Diatoms for Dummies

Photomicrograph of a diatom test

Here at the Antisocial Network, we get butterflies in our collective gut when we run across someone pretending to be knowledgeable and authoritative, but failing because they've said something just plain stupid. We don't mean sticking your foot in your mouth up to the ankle; anyone can undergo a brain fart and say something dumb out loud. No, we're talking about the kind of rookie mistake that comes from bad research or, as in the case of Alisha Vargas at HubPages.com, from cribbing information from multiple sites but not bothering to proofread the resulting text for conflicts. Alisha pulled off this stunt in the article she called "The Wonderful World of Diatoms," which – unless you read it closely – actually made her look kinda smart-like.

We say "smart-like" because, as we read through the content, it became fairly obvious that Alisha's just doing a workmanlike copy-reword-paste job. Some of the clues? lines like

• "Diatoms live in both salt and freshwater, and some can even live in damp places": Does this mean salt and fresh water aren't damp?
• "Diatoms are the principal constituent of plankton": Umm, no, diatoms are one of the most common types of phytoplankton, but they're not "the principle constituent."
• "Diatoms are really useful in carbon dating sag ponds, which are ponds created when faults move": We're not sure how useful siliceous shells are for carbon dating, since they contain no carbon...

That last is a most important observation. See, right at the beginning of her article, Alisha copied a line from someone that said,

"Diatoms form shells or walls, called frustules, around themselves out of silica, so it's almost like their frustules are made of glass or quartz."

"...almost like [they're] made of glass or quartz"? Dummy, what do you think silica is? Crystalline silica is quartz while amorphous silica is glass. You left out opal, by the way... but the important point is that the little critters construct their houses out of silicon dioxide (SiO2). Please note that there is not a "C" anywhere in that chemical formula.

Got that? OK: so if diatoms construct their shells – excuse us, frustules – from silica, then how can a giant pile of dead diatoms sequester carbon, huh? Yup, you said this, Alisha: "Diatoms sequester excess carbon by using it in their shells and then dying and falling to the ocean floor, where they then may fossilize and become rock... It's thought they may be key to slowing or reversing global warming due to the way they capture carbon... Many scientists are pondering the idea of seeding the seas with iron, which is difficult to come by in the ocean and needed for diatom reproduction. This may increase the numbers of diatoms and they could then sequester even more carbon dioxide."

Vargas is correct: there is such a theory – although scientists don't much disagree over whether it would work; they argue about possible unintended consequences. Where Alisha goes dumbass is in claiming that scientists want to increase diatom growth. The model calls for increased growth of phytoplankton, which includes plankton that build shells from calcium carbonate (CaCO₃) – see that second "C" in there, Alisha? That's a sequestered carbon atom!

Based on her little treatise, Alisha's grades are a C in zoology and an F in chemistry, Alisha. Sorry, but that makes her a prime candidate for the Antisocial Network's Dumbass of the Day.

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