Tuesday, July 08, 2008

Seeding the Universe - or at Least Earth

I intended to post this some time ago, but I've been too busy. Maybe most everyone has heard about it, but for those who haven't, it is interesting. A couple of months ago, several scientists reported that they found proto-DNA in a meteorite that collided with the Earth back in the 1960s. What this does is lend some support to the panspermia theory - that life on Earth came from someplace other than Earth.

Most scientists are not willing to go as far as stating "life came from outer space," but a few are suggesting that meteorites such as this one might have provided life on Earth with an evolutionary advantage.

The researchers did indeed check the meteorite to see if it was contaminated by material from Earth, and according to their findings, it was not. This rock came with its own proto-DNA. Members of the research time are quoted everywhere, and now here:

Lead author Dr Zita Martins, of the Department of Earth Science and Engineering at Imperial College London, says that the research may provide another piece of evidence explaining the evolution of early life. She says:

“We believe early life may have adopted nucleobases from meteoritic fragments for use in genetic coding which enabled them to pass on their successful features to subsequent generations.”

Between 3.8 to 4.5 billion years ago large numbers of rocks similar to the Murchison meteorite rained down on Earth at the time when primitive life was forming. The heavy bombardment would have dropped large amounts of meteorite material to the surface on planets like Earth and Mars.

Of course the panspermia theory isn't new either. Speculation that life on Earth might have come from Mars, Europa, Titan, or other remote regions have existed for years. Fans of science fiction are likely thinking this is old news, and in that genre it is. In any case, it is certainly exciting to think about.

5 comments:

Charles Gramlich said...

I guess I'm not quite sure what they mean by Proto DNA. Pretty much my understanding is that RNA is proto DNA. I guess we also have to assume, although I imagine they can test it, that the meteorite is not one that was originally blasted OFF earth.

Jeff Edwards said...

I don't have Horrors Beyond 2 in front of me right now, so the words might not be quite right, but: "The double strand function is complete."

-Jeff

Stewart Sternberg said...

I live for this stuff. Not that it will change my life much, but this information affirms my belief that there is something out there. Me and Fox.

John Stanley said...

I want to believe...

William Jones said...

Charles - There are a few articles on the topic, and each has varying details. In general, what I've found is that the molecules xanthine and uracial were present on the meteorite, and those are the building blocks (or some) for DNA.

Put that way it does sound less dramatic, doesn't it? :)

Jeff - Ha! Yes, my tale, "When the Stars Fell," in HB2 is premised on this concept - without saying as much. The line you quoted does sum that up.

Stewart - Have you heard about the "white stuff" discovered on Mars?

I don't that it influences my life, unless we can now catch "space colds," or worse. :)

John - I do to. I think the scientists working on the project did as well, which is why they have to make sure their data was accurate. Surprisingly, this didn't seem to play much in the news. Or maybe that isn't surprising.