Tardigrades: An Example of Multicellular Extremophiles

Part of the Cellular Origin, Life in Extreme Habitats and Astrobiology book series (COLE, volume 27)


Life has expanded its living range into almost every environmental niche imaginable on Earth. These include habitats of extreme temperature, pressure, and pH ranges, and environments with low nutrient and oxygen availability, high salinity, and radiation exposure. However, not only microbes can survive in these harsh environments but also some higher complexity organisms such as fungi, plants, and even animals. Among the toughest animals in this respect are tardigrades. These microscopic animals, also called “water bears,” are metameric invertebrates that live in a wide range of habitats such as in marine, freshwater, and terrestrial ecosystems. They possess various adaptation mechanisms such as cryptobiosis, which makes them astonishingly resistant to desiccation, extreme pressures, temperature, and radiation conditions. Thus, these multicellular organisms should be considered when assessing survival rates and evaluating analogue organisms for space travel and in extraterrestrial environments.


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Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  1. 1.School of Earth and Environmental SciencesWashington State UniversityPullmanUSA
  2. 2.The Hebrew University of JerusalemJerusalemIsrael

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