Pompeii worm
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Pompeii worm ( Alvinella pompejana ) |
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| Alvinella Pompejana | ||||||||||||
| Desbruyères & Laubier , 1980 |
The Pompeii worm ( Alvinella pompejana ) is a maritime annelid worm that is native to the deep sea . Its habitat are hydro- thermal springs in the eastern Pacific Ocean.
features
Pompeii worms reach a length of 10 to 13 cm and are white-gray in color. They are dorsally covered with symbiotic bacterial colonies. These provide the worms with all the nutrients. In order to offer the bacteria a suitable ambient temperature, the worms cool their organism.
Way of life
The Pompeii worms live in paper-thin tubes that are attached to the outer chimney walls of black smokers at temperatures around 80 ° C (176 ° F). The “smoke” emitted from these hydrothermal springs contains not only hydrogen sulfide but also iron . At the high temperature in the tubes, the iron is dissolved in the water (Fe 2+ ) and reacts with the hydrogen sulfide to form iron sulfide (FeS). As a result, the poisonous hydrogen sulfide is only present in traces in the immediate vicinity of the worm and cannot harm the worm. The worms that live in groups have adapted to the extreme conditions of their environment; they are extremophiles .
Reproduction
A physiological mechanism has also been demonstrated for the eggs of the Pompeii worms that ensures the worms' spread. The fields of deep-sea hydrothermal springs are only active for about 20 years, then they dry up. In other, often distant places, however, the geotectonic forces along the mid-ocean ridges can create new hydrothermal fields. How the various, mostly sessile members of these extremophile communities can bridge the distances has not yet been researched for all species. For Alvinella , Florence Pradillon from the Université Pierre et Marie Curie in Paris showed that at two degrees Celsius, which is the “normal” water temperature under the pressure of the deep sea, the eggs stop developing and go into a kind of resting state. The 150 micrometer eggs can then be transported over long distances in the current. Only when they land again in the vicinity of a black smoker does the heat impulse from the hot springs initiate the further development of the eggs from around 10 ° C.
Discovery story
The Pompeii worm was discovered and described in 1980 by the French biologists Daniel Desbruyéres and Lucien Laubier near the Galapagos Islands . It got its name because, like the inhabitants of Pompeii , it lives at the foot of a volcanic chimney, in this case a black smoker. The genus Alvinella got its name from the manned deep-sea research boat DSV Alvin , from which the worms at the hydrothermal springs could be discovered and collected.
Individual evidence
- ↑ Cool neighborhood. May 3, 2005, accessed September 7, 2019 . In: Image of Science.
- ↑ George W. Luther et al .: Chemical speciation drives hydrothermal vent ecology. In: Nature. 410, 2001, pp. 813-816. (PDF)
- ↑ J. Ravaux, G. Hamel, M. Zbinden, AA Tasiemski, I. Boutet, N. Léger, A. Tanguy, D. Jollivet, B. Shillito: Thermal limit for metazoan life in question: in vivo heat tolerance of the Pompeii worm. In: PLoS One. 8 (5), May 29, 2013, p. E64074. PMID 23734185
- ↑ Biology: Cool Kids from Hot Worms. In: GEO. January 12, 2002.
Web links
- National Geographic article about the Pompeii worm (English)
- NCBI Taxonomy (English)