The beauty of Yellowstone National Park is everywhere – in the animals, trees, and plants; and in the calcium carbonate, algae, and archeabacteria.  What?  Not super familiar with calcium carbonate or archeabacteria?  I wouldn’t expect you to be.  So stay tuned for my story and short Biology lesson.

In the Northwest corner of Yellowstone is Mammoth Hot Springs – our second stop after entering the park.  Mammoth Hot Springs is a large complex of hot springs on a series of travertine terraces (series of white, flat, limestone surfaces deposited by hot springs).  It was created over thousands of years as water from the hot springs slowly cooled near the surface (a “cool” 80 degrees Celsius) and deposited calcium carbonate, a salt compound (over two tons of calcium carbonate solution flow through Mammoth each day). Because of the huge amount of geothermal activity (Yellowstone being a supervolcano over a hot spot and all), the travertine flourishes.  Mammoth itself isn’t directly over/within the caldera of the Yellowstone supervolcano – but the underground “plumbing” of the park is all connected – bringing hot water and geothermal vents to heat the water in the Mammoth corner of the park.  For this reason Mammoth, and the vast majority of Yellowstone National Park, are covered with signs reminding you not to touch the water for fear of scalding yourself.

And while the calcium carbonate (essentially the ingredient of white chalk that would have been used to write on a chalkboard in the olden days…or in a present-day portable) is the reason for the white or creamy colour of the travertine terraces, you would be remiss not to notice the rich yellows and orange colours that are found in the shallow flowing water running over the surfaces.  This is a combination of ancient algae and archeabacteria.  Now the vast majority of regular bacteria (Kingdom Monera for the bio nerds out there like me) could never survive at a temperature like this.  Part of the reason your body uses a fever as a immune response is that raising your body to a mere 39 or 40 degrees Celsius will kill off the majority of bacteria that would infect your body.  Most bacteria, like people, can’t like in 80 degree water.  Neither can fish, plants or animals.  But there are some strains of ancient bacteria, regular bacteria, cyanobacteria (bacteria that can do photosynthesis and convert carbon dioxide into oxygen, like trees to) and algae that THRIVE in hot water.  As lovers of hot water, we often refer to them as thermophiles (thermo = heat, phile = lover of).  They are some of the most fascinating to microbiologists, in addition to being the bacteria we know the least amount.  Some believed to be strains that could be millions of years old, they can survive in conditions that nothing else can.  We find them in deep thermal vents and in hot water assocaited with volcanoes.  But it is important to note that it’s not just the temperature of the water in Yellowstone that makes it an unusual place for bacteria to live.  It’s also the acidity.  Many of the springs, pools, mud pots and sulfur caldrons have extreme pH’s.  Some are equal to that of battery acid, and others to baking soda (highly alkaline).  These are extreme environments that are rare to find any sort of life in.  These various ancient bacteria and algae don’t just live and thrive in these extreme environments, but are also the reason for all the beautiful colours in Yellowstone.  The temperature and pH of the water changes what kind of bacteria will thrive there, and in turn, what colour bacteria will thrive there.  So throughout the park you will find almost every colour of the rainbow – beautiful and awe inspiring.  Prettiest bacteria you ever did see.

When I was in univeristy I took 2 consecutive semesters of microbiology.  And all year long my prof would go on and on about the marvels of Yellowstone.  Every class another story or family photo of a colourful pool and this “amazing” bacteria.  And most of us would roll our eyes – I mean for those of us who were 19 and more interested in the human element of microbiology, thermophiles just didn’t hold a candle to the “sexier” pathogens like E.coli, Rubella, or Ebola.  What I would give now to hear a lot more about themophiles and a lot less about Ebola in the news.  All to say – my prof was right.  And I too will one day “torture” my children with numerous summer vacations in Yellowstone, with lectures on the wonders of archeabacteria.  I may not go as far as Dr. Paulton, and show up with test tubes and a permit for water samples though…then again…once I have that microscope for the motorhome…

I digress.

Mammoth Hot Springs is beautiful.  The chalky white terraces rich with orange and yellow highlights look out of this world.  A series of board walks have been built above the terraces – as they are necessary for safety, and create an ease for walking through and exploring.  For those looking to visit, the parking lot at the bottom is easier to access and by far more popular.  But if you have a car and no trailer or motorhome, you can drive past this initial lot and around the bend to park at the top.  Not only do you get to see some amazing trees living (or dying) in field of calcium carbonate, but you get to view the terraces from the top.  It also means you will be hiking down, then back up, instead of up and then back down (this is just a matter of preference).  A lot of the key terraces are in the top half, which was great for me, who wasn’t quite adjusted to the altitude yet and happy to walk a few less steps if possible.  It’s not a difficult hike, being that it’s stairs and boardwalks, but also not wheelchair accessible from the top.  If you are new to being at 6700 feet (this was our first day in the park), you may want to take it easy and allow a lot of time.  Also drink lots of water.  Headaches and nausea are not uncommon being at this elevation.

It was great to enter the park through the Northwest entrance – not only for access to the boiling river and Roosevelt Arch (see here), but because the Mammoth Hot Springs were the furthest away from the rest of the major tourist sites, and it meant we didn’t need to spend hours the following days driving across the park to get back here (which could have been anywhere from 1-2 hours each way depending on the number of bison deciding to cross the road at any given time).

So if you like hiking, nature, national parks, boardwalks, Chemistry, Biology, microbes, Geology, hot springs, volcanoes, rocks, photography or calcium carbonate, add Mammoth Hot Springs to your Yellowstone vacation.  You won’t regret it.