The Case for a Creator: A Parade of Horribles, Part II

The Case for a Creator, Chapter 7

Earth’s Size

Gonzalez’s next assertion strikes me as highly dubious. He claims that, if the Earth were larger than it is, the higher surface gravity would tend to smooth out mountains and ocean basins, producing a perfectly spherical planet with little surface relief. (He provides no numbers on how much bigger the planet could be before this happens.) This would result in a “water world” whose surface was evenly covered by a shallow ocean, and “a water world is a dead world” [p.181] because there would be no continental weathering to wash mineral nutrients into the oceans. “In a water world, many of the life-essential minerals would sink to the bottom. That’s the basic problem.” [p.181]

Yet again, evolution is smarter than the creationists. Vital minerals sinking to the ocean bottom would suit hydrothermal vent communities just fine – the ocean-bottom ecosystems that use minerals spewing from volcanic fissures in the ocean floor and subsist on chemical energy rather than sunlight. Some biologists even believe that these “black smokers” are where life on Earth began.

“Besides, the salt concentration in a water world would be prohibitively high. Life can only tolerate a certain level of saltiness.” [p.181]

Gonzalez’s argument here is that in continental environments like marshes, ocean water can evaporate and leave salt deposits behind, preventing the seas from becoming too salty, but this couldn’t happen in a water world.

This reminds me of those young-earth creationist lists that offer various “proofs” which directly oppose each other. One of my favorites was the list that claimed, on the one hand, that the Earth must be young because if it was old, erosion would have worn away all the mountains, and on the other hand, the Earth must be young because if it was old, volcanism would have created mountains much higher and larger than we see today.

Gonzalez, allegedly a scientific authority, has made the same elementary blunder here. Salt comes from continents! If we lived on a water world, with no continents to erode and wash material into the ocean, there would be no source of salt. And, yet again, Gonzalez overlooks the fact that some species of Earthlife already can cope with the very salty environments that he claims would make life impossible. They are called halophiles. The green alga Dunaliella salina, for example, can live in water with a 30% salt content (ocean water is about 3% salt).

Plate Tectonics

Next on the list is plate tectonics, which Gonzalez claims is a necessary ingredient for life. The book correctly describes the cause: the natural heat of radioactivity, which keeps the earth’s interior hot and causes the continental plates to drift on an underlying sea of semi-molten rock. The churning of the Earth’s iron core also creates a dynamo effect that’s responsible for the planet’s magnetic field.

“The magnetic field is crucial to life on Earth… If we didn’t have a magnetic shield, there would be more dangerous radiation reaching the atmosphere.” [p.183]

But every few hundred thousand years, the Earth’s magnetic field reverses – in other words, the magnetic north and south poles exchange places. (We know this from the geological record: iron crystals in lava align with the geomagnetic field like tiny compass needles, then are frozen in place when the lava cools and hardens.) A full magnetic reversal takes several thousand years from start to finish, and while it’s happening, our planet has a greatly weakened magnetic field. Life has obviously survived these events, and no mass extinctions are known to be correlated with pole reversals.

Gonzalez also says that plate tectonics plays a vital role in the carbon cycle, subducting carbonate minerals into the mantle and then reemitting them from volcanoes as carbon dioxide. This does play a role in creating the environment for life on Earth, but again, there’s no reason to believe it’s an absolute necessity. Carbon dioxide levels have been much higher in past geological periods, and this too did not lead to the extinction of all life.

The Galactic Habitable Zone

Gonzalez’s final assertion has to do with the Earth’s location in the galaxy. He says that Earth is located in a “safe area” [p.169] of the Milky Way, far from the central supermassive black hole and from active star-forming regions, both of which would have dangerously high levels of radiation. On the other hand, the galaxy’s outer regions and globular clusters are composed mostly of older, cooler stars and lack the heavy elements that are cooked up by supernovae and that are needed to form planets and life:

“…[Y]ou can have a whole globular cluster with hundreds of thousands of stars, and yet there won’t be a single Earth.” [p.170]

Clearly, Gonzalez has a strong point here. Globular clusters lack heavy elements, are too gravitationally unstable, and in all other ways are completely unsuitable for planets. Therefore, we can’t possibly have discovered PSR B1620-26b, an extrasolar planet orbiting a dual-star system in the globular cluster Messier 4.

Now, I’ll grant that Gonzalez is not entirely wrong: the low metallicity of globular clusters does make them a poor environment for planetary formation. (Another factor may be the stronger ultraviolet radiation in globular clusters that would dissipate protoplanetary disks of gas and dust.) But the existence of PSR B1620-26b shows that it is not impossible. In fact, not only does this planet exist, it’s thought to be extremely old – over 12 billion years, over twice the age of the Earth – and presumably formed in an era of the universe when heavy elements are sparser than they are now. This strongly implies that something is wrong with Gonzalez’s confident assertions about the probability of planet formation, and very probably indicates that the process is not as difficult or as unlikely as he implies.

As far as extremes of radiation – as with extremes of temperature and salinity, which were discussed in the previous part – once again the creationists have underestimated life’s adaptability. There are already Earth species that can survive levels of radiation well in excess of what humans can tolerate. The reigning champion is Deinococcus radiodurans (see also), a bacterium which can survive a dose of 15,000 grays (10 grays is lethal to a human). D. radiodurans has been found living in the cooling water of nuclear reactors. The microscopic animals called tardigrades are nearly as resilient, able to withstand not just high doses of radiation but also high pressure, the vacuum of space, and temperatures well above boiling or just above absolute zero.

Of course, these are microscopic creatures, not large, complex life. But how do we know that the adaptations they possess couldn’t have been transferred to creatures more like us? The Earth’s environment has never been so extreme as to provide an evolutionary pressure in that direction, but there’s no obvious reason to believe it’s impossible. (Withstanding high doses of radiation is mainly a matter of DNA repair mechanisms.)

The creationists who parade these horribles before us want us to believe that life is fragile, just barely clinging to existence, and even a small perturbation to the environment would spell our doom. (One wonders why they’re not more fervent about opposing global warming, if that’s so.) But the evolutionary record reveals precisely the opposite: life is a tenacious phenomenon, able to survive in a wide variety of environments from the frozen arctic to the boiling-hot vents on the ocean floor, from arid deserts to salt-saturated ponds, and even in the vacuum of space. It’s worth wondering whether, if creationists like Strobel were willing to acknowledge the true breadth and depth of life’s history, they might be willing to give it more credit for being able to flourish in unlikely places.

Other posts in this series:

About Adam Lee

Adam Lee is an atheist writer and speaker living in New York City. His new novel, Broken Ring, is available in paperback and e-book. Read his full bio, or follow him on Twitter.

  • Dan

    There are good reasons why Gonzalez didn’t get tenure and has wound up in the backwaters of academia. If you’d been on his dissertation committee we might not be dealing with his quackery now.

  • Jim Baerg

    http://www.worlddreambank.org/P/PLANETS.HTM
    has some interesting exercises in science fiction world building, including some thought experiments on how different a world could be from Earth & still support intelligent life. See Lyr for how the very large water world would be just fine.

  • http://bamoon.com BrianM

    When a creationist talks about “life”, I get the impression that they should be understood as meaning “life which can worship God”. In other words, bacteria and algae aren’t actually “life” as they understand it. Because, I mean, c’mon! Only humans and cute fuzzy animals like puppies and kittens get into Heaven!

  • Dennis N

    He gets close to stating his entire argument, but doesn’t go far enough:

    “The magnetic field is crucial to life on Earth for it to be exactly as it is now.”

    That would be an accurate statement. He doesn’t accept that life could be any way except the infinitely improbable way it is now. It’s true, the exact configuration we have now is mind-breakingly unlikely, and no one is disagreeing with him. He’s beating up a straw-man here. I would concede every one of this points about how unlikely we are, and he’d still be wrong. Since he doesn’t understand/accept evolution, he can’t imagine life existing in any other state than what he sees with his eyes. It’s very ironic that the very people who believe imaginary fairy tales don’t have much imagination.

  • http://www.WorldOfPrime.com Yahzi

    I thought the role of the magnosphere was to protect our atmosphere from being stripped off by the solar wind (which is why Mars, which is magnetically inert, no longer has an atmosphere).

    If that’s right, then we do need a magnosphere, but not for the reason Gonzalez says.

  • Thumpalumpacus

    To be fair, the extremophiles cited generally have the advantage of life already being extant. The difficulties of replicant molecules to form the meaningful symbioses presumably needed to bootstrap into life, for instance, might be immeasurably more difficult in a hyperradiated world.

  • Reginald Selkirk

    “a water world is a dead world”

    I saw that Kevin Costner movie, and in a way he has a point.

  • http://she-who-chatters.blogspot.com D

    But you don’t understand, Ebon! Those tardigrades and halophiles can only be the way they are now, because that’s how they were Created, and macroevolution doesn’t happen. Any time you think you see macroevolution, you’re really just seeing microevolution. The world hasn’t been around long enough for all that macro nonsense to have happened! And as for your fancy iron whatevers, clearly that didn’t happen the way you say it did, becaue the Earth isn’t old enough for that, either. There’s just no way that the things you say have happened could have happened. Sure, things might have gone that way in a similar Universe that was actually billions of years old and without a Creator; but we live in a Universe that does have a Creator and is only five to ten thousand years old, so your “just-so” story can’t possibly be true.

    See, they really do look at the same evidence and interpret it differently. The crucial difference, however, is that they interpret the World as misleading and their fairy tales as authoritative. Because, y’know, God would never lie to their ancestors, and their ancestors would never lie about God, so it has to be true, just ‘cuz. All you do is to interpret the World as authoritative and their fairy tales as misleading, which is really just the other side of the same coin (ARGH I FEEL SO DIRTY WRITING THAT!), but that’s disrespectful and mean, so you can’t possibly be right. Therefore, science doesn’t work, and God heats up your burritos in the microwave because the principles on which microwaves work are the same principles by which we know the Big Bang happened.

    What a bunch of vapid fucking morons.

  • jemand

    @Yahzi, no, mars is much smaller mass wise than the earth which explains it’s smaller atmosphere (which it actually still does have), Venus is much closer in mass to the earth and it has a PLENTY big atmosphere despite having a very small or nearly nonexistent magnetic field. (It could be in the midst of a polarity reversal, as the internal construction of the planet does seem to be similar to earth’s)

  • http://anexerciseinfutility.blogspot.com Tommykey

    With regard to Mars, methane emissions have been detected and one possibility offered is that there might still be microbial life on the planet that is emitting the methane.

    Regarding the Galactice Habitable Zone, why would God need to make a Galactic Uninhabitable Zone anyway?

  • Justin

    Please Tommykey, obviously God didn’t create the galactic uninhabitable zone – Satan did, to subvert your faith. Right in between burying the dinosaur bones and inventing interprative dance.

  • Jim Baerg

    #9 Jemand

    So I’m not the only one who thinks that the thick atmosphere of Venus is a good argument against the notion that planetary magnetic fields help keep the atmosphere in.

  • http://www.daylightatheism.org Ebonmuse

    Jim (#2), thanks a lot for that link! That is a truly amazing website, and I’m going to waste many happy hours reading it. :)

    The difficulties of replicant molecules to form the meaningful symbioses presumably needed to bootstrap into life, for instance, might be immeasurably more difficult in a hyperradiated world.

    Granted, Thump. Then again, it depends where life got started, doesn’t it? If the first replicators began in a black-smoker vent, as some biologists believe, then it might not be such a problem – a few miles of water overhead ought to be a pretty decent shield against harmful radiation. The same applies if life got started in deep cracks in rock, or down in the crust. It’s only the warm-shallow-pond scenario where high radiation levels pose a problem for abiogenesis, I would think.

    Also, on the topic of atmosphere and plate tectonics: It’s not only Venus that has an atmosphere. Saturn’s moon Titan has an atmosphere slightly denser than Earth’s, even though it has no magnetic field.

  • colluvial

    . . . once again the creationists have underestimated life’s adaptability.

    It may well be that there’s life on this planet only through some highly improbable, quirky set of circumstances (and somewhat less improbable if we ever find other earthly life forms with whom we don’t share a common ancestor). But for Gonzalez to assert that if conditions were not exactly as they have been then no form of life could have arisen, assumes that he knows what conditions were necessary for the origin of life. As you’ve pointed out here, there are many extreme conditions in which some form of life is quite comfortable, so how could we assume the presence of those conditions would have prevented life from arising?

    Does Gonzalez have some philosophical basis for this line of argument other than: If things were different, then the end result would be different, and we know that we are what we are, so how could that be, and that’s why goddidit?

  • Thumpalumpacus

    Yep. I find the vent-origin hypothesis attractive.

    At any rate, the fact that so many special conditions are “required” by this argument rather points up how unfinely tuned is the Universe at large.

  • Scotlyn

    Some biologists even believe that these “black smokers” are where life on Earth began.

    Actually, this paper is one of a number by William Martin and Michael Russell, the chief proponents of the idea that life may have first arisen from normal chemistry taking place in a cooler object, about 40degC, the alkaline hydrothermal undersea vent. Black smokers are much hotter and have a different chemistry, although these do support an amazing variety of living things. The alkaline vent theory (also known as the Iron-sulphur hypothesis, or “metabolism first” is a fascinating theory covered more briefly here and here. What is so attractive about Russell & Martin’s work, is that they have carefully demonstrated, in paper after paper, a detailed step-by-step scenario by which ordinary chemistry, within the peculiar set-up provided by the alkaline hydrothermal vent, could have lead to the metabolism at the heart of every cell, and from there to fats (cell walls), purines(RNA), ATP or similar energy storage molecules and proteins.

  • http://steve.mikexstudios.com themann1086

    There’s also a physics fail at the beginning, in that larger planets don’t necessarily have higher gravities. In fact, a planet with Earth’s mass but a radius 50% larger would have a surface gravity value of 4/9ths ours. Granted, most planets have similar enough densities that the gravitational field is proportional to the radius*, but it doesn’t have to be that way.

    *Fg ~ M/r^2, but M ~ 4/3 pi r^3, so Fg ~ r

  • Ruana

    Something dawned on me while I was reading this; on the one hand, we have creationists pouring scorn on evolution theory because scientists can’t go back in time and watch it happening. On the other, we have Gonzalez confidently asserting that life would be impossible on a planet that was like Earth except for conditions x, y or z. And yet I have trouble visualising any of the aforementioned creationists contemptuously dismissing his arguments on the basis that he can’t produce evidence from any such actual observable planets.

    Please do correct me if I’m wrong about that. Likewise, if it’s not actually such a glaring double standard as it seems to my quit-science-too-early self, let’s hear it.

  • http://www.undergroundgames.dk Slater

    Ruana: What, you’re actually surprised these people are hypocrites?

  • Ruana

    Goodness, no! I just like to be sure.


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