and RNA (ribonucleic acid) is thought to have been the first of them to appear.

Simply adding energy such as heat or light to the more basic organic molecules in the "soup" does not generate RNA. Instead, it generates tar.

RNA needs to be coaxed into shape by "templating" atoms at the crystalline surfaces of minerals.

The minerals most effective at templating RNA would have dissolved in the oceans of the early Earth, but would have been more abundant on Mars, according to Prof Benner.

Red or dead

This could suggest that life started on the Red Planet before being transported to Earth on meteorites, argues Prof Benner, of the Westheimer Institute of Science and Technology in Gainesville, US.

Why is Mars so lifeless?

Mars taken by Mars Global Surveyor
  • No magnetic shield: Mars' magnetic field disappeared four billion years ago, allowing the solar wind to strip away the planet's atmosphere
  • The missing atmosphere: Mars has just 1% of Earth's atmospheric pressure, so heat from the Sun escapes into space, making the planet very cold
  • Too cold for liquid water: Mars sits outside the so-called Goldilocks Zone where the temperature is 'just right' for water to remain liquid - vital for life as we know it

The idea that life originated on Mars and was then transported to our planet has been mooted before. But Prof Benner's ideas add another twist to the theory of a Martian origin for the terrestrial biosphere.

Here in Florence, Prof Benner presented results that suggest minerals containing the elements boron and molybdenum are key in assembling atoms into life-forming molecules.

The researcher points out that boron minerals help carbohydrate rings to form from pre-biotic chemicals, and then molybdenum takes that intermediate molecule and rearranges it to form ribose, and hence RNA.

This raises problems for how life began on Earth, since the early Earth is thought to have been unsuitable for the formation of the necessary boron and molybdenum minerals.

It is thought that the boron minerals needed to form RNA from pre-biotic soups were not available on early Earth in sufficient quantity, and the molybdenum minerals were not available in the correct chemical form.

Shergottite meteorite from Mars Meteorites from Mars have been arriving on Earth throughout our planet's history

Prof Benner explained: "It’s only when molybdenum becomes highly oxidised that it is able to influence how early life formed.

"This form of 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."

Early Mars is also thought to have had a drier environment, and this is also crucial to its favourable location for life's origins.

"What’s quite clear is that boron, as an element, is quite scarce in Earth’s crust," Prof Benner told BBC News, “but Mars has been drier than Earth and more oxidising, so if Earth is not suitable for the chemistry, Mars might be.

"The evidence seems to be building that we are actually all Martians; that life started on Mars and came to Earth on a rock," he commented.

"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 may not have been a story to tell."


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  • rate this

    Comment number 120.


    "What is molydenum? How does Professor Benner know that
    "It couldn't have been available on Earth at the time life
    began". How does Professor know that three billion years ago Earth had very little oxygen? And how does Professor Benner know that three billion years ago, Mars did?"

    blah blah etc etc. The prof is "standing on the shoulders of giants"

  • rate this

    Comment number 119.

    That's a very interesting idea and very plausible, more believable then a being called GOD, which if you use your brain and actually think about it, is really NATURE. Religion is on a back slide, and the bible bashers are starting to realise there isn't life after death after all - well there is I suppose - MAGGOTS . Do I believe in a God - No, Do I believe we may be Extra-terrestrial - Yes.

  • rate this

    Comment number 118.

    I can just read all the anti-religious loons choking on their toast from here, responding to the phantom outrage they feel the need to scoff at.

  • rate this

    Comment number 117.

    My gut feel is that is happened on Earth, we just don't know how yet. The origin of life is for me the most fascinating question for science, and one that we seem only to have taken a few faltering steps towards understanding.
    The gigantic leap from a bunch of chemicals to a living thing capable of reproduction is a chasm yet to be solved.
    It all just seems so very "unlikely"..

  • Comment number 116.

    This comment was removed because the moderators found it broke the house rules. Explain.

  • rate this

    Comment number 115.


    Where's Nathaniel when you need him?

  • rate this

    Comment number 114.

    This has no basis at all and is yet another story designed to rubbish our faith.

    The lord almighty created life - re Genesis. We should be thanking the Lord for everything we have. Science has no place in God's creation

  • rate this

    Comment number 113.

    How do we even know if this is mars ?

    It could be all filmed in the arizona or navada desert

    Ask yourself in 1969 did we really land on the moon ?

    With the technological advances we have why has there been no manned space flights to the moon since the 60's ?

    When the moon is so close why can we successfully send a robot to mars which is so far away ?

  • rate this

    Comment number 112.

    May I suggest that we repatriate our glorious Earth leaders back to Mars? They could keep themselves happy fighting over their patches of desert and fulfil their dream of a planet-wide old wild west.

  • rate this

    Comment number 111.

    An interesting article. As an aside, a BBC comments page on a straight forward scientific premise seems a strange place for so many theistically inclined scientists to wrestle with their demons. An objective observer might think this highlights the question of fundamental inconsistencies between faith and science. That and the possibility there are people on here making stuff up of course.

  • rate this

    Comment number 110.

    When we find evidence of life on Mars I think it will be of the same origin as life on Earth.
    There has been plenty of exchange of materials from one planet to another over the history of the solar system that any life we find is likely to have the same source.
    If Mars is the origin then that rock could have been floating in space for tens of millions of years carrying its precious cargo.

  • rate this

    Comment number 109.

    Still guessing I see...

  • rate this

    Comment number 108.


    I can hear all the religious loons choking on their toast from here!

    Science has not proved GOD ALMIGHTY to be a work of fiction, does science mean it can have no proof yet make judgement? Not very scientific really, which i get from most of the haters on here.
    From the gouge on the surface, the ring of dust on saturn, and our moon-we were hit. God started life here.

  • rate this

    Comment number 107.

    So - not the garden of Eden then as I suspect there are no apple orchards on Mars.

  • rate this

    Comment number 106.

    And slowly and surely they drew their plans against us...

  • rate this

    Comment number 105.

    This inevitably leads one to woinder whether life on Mars (if that were the case) came frome somewhere else, and if so from whence?

  • rate this

    Comment number 104.


    @ 57. chickenator88 'the chances of anything coming from Mars was a million to one, they said'

    'Very good, but if you heard more, you'd have heard that still, they come'

    ...and Thunderchild was decommissioned in the defence short-sighted!

  • rate this

    Comment number 103.

    I am afraid I understood little (or nothing) of Professor Steven Benner's remarks. What is molydenum? How does Professor Benner know that
    "It couldn't have been available on Earth at the time life
    began". How does Professor know that three billion years ago Earth had very little oxygen? And how does Professor Benner know that three billion years ago, Mars did?

  • rate this

    Comment number 102.

    re: 60. Philip
    >>>This is a desperate argument from scientists who can't find a logical answer on earth and refuse to accept life was created by God.

    Humans have an innate (and in your scheme of things God-given) need to understand things, So, may it not be that this kind of research is a necessary step along the road to finding your God? There's more than one way to look at it.

  • rate this

    Comment number 101.

    @83. Skye

    Ah, just checked with my source and you're absolutely right, apologies!

    It's agreed, then.


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