Evolution: it works, bixbites

By Phil Plait | November 13, 2008 5:00 pm

Sometimes, a news item comes out that makes me slap my forehead and say, why didn’t I think of that!

In this case, it’s about evolution… kinda. Scientists at the Carnegie Institution of Washington’s Geophysical Laboratory have studied the different processes that change the types of minerals present on Earth over time. What they found is that, overwhelmingly, the biggest process that has changed the mineral abundances over time is… life!

Yeah, us. But it makes such obvious sense. Life takes in various substances, processes them, and then, um, excretes out a different substance. And it’s not just us lumbering apes eating, drinking, and pooping. Plants do it, birds do it, bees do it. Bacteria really dominate the planet, and are responsible for all sorts of chemical changes to the minerals on Earth.

Life isn’t the only thing going on, of course. In the beginning (if I may use that phrase), the Universe was pretty simple. A few minutes after the Big Bang the entire chemical composition of normal matter consisted of hydrogen, helium, and a taste of lithium. It wasn’t for a few hundred million more years that stars formed, and started crunching these elements in their cores, converting them through nuclear fusion into carbon, nitrogen, oxygen, and more. When these stars went supernova a short time later, the explosive forces crafted the elements into even heavier ones, like iron, calcium, nickel, and so on.

Eventually, simple minerals formed. These coalesced in gas clouds into more stars, orbited by planets. That’s when other forces got to work: chemical changes, weathering, various pressures and temperatures transmogrifying one mineral into another.

But when life formed, that’s when things got serious. It changed our entire planetary atmosphere, creating free oxygen, a highly active chemical. It changed the oceans, the land. Everything.

This new study confirms this idea (you can see scientist Robert Hazen talking about all this here). They found that the mineral composition of Earth has changed along with life; as life changed, so did the chemical content of our planet. And, of course, as the mineral content of the Earth changed, so did life. And almost no place has been untouched; incredibly, they found that two-thirds of the 4000 known minerals on Earth can be linked to biological activity.

Like I said, this seems so obvious, but this study makes it very clear and quantifies it. It makes a strong connection between two different fields of science, which is always cool. It means we have a new way of looking at things, a new way of thinking about things, a new way to study things.

And it shows one of the overwhelming strengths of science: it shows that science is not a pile of facts. It’s a growing, almost living series of ideas, and that it’s self-consistent. One field of science is connected to every other field, and they all hang together. In a very real sense, science is a tapestry, a woven and interconnected series of ideas… just like the Universe itself is.

And that’s no surprise to me at all. Science is the Universe; it’s our way of investigating it, observing it, and understanding it. Science is a way to get ever closer to truth.

And it works.

CATEGORIZED UNDER: Cool stuff, Piece of mind, Science
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Comments (35)

Links to this Post

  1. links for 2008-11-14 | Yostivanich.com | November 14, 2008
  2. Evolution of minerals « Mixotricha | November 17, 2008
  1. Clayton
  2. LibraryGuy

    Yay..1st! But why? Is everyone still talkin’ about the Enterprise?

  3. LibraryGuy

    Alas! Not fast enough!

  4. zpmorgan

    I’m going to outlaw evilution and all of its evidence.

  5. Awww, Phil, I’m disappointed. I’m glad there’s a study confirming it, but it’s been pretty obvious to us geology types for decades. Here’s another bit of trivia that’ll blow you away, if you don’t already know it… Where is most of the carbon on Venus? In the atmosphere. Where is most of the carbon on Earth? In the rocks. We generally think of oil, coal, etc, but in fact organic or “fixed” carbon is a tiny fraction of a percent of total C; most is tied up as carbonate, CO3 with a minus 2 charge. Now here’s the kicker… if you could release all that carbonate as carbon dioxide, how would the atmosphere change? Well, it would increase the pressure by a hundred-fold. Our atmosphere would be, in bulk, almost identical to Venus’. Haven’t run the numbers on sulfur/sulfate, but I suspect you’d get similar results. There are two features of Earth that allow carbon dioxide to become mineralized as carbonate… water and life.

  6. Got a link to the actual paper?

  7. This connection is exactly why the “history of evolution” class at my university was in the Geology department.

  8. Scott D.

    See: http://en.wikipedia.org/wiki/Banded_iron_formation

    This is probably one of the best and simplest examples of life having an impact on “large-scale” geology. Photosynthetic life oxygenated the oceans, which caused dissolved iron in our primordial oceans to oxidize and settle out as layers of iron rich deposits. We don’t see these kind of iron deposits before a certain period, which just so happens to coincide with what we believe is a time of proliferating photosynthetic life.

    Yeah, you could call it coincidence, but there certainly isn’t a better explanation for why these formations suddenly start appearing 2 billion years ago.

  9. Hey, Phil Plait, and everybody else, check out this interactive web-site: Evolution — What Next?

    N.B. Shockwave™ player required.

  10. The Gaia hypothesis proponents will run with this one, big time!
    You might want to alert PZ to this… Does he read the BA Blog? I wonder where he stands on the Gaia Hypothesis (or theory as some suggest)…

    It is a cool bit of science, though, either way…
    Rich

  11. IVAN3MAN
  12. Brian

    I was fortunate enough to go to a lecture by Dr. Hazen on this topic just this past Monday at GMU. I have followed his work and books for a few years now, and he is truly a great speaker. Got my book (Origins) signed and everything! woot!

  13. José

    Sometimes, a news item comes out that makes me slap my forehead and say, why didn’t I think of that!

    That’s exactly how I feel every time I see one of those fancy horseless carriages roll by.

  14. gopher65

    I’ve been saying for years that our planet got grey gooed… well, green gooed… a long time ago. Self-replicating simple molecules covered the planet in grey (green) slime. They ate all the good minerals for fuel, and left the garbage behind.

    It’s kind of creepy to think that we’re the result of the grey (green) gooing of a planet. Even naturally occurring grey goo is creepy.

  15. Naomi

    Very Saganish post *grin* Which reminds me! I was checking the Amazon page for Death from the Skies!, and saw this –

    ‘ Frequently Bought Together
    Death from the Skies!: These Are the Ways the World Will End . . . + Bad Astronomy: Misconceptions and Misuses Revealed, from Astrology to the Moon Landing + The Demon-Haunted World: Science as a Candle in the Dark
    Total List Price: $57.85
    Price For All Three: $38.83

    * This item: Death from the Skies!: These Are the Ways the World Will End . . . by Ph.D., Philip Plait
    * Bad Astronomy: Misconceptions and Misuses Revealed, from Astrology to the Moon Landing “Hoax” by Philip C. Plait
    * The Demon-Haunted World: Science as a Candle in the Dark by Carl Sagan ‘

    Thought you’d get a kick out of your books being sold with the amazing Demon-Haunted World :) I know I would!

  16. IBY

    Yeah, it is cool the way all of the iron we use for materials comes from iron ores oxidized by living things when oxygen was saturating the atmosphere around 2 billions of years ago.

  17. “Hey, Phil Plait, and everybody else, check out this interactive web-site: Evolution — What Next?

    N.B. Shockwave™ player required.”

    That is AWESOME!

    However, more than a Shockwave player is required. Also, a high-resolution screen format (and eye assistance, depending on age/condition) is required, in order to see it all properly. :

  18. !AstralProjectile

    Sure life can change rocks from sendimentary to igneous (I’m thinking H-bombs) BUT THEY ARE STILL ROCKS!!

  19. redx

    Even educated fleas do it. :)

  20. gruebait

    In the far future, should there be geologists among some intelligent species, I’m sure they will note that, about 65 my after the KT boundry with its iridium marker, there will be a stratum marked by whatever plastic turns into. Wonder what they’ll call it.

  21. Cheyenne

    Oh man! I tried out this line last night “baby, you and me could make so much heat we could totally transmogrify one mineral into another”. And it worked! All we got was Yttrium though. So I don’t think we’re a good match.

    If I find somebody that can transmogrify tin to vanadium though- I’m totally into that.

  22. I had the same reaction to that article, Phil. It was one of those times when I was made to think about the world a little differently.

    Not being a geologist, like some here, apparently, the findings were novel to me too.

  23. Donnie B.

    Isn’t this just a wee bit anthropocentric… no, wait, make that vivicentric?

    After all, the geologic changes due to life are limited to a relatively thin layer of the Earth’s crust. It just so happens it’s the layer we live on top of. Still, I doubt that life has had much effect on the core or mantle, which make up the overwhelming bulk of the Earth.

  24. Todd W.

    @Donnie B

    I could imagine that the subsuming of plates, pushing upper-crust material down into the mantle, could result in life having an indirect effect on that layer.

  25. José

    @Donnie B.
    After all, the geologic changes due to life are limited to a relatively thin layer of the Earth’s crust.

    I guess you’ve never heard of the three “M”s? You know, Magmonsters, Meltimals and of course the terrifying Hell Manatees (Which are more properly referred to as Devil Dugongs).

  26. Brian

    So I finally worked upon enough curiosity to enter “bixbites” into google. Surprise: half of the results on the first page were trackbacks to this blogpost. (Fortunately there was also a pointer to a wikipedia article.)

  27. quasidog

    Very cool.

    I’m not sold on the idea that this is proof of ‘evolution’ at work however. I see change, and growth and such, and can see the links between life and minerals pointed out here, and can see how this change can be attributed to evolution as it is understood in the current popular view. It really depends on what flavour of evolution you what to describe I guess. I think what I really mean is I don’t see how this rules out the idea of a changing system governed by superior intelligence/s to humans.

  28. Nigel Depledge

    Quasidog said:

    I think what I really mean is I don’t see how this rules out the idea of a changing system governed by superior intelligence/s to humans.

    It doesn’t.

    However, consider this. We know of natural processes that can explain the entirety of the diversity of life around us today. There is no evidence of teleology in the development of the modern biosphere. There is no evidence of the existence of any “superior intelligence”.

    It is therefore reasonable to conclude that the processes that we have observed and that we understand have indeed shaped life into its present myriad forms.

    In the absence of supporting evidence, it is illogical to assume the existence of some kind of “superior intelligence”. If one does assume the existence of a “superior intelliegence”, this raises more questions that it answers (the nature of these questions depending on the kind of motivations one assigns to the “superior intelligence”).

  29. TheBlackCat

    I think what I really mean is I don’t see how this rules out the idea of a changing system governed by superior intelligence/s to humans.

    To put it another way, it doesn’t rule out such a being but it does render it entirely unnecessary and superfluous.

  30. quasidog
  31. In this neck of the Kalahari we have the Cradle of Humankind. Eat your heart our Phil.
    Here is a link to a podcast and some pictures.

    http://thinkingproblemmanagement.blogspot.com/2008/11/cradle-of-humankind.html

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