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New evidence supports theory that life may have started on Mars

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August 31, 2013

Did life as we know it originate on Mars? (Image: Shutterstock)

Did life as we know it originate on Mars? (Image: Shutterstock)

New evidence presented by Professor Steven Benner at The Westheimer Institute for Science and Technology in Florida suggests that, billions of years ago, Mars was a much better place for the first cells to have formed compared to Earth. This gives more weight to the theory that life may have started on the Red Planet and then found its way to Earth aboard a meteorite.

Life on Earth

The fossil record tells us that life first appeared on our planet around 3.5 billion years ago, but we know very little about how the first cells came to be.

Scientists theorize that, as the Earth slowly cooled down, simple organic compounds (monomers) slowly formed and combined into more complex compounds (polymers). Then, as sea currents pooled these large molecules by "hotspots" like oceanic shores and hydrothermal vents on the sea floor, they may have eventually combined to form the first protocells.

However these building blocks combined, there is growing evidence that the first cells replicated using RNA instead of DNA, and that the switch to DNA replication, which is stabler but harder to achieve, happened only much later in the history of evolution. (One convincing piece of evidence for this is that many of the critical components of cells, which evolve the slowest, are composed mostly or entirely of RNA.)

Inconsistencies

According to Benner, if the RNA hypothesis is true then the story just doesn't add up.

Scientists believe that when life first appeared on Earth our planet was completely submerged in water and very low in dioxygen. Benner says life couldn't have originated under these conditions because borate and molybdate, two crucial catalysts to the formation of RNA, would have been extremely rare.

"If early Earth really was a 'water world,' then borate concentration would have been difficult," Prof. Benner tells Gizmag. "For molybdate, the problem is that it is highly oxidized (four oxygen atoms for every molybdenum atom), and ancient Earth probably did not have much dioxygen in the atmosphere."

When simple organic molecules dissolved in water are given a source of energy but no borate or molybdate are present, the end result is tar, not RNA. Borate minerals help simple organic molecules form carbohydrate rings, and molybdenum then rearranges these rings to form ribose, a crucial building block of RNA. Both these minerals would have been extremely scarce on early Earth, but abundant on Mars.

Life on Mars

Out of the 120 Martian meteorites we have collected so far, some contain promising evidence to support Benner's theory.

"Analysis of a Martian meteorite recently showed that there was boron on Mars," says Benner. "We now believe that the oxidized form of molybdenum was there too. In addition, recent studies show that these conditions suitable for the origin of life may still exist on Mars."

The prospect of extremophile bacteria surviving the trip to Earth inside a meteorite isn't as far-fetched as it may seem.

"We spend much time on 'planetary protection' so that a launch to Mars does not carry Earth bacteria to forward contaminate Mars, but we find that many bacteria (like radiodurans) can survive the trip, especially if tucked inside of the craft (or, by analogy, within the meteorite)," Benner says.

While there is no "smoking gun," the evidence presented by Prof. Benner gives more credibility to the theory that life may have first started on Mars rather than Earth. It also gives us more hope of finding life back on the Red Planet, and perhaps even elsewhere in the solar system.

Source: Goldschmidt via BBC

About the Author
Dario Borghino Dario studied software engineering at the Polytechnic University of Turin. When he isn't writing for Gizmag he is usually traveling the world on a whim, working on an AI-guided automated trading system, or chasing his dream to become the next European thumbwrestling champion.   All articles by Dario Borghino
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11 Comments

Far from "smoking gun", the alleged evidence consists entirely of a theoretical problem with the (theoretical) formation of life on Earth. But, it's a BIG planet and life only needs one spot to get itself going. The 'Mars origin' theory still has zero evidence to support it.

piperTom
1st September, 2013 @ 06:09 am PDT

I have to agree with piperTom... it sounds far fetched and even if conditions were difficult and rare, these conditions were not impossible and therefor may have been enough. It's a pity that I think its only a matter of time before we accidentaly contaminate Mars, and i would be seriosuly surprised if we haven't already.... actually, if we haven't already contaminated Mars, it kind of weakens the theory of how some life can survive the trip.. especially given that the landers had a comparitavley soft friendly ride compared to the proposed explosive launch from mars, the trip through space along with all the cosmic radiation, then the violent reentry and horrific planetry impact... wow... i know we 'steralise' everything.. but seriously, you can't keep out every spore time after time through every step.

SciFi9000
1st September, 2013 @ 07:24 pm PDT

I like my theory that all binary stars are nursing mothers and once the infant leaves the nursery orbit to occupy the first orbit it would force all other occupants to do the same. Pauli's Exclusion Principle perhaps.

That means when Mercury left mummy's side everything that was on the surface of Mars was left in that orbit while the naked Mars was flung to where he is now, cold and angry. Broad breasted Gaia jumped in and scooped up all the RNA etc just the same as Mars did after Jupiter vacated.

So therefore we could all be Jupits. Maybe that's our problem, we are all a bit jupit.

Sounds feasible to me.

bernardpalmer
1st September, 2013 @ 09:01 pm PDT

This theory limits human life to a extremely small chances of any type of life as we know it in the universe. Think of the odds of a small or large meteorite blowing off of Mars and finding another planet like ours, landing on it and then starting.. life. What do you think the odds are 1 in 100 to the power of infinity. In other words, none. So, with that in mind are we alone?

S Michael
1st September, 2013 @ 10:20 pm PDT

"Analysis of a Martian meteorite recently showed that there was boron on Mars," says Benner. "We now believe that the oxidized form of molybdenum was there too. In addition, recent studies show that these conditions suitable for the origin of life may still exist on Mars."

My question is, do they believe that the oxidized form of molybdenum was present just so that it fits their model of life originating on Mars?

Stating "we believe" without supporting evidence is about as unscientific a statement as you can make.

Rt1583
2nd September, 2013 @ 01:21 am PDT

What if only the Borate, etc, on those meteorites came trough, and crashed where it could make a difference, on Earth?

Wouldn't that facilitate life beginning, but still here on, Earth?

Edgar Castelo
2nd September, 2013 @ 02:59 am PDT

It does seem "stretched" and it does look like the universe is "playing pool"...however:

The universe is vast and that's considering the small part of it that we have knowledge of... and we still have found no other life forms (at least officially...not trying to fire up x-files fan club here)... so that means, so far, we (life on earth with a species that has considerable intelligence...or at least with some specimens that have some...can't really go global here) are the most illogical, improbable, happening in the universe.

So with all that in mind can we be arrogant enough to rule out a theory immediately because it seems "stretched"?

That is dis-considering the fact that we are in fact primitive and limited in knowledge of how the universe truly is and works, and dis-considering the fact that the "string theory" could be true, and dis-considering the fact that we could be limited in analysis by our own dimensional limitation.

It could happen... a big pool game where the rock we now call moon scratches mars and then looses the momentum on it's final earth rubbing, being laid to rest at the orbit of it, but leaving bacteria proliferating in a ocean that looked more like a nutrient soup than actual water...and probably with a less aggressive protective atmosphere still being formed.

It could be as simple as a contamination! E.T. went to Mars on vacation, stepped on a couple of bacteria, then on its way home decided to drop by at earth for a quick swim... or just for photos... or maybe to collect samples...or maybe to experiment, dropping some mars rocks on to it's oceans...or they just crashed.

Maybe this is something done by someone/thing from another dimension... the example from Carl Sagan explaining the shock that a 2 dimensional being (the sheet of paper) would have when a 3rd dimensional being grabs his friend (the sheet of paper nr 2) from point A and places it in point B is something that comes to mind. In the example, Carl Sagan (the 3 dimensional being) grabs sheet of paper nr 1 and drops it 20 cms apart from where it was. In the eyes of the 3d being this seems simple grab and drop, but the 2d being sheet of paper nr 2, his friend just disappeared and magically re-appeared 20cm apart! I mean... every 2d sheet of paper being he reports his happening to will think this is "stretched".

My point is... a lot could happen that could help explain this "crazy" theory....and the worse thing is that there are probably even more weird ways of explaining it that we don't even know of, and we may still be years/ages away from having that knowledge.

Anyway, judging by the princess of mars from John Carter, I honestly am ALL in favor of the theory...that's some quality DNA folks ;) Just hope the asteroid rubbed her instead of the green guys with 4 arms!!!

manuel.jose.ribeiro
2nd September, 2013 @ 03:56 am PDT

The theory 'The mathematics of evolution' shows that every planet of our ´Solar System´ is a isolated system with its proper life. So Mars had its destiny and after was the time to Earth, It is possible that Venus will be the next to have life. In each system (planet) things will be something different. May be in the next future we can learn something from Mars (that comes first of ours) to direct our life to the correct way.

Hélio Barnabé Caramuru
2nd September, 2013 @ 06:44 am PDT

"Evidence" is proof so why is it still called a theory?

donwine
2nd September, 2013 @ 10:26 am PDT

@donwine

There are a lot of misconceptions about what "theory" is in a scientific context. In common usage, theory is used like "guess" but inScience it has a much deeper meaning.

Example:

We witness things fall to the ground if we drop them. That's a fact because it's a publicly observable, repeatable phenomenon. We hypothesize that mass attracts other mass. We test it by looking for evidence and we discover that it does.

The hypothesis is then published in a scientific journal and other scientists try to prove it's wrong by a process known as "falsification". If no one can falsify it, then eventually it will become a theory, the highest form of proof available outside of mathematics.

In that sense a scientific theory is practically a fact.

Occasionally problems are discovered in theories. Newton almost got it right with his "laws" of motion but Einstein showed he was wrong at speeds approaching the speed of light. So even laws are subject to refinement but it's rare.

If you treat "theory" as "fact" you will seldom get it wrong.

warren52nz
2nd September, 2013 @ 04:27 pm PDT

Thanks warren52nz. That will help me a great deal. The next time I need a large home loan I will theorize that I am wealthy and get a huge salary every week.

Conjecture and blind credulity have no place when it comes to having a sound mind. Even faith is based on enough facts to place ones hope.

donwine
3rd September, 2013 @ 04:44 am PDT
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