When environmental conditions become unfavorable, tardigrades can enter a state of dormancy called “cryptobiosis,” which is characterized by desiccation, reduced metabolic rate, and enhanced resistance to conditions such as drought, low oxygen, salinity changes, or extreme temperatures. A dormant tardigrade, called a “tun,” may survive for long periods – 10 to 100 years, alternating between periods of activity and dormancy. (Nelson, 2002; Ruppert et al., 2004).