Study
Survival in extreme environments - on the current knowledge of adaptations in tardigrades
Møbjerg, N.; Halberg, K. A.; Jørgensen, A.; Persson, D.; Kristensen, R. M.
Acta Physiologica, 2011
A synthesis of tardigrade biology and the several distinct forms of cryptobiosis they enter — desiccation, freezing, oxygen deprivation and osmotic stress — together with body plan, feeding and ecology.
- Studied in
- Tardigrada
- Sample size
- review of tardigrade physiology and cryptobiosis
Tardigrades are a phylum of around 1,300 described species, most under a millimetre long, with four pairs of legs ending in claws and a piercing feeding apparatus. They are aquatic animals requiring a film of water to be active, found in moss, lichen, leaf litter, soil, freshwater and marine sediments. Cryptobiosis takes several distinct forms with different triggers and mechanisms; anhydrobiosis is the best studied.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Tardigrade extreme tolerance is a set of specific reversible states rather than a general robustness, and the states differ in mechanism.
How NatureHQ reads it
The framing correction the whole subject needs. "Extremophile" is the wrong word for a tardigrade: an extremophile lives in extreme conditions, and a tardigrade lives in a damp piece of moss and *survives* extreme conditions by switching itself off. The distinction is not pedantry — it explains why an active tardigrade is a fragile little animal and why every impressive result in the literature begins by drying one out first. It also matters that cryptobiosis is plural: freezing tolerance and desiccation tolerance are different states with different mechanisms, and results do not transfer between them.
- A review across a phylum where most species have never been studied physiologically.
- Marine tardigrades in particular are poorly characterised and largely lack anhydrobiosis.
- Predates the genomic work that identified specific protective proteins.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: Wiley journalsPublished in a Wiley journal.
doi.org/10.1111/j.1748-1716.2011.02252.x
This reference was resolved automatically against Crossref on 2026-08-11.
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