Jason E. Andersen

Subtle snowflake special

I know this is something that you (probably) don’t want to think about, but snow is right around the corner. Aside from the driving complications, and removal of said substance, snow is pretty cool. Ha! Puns!

You may recall that snow (and really all forms of precipitation) form around some central piece of material, upon which the water collects. These materials are called nucleators. Dust, pollen, and smoke are all common nucleators. Do you know what else is an incredibly common nucleator? Bacteria! Carried aloft by winds, bacteria freely float through the air, sometimes soaring to great heights. While at altitude, the bacteria intermix with moist air and, depending on the conditions, you get clouds, rain, hail, and/or snow. 

If you’re paying attention, and I hope you are, you probably realize that this is the exact same process held by other nucleators. The same is true for dust, pollen, and whatnot. They go up in the air, collect water, and fall back to earth as some sort of precipitation. And that is what brings us to our fun fact.

Bonus Fun Fact: Some species of bacteria secrete a protein that helps to grow ice crystals around them, so they can more easily become snowflakes. Yes, some bacteria have evolved to be snow! Nature is crazy!

While floating around in the atmosphere, these bacteria take an active approach to returning to earth. I mean, what if they stay up there forever? They could freeze to death! Sensing their peril, these microbes secrete a special protein that mimics the structure of ice. When these proteins then encounter water molecules, bam(!), crystal formation! The snowflake forms around the bacteria, eventually becoming heavy, and returning to earth as snowfall. It also has the added bonus of being a great transportation mechanism, which is why bacteria that do this are found all over the world where snow occurs.

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When there is a picturesque gentle snowfall this winter, you may be tempted to stick your tongue out and catch a snowflake. At that moment, I implore you to think about this. There may be a bacterium in that snowflake. It worked very hard to make it and, probably, doesn’t want to be eaten.

Think of the bacteria.