Soil Nematodes of the Antarctic Dry Valleys

Although many people are not familiar with nematodes’ existence, they are more common than one may think. They are very successful roundworms that are found all over the Earth. Due to their small size, one may not take the time to notice them. However, they are worthy of our attention for a couple reasons. First, particular species of nematodes are gaining attention as a fish larvae food. Secondly, they are very hardy creatures that have adapted to unusual and extreme environments. Surprisingly, many readily grow on banana tree roots and unpasteurized vinegar. Some even dwell in one of the coldest environments, such as the Antarctic Dry Valleys. While considering these factors, one may wonder why such a simple creature can survive in such various conditions. Unlike their simple body, the factors that lead to their survival and success are not simple. This is especially true for the soil nematodes that dwell in the Antarctic Dry Valleys.

While the reasons that lead to their success is quite complicated, it is very obvious that they have obtained the secret to survive in such harsh conditions. Treonis and Wall (2005) explains by stating the fact that “soil nematodes are capable of employing an anhydrobiotic survival strategy in response to adverse environmental conditions” (Pp. 741-750). As the name suggests, the Antarctic Dry Valley is very dry. For example Treonis and Wall (2005) states that, “the McMurdo Dry Valleys of Antarctica are the coldest and driest terrestrial ecosystem on Earth” (Pp. 741-750). Thus, the anhydrobiotic survival strategy of the soil nematode came in very handy while trying to survive in such harsh conditions.

Although the anatomy and physiology of soil nematodes and humans are extremely different, the concept of homeostasis is very similar. When a person is cold, he or she will try to retain heat by decreasing heat loss. This commonly results in cuddling or curling action in order to decrease the surface area of the skin, which is where the heat is lost from. This same effect was observed in the soil nematodes in dry areas. The soil nematodes tried to retain the water by decreasing the surface area of its cuticle. Treonis and Wall (2005) explains this concept by stating that “coiling reduces the surface area of the nematode cuticle that is exposed to the environment and slows drying” (Pp. 741-750). When the soil nematode coils itself, the overlapped part of the cuticle is able to retain its moisture better than the exposed part of the cuticle. These very simple mechanisms seen in both soil nematodes and humans are very interesting. For soil nematodes, the research reported by Treonis and Wall (2005) suggests that “coiling confers survival benefits” (Pp. 741-750). From these results, it makes one notice the importance of the homeostatic mechanisms that can easily be taken for granted. Similarly to the soil nematodes, these mechanisms are what enable us to survive under various conditions.

References

Treonis, A., Wall, D. (4-8 Jan. 2005). Soil Nematodes and Desiccation Survival in the Extreme Arid Environment of the Antarctic Dry Valleys. Integrative and Comparative Biology. Oxford Journal, Volume 5, Pp. 741-750.

Posted on August 16, 2014 and filed under News.