Marmots are relatively large ground squirrels in the genus Marmota, with 15 species living in Asia, Europe, and North America. These herbivores are active during the summer when often found in groups, but are not seen during the winter when they hibernate underground. They are the heaviest members of the squirrel family.

Most marmots are highly social and use loud whistles to communicate with one another, especially when alarmed. Marmots mainly eat greens and many types of grasses, berries, lichens, mosses, roots, and flowers.

A number of historians and paleogeneticists had postulated that the Yersinia pestis variant that caused the pandemic that struck Eurasia in the 14th century originated from a variant for which marmots in China were the natural reservoir species.

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