Thermophilic Viruses

A blue steaming pool surrounded by pale rock
A virus was discovered in Congress Pool, shown here, at Norris Geyser Basin. It was infecting the archaeum Sulfolobus.


A magnified image of a blue, teal, and orange shape
This virus parasitizes Sulfolobus.

Thermal Biology Institute, Montana State University

Like bacteria, the word “virus” often conjures up images of sickness and death. However, relatively few of the many types of viruses cause problems for humans. None of the thermophilic viruses in Yellowstone should cause problems for human health—our bodies are too cold, for one thing.

Unlike microorganisms in the three domains, viruses are not considered to be alive. (Yet they are still called “life forms.”) They have no cell structure, only a protein “envelope” that encloses a piece of genetic material. They cannot reproduce on their own. Instead, a virus inserts itself into a host cell and uses that cell’s nutrients and metabolism to produce more viruses.

Scientists suspect many viruses exist in Yellowstone’s hydrothermal features because they would be a logical part of the thermophilic ecosystem. One kind was discovered in Congress Pool, at Norris Geyser Basin. It was infecting the archaeum Sulfolobus. Another kind of virus has been identified in pools near Midway Geyser Basin.


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.

Traverine terraces of Mammoth Hot Springs host thermophilic bacteria.
Thermophilic Bacteria

Almost all hot springs and geysers host thermophilic bacteria.

Green colors line a thermal runoff pool.
Thermophilic Eukarya

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

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

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