The Grand Prismatic Spring in Yellowstone National Park shows that bacteria can be beautiful. Those versatile prokaryotic organisms may be best known for causing pathogenic havoc, but when they hang around the sides of a warm Wyoming pond, the result is a glorious rainbow.
At 250-by-300 feet and up to 160 feet deep, the Grand Prismatic Spring is the largest hot spring in the USA. Its brilliant colors are the result of pigmented bacteria living on its perimeter. The hues change and become more or less vibrant depending on the kinds of bacteria thriving at the time.
The heat of the spring — it's 160 degrees Fahrenheit at the center — causes steam to waft and swirl, adding to the otherworldy look of the place.
Aquatic bacteria bonanza:
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