Thermophilic Bacteria

Small ridges of rock filled with water
The travertine terraces in Mammoth Hot Springs host thermophilic Cyanobacteria.



The word “Bacteria” is often associated with disease, but only a few kinds of Bacteria cause problems for humans. The other thousands of bacteria, although all simple organisms, play a complex role in Earth’s ecosystems. In fact, Cyanobacteria were responsible for the oxygenation of our atmosphere. They were the first photosynthesizers, converting light energy into oxygen more than 2.4 billion years ago. Without Bacteria, in particular Cyanobacteria, humans would not be here.

While some Bacteria perform photosynthesis, others depend on chemical energy that is released when compounds like hydrogen or sulfur react with oxygen. This energy is then used to convert carbon dioxide into biomass (chemosynthesis). For example, Thermus sp. may also be able to oxidize arsenic into a less toxic form.

Individual Bacteria may be rod or sphere shaped, but they often join end to end to form long strands called filaments. These strands help bind thermophilic mats, forming a vast community or miniecosystem. Other groups of Bacteria form layered structures resembling tiny towers, which can trap sand and other organic materials.


Source: Data Store Collection 7681. To search for additional information, visit the Data Store.

Archaea are found in place like the mudpots of Mud Volcano.
Thermophilic Archaea

Archaea are the most extreme of all extremophiles.

Green colors line a thermal runoff pool.
Thermophilic Eukarya

Microscopic plants and animals live in the extreme environments of Yellowstone's hydrothermal features.

Blue waters of Congress Pool are host to thermophilic viruses.
Thermophilic Viruses

Viruses, a logical part of thermophilic ecosystems, have been found in some pools in Yellowstone.

Orange-colered bacterial column growing in geyser runoff water.
Thermophilic Communities

Thermophilic communities are very diverse, depending on the microbes living there, the pH, and the water temperature.

View of the "Burns Cliff" on Mars showing rock layers with evidence of water reactions.
Thermophiles in Time and Space

Yellowstone's hydrothermal features and thermophilic communities are studied by scientists searching for evidence of life on other planets.

A dark blue hot spring with a white crested edge rimmed by orange water.
Life in Extreme Heat

Hydrothermal features are habitats for microscopic organisms called thermophiles: "thermo" for heat, "phile" for lover.

Last updated: October 15, 2020

Park footer

Contact Info

Mailing Address:

PO Box 168
Yellowstone National Park, WY 82190-0168



Contact Us