No Moon, no life on Earth, suggests theory

NewScientist.com ^ | 18 March, 2004

[Leroy S. Mort]

Without the Moon, there would have been no life on Earth.

Four billion years ago, when life began, the Moon orbited much closer to us than it does now, causing massive tides to ebb and flow every few hours. These tides caused dramatic fluctuations in salinity around coastlines which could have driven the evolution of early DNA-like biomolecules.

This hypothesis, which is the work of Richard Lathe, a molecular biologist at Pieta Research in Edinburgh, UK, also suggests that life could not have begun on Mars.

According to one theory for the origin of life, self-replicating molecules such as DNA or RNA emerged when small precursor molecules in the primordial "soup" polymerised into long strands. These strands served as templates for more precursor molecules to attach along the templates, creating double-stranded polymers similar to DNA.

But the whole theory fails without some way of breaking apart the double strands to keep the process going, says Lathe. It would take some external force to dissociate the two strands, he says.

Doubling up

As an analogy, he points to PCR, the technique used to amplify DNA in the lab. DNA is cycled between two temperatures in the presence of appropriate enzymes.

At the lower temperature of about 50 ýC, single DNA strands act as templates for synthesising complementary strands. At the higher temperature of about 100 ýC, the double strands break apart, doubling the number of molecules. Lower the temperature, and the synthesis starts again. Using this process, a single DNA molecule can be converted into a trillion identical copies in just 40 cycles.

Lathe believes that thanks to the Moon, something similar happened during Earth's early years. Most researchers agree that the Moon formed five billion years ago from debris blasted off Earth in a giant impact.

A billion years later when life is thought to have arisen, the Moon was still much closer to us than it is now. That, plus the Earth's much more rapid rotation, led to tidal cycles every two to six hours, with tides extending several hundred kilometres inland, says Lathe. Coastal areas therefore saw dramatic cyclical changes in salinity, and Lathe believes this led to repeated association and dissociation of double-stranded molecules similar to DNA.

When the massive tides rolled in, the salt concentration was very low. Double-stranded DNA breaks apart under such conditions because electrically charged phosphate groups on each strand repel each other.

But when the tides went out, precursor molecules and precipitated salt would have been present in high concentrations. This would have encouraged double-stranded molecules to form, since high salt concentrations neutralise DNA's phosphate charges, allowing strands to stick together.

Unrelenting cycles

These unrelenting saline cycles would have amplified molecules such as DNA in a process similar to PCR, says Lathe. "The tidal force is absolutely important, because it provides the energy for association and dissociation [of polymers]."

Many researchers do not believe DNA and RNA were the first replicating molecules. Graham Cairns-Smith of the University of Glasgow, UK, thinks much simpler "genetic" material formed first, from the crystallisation of clay minerals.

But he says Lathe's idea deserves attention. "Whatever the replicating entities were that started the evolutionary process, it would be significant that they lived in an environment in which the conditions were changing."

If the theory is right, life could not have evolved on Mars, says Lathe. Phobos, the larger of Mars's two Moons, is so small that the tidal forces it generates are just one per cent of those generated by our Moon. "Even if there was water on Mars, life could not have evolved there because these polymers could not have replicated," he says.

[K1avg]

Wow, it's bad enough that they try to force this spontaneous generation garbage down our throats, but now they argue that the moon is responsible for life?

Sheesh...

[LiteKeeper]

The DNA carries information that is used like a blueprint to build proteins out of amino acids. Where did that "information" come from? Information is never self-generated, nor can "matter" generate information. So all that DNA needs a source for it's information. Any ideas where it comes from?

[BenLurkin]

When the moon hits your eye like a big-a pizza pie
That's amore
When the world seems to shine like you've had too much wine
That's amore

Bells'll ring ting-a-ling-a-ling, ting-a-ling-a-ling
And you'll sing "Vita bella"
Hearts'll play tippi-tippi-tay, tippi-tippi-tay
Like a gay tarantella

When the stars make you drool joost-a like pasta fazool
That's amore
When you dance down the street with a cloud at your feet, you're in love
When you walk in a dream but you know you're not dreamin', signore
'scusa me, but you see, back in old Napoli, that's amore

(When the moon hits your eye like a big-a pizza pie, that's amore)
That's amore
(When the world seems to shine like you've had too much wine, that's amore)
That's amore

Bells will ring

ting-a-ling-a-ling

ting-a-ling-a-ling

And you'll sing "Vita bella"

Vita bell-vita bella

Hearts will play

tippi-tippi-tay, tippi-tippi-tay

Like a gay tarantella

Lucky fella

When the stars make you drool just like pasta fazool
That's amore (that's amore)
When you dance down the street with a cloud at your feet, you're in love
When you walk in a dream but you know you're not dreaming, signore
'scusa me, but you see, back in old Napoli, that's amore

Amore
That's amore

[Fiddlstix]

Ping

[Diogenesis]

polyAAAAA reproduces itself.
All life has DNA which begins with polyAAAAA.
The DNA which was best covered and protected, then did the best.

[Ken522]

Without the Moon, there would have been no life on Earth.

Wait - this might be the secret justification for worshipping the moon after all!

[orionblamblam]

> spontaneous generation garbage...

Wait. Where were Creationists mentioned int he article? They're the only ones yapping about "spontaneous generation garbage" as part of their biogenesis "theory..."

[BikerNYC]

Any ideas where it comes from?

I don't know, but if it comes from somewhere, I am really curious as to how that "somewhere" got it.

[djf]

Correct. I think early environments needed to be "contained" in some sense. The best way to desribe it is that early life probably resembled, more than anything else, something that had the consistency of egg whites. Having a thicker type medium prevents the whole mess from being diluted and washed out into the open oceans.

I have written an essay on the subject that a few have read, I remember being stunned by the findings of Thermus Aquaticus and TAQ polymerase.

The development of the cell wall, well, that's another whole problem entirely...

[LiteKeeper]

Perhaps the Eternal God had "it" all along, and when He created life, He made that part of the package. Methodological naturalism [read, "evolution"] can not come up with any better explanation. Abiogenesis is impossible...and that has been demonstrated over and over again.

[BikerNYC]

But I thought you said it had to come from somewhere. Your violating your own premise by saying that at some point it did not have to come from somewhere...that it was always there.

I don't see how your theory solves any problems.

[fella]

Looks more and more like the Earth is the only place where the Lord has placed life. And He told us to go forth and multiply .... Out there.

[djf]

And God said, "Let the waters bring forth abundantly the moving creature that hath life..." Gen 1:20

[staytrue]

The cell wall is mostly a glob of fat or oil that forms a bubble in water. A lot of fats will do this spontaneously.

[GeronL]

My GUANO detector is hitting the higher frequencies with this story. Pure BS

[pepsionice]

One curious thing...which I don't think anyone caught...is that the moon used to be a lot closer billions of years ago...so does this mean that it is slowly creeping away from the earth...even today?

[socal_parrot]

Actually, they were talking about Christopher Cross' musical careear. After all, without the moon, what else would you be stuck between with New York City.

Best that you can do is fall in love...

[orionblamblam]

> does this mean that it is slowly creeping away

Yes, it is, at a rate of centimeters per year, IIRC. This has been repeatedly measured using lasers and the reflectors left by the Apollo astronauts.

What is happening is that tidal forces are in play. The total angular momentum of the Earth-Moon system is remaining essentially constant, but the system, via tidal drag, is exchanging the Earth's rotation for the moons revolution. Basically, the day AND month are getting longer. As memory serves, in some billions of years both will be approximately twice what they are now. And then the sun will go FOOM, and the issue becomes moot.

[farmer18th]

These tides caused dramatic fluctuations in salinity around coastlines which could have driven the evolution of early DNA-like biomolecules.

could

what speculative drivel. Does someone get paid to write this nonsense?