Anhydrobiosis and Freezing-Tolerance: Adaptations That Facilitate the Establishment of Panagrolaimus Nematodes in Polar Habitats

Researchers discovered that several Panagrolaimus nematode strains, including those from polar habitats, possess both anhydrobiosis and freezing-tolerance traits, enabling survival in extreme conditions. These adaptations allow them to endure water loss and intracellular ice formation while also inhibiting ice crystal growth. Phylogenetic analysis revealed that these traits evolved early in the lineage, with some Antarctic and Surtsey isolates showing robust freezing tolerance without specialized polar adaptations. The study suggests that the colonization of harsh environments like Ross Island and Surtsey by these nematodes may stem from recent 'ecological fitting' rather than evolutionary specialization.

McGill, L. M., Shannon, A. J., Pisani, D., Félix, M.-A., Ramløv, H., Dix, I., Wharton, D. A., & Burnell, A. M. (2015). Anhydrobiosis and Freezing-Tolerance: Adaptations That Facilitate the Establishment of Panagrolaimus Nematodes in Polar Habitats. Plos One, 10(3), e0116084. https://doi.org/10.1371/journal.pone.0116084