Suposições incorretas na pergunta
De acordo com a Enciclopédia de Dunas , o mundo de Arrakis não é ecologicamente estéril. Existem plantas nativas que indicam que a fotossíntese tem ocorrido por quantidades geológicas de tempo.
The tip, the hollow once occupied by the tooth's nerve, customarily held a small amount of the most deadly poison available, most often a mixed derivative of the native desert plants.
E há também indicações (como salinas) de que o próprio mundo estava previamente encharcado, presumivelmente antes da introdução da truta da areia. Isso sugere que existem remanescentes subsuperficiais desses processos biológicos.
Então, quais são os vermes (e seus descendentes) comendo?
A Enciclopédia inclui uma descrição muito detalhada do ecossistema Dune e do ciclo de vida do Shai-Hulud.
Sandworms
Os grandes vermes da areia adultos são que consomem nutrientes diretamente do ar , além de alguns do processamento de sujeira. A energia necessária para catalisar essas reações químicas vem da eletricidade estática e do calor, ambos decorrentes do atrito. O resultado é um rendimento de uma entrada maior de energia do que a saída de esforço.
Respiration was accomplished through pores in the tough, silvery-gray outer skin. There was no circulatory system as such, since most of the nutrients were in the form of gases. Each segment had a series of membrane "baffles" to absorb nutrients.
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METABOLISM OF THE ADULT WORM: The adult G. Arraknis was a true autotroph, producing all of its nutritional needs from inorganic compounds on the planet surface. The energy to drive the synthetic reactions was obtained by the travel of the worm through free sand which caused an electrostatic charge differential. The resulting electrons passed to an electron acceptor believed to be a cupri-cyanide compound, the reduced form of which accumulated in the worm body. The electron donor was probably SiO₂, although the precise mechanism is unknown. Molecular oxygen was evolved during the reaction. The presence of water caused the electrons to be discharged abnormally because the anions and cations on the worm body dissolved in free water. Thus, water was a poison to the worm.
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The heat from the friction of the travel of the worm through sand drove the synthetic reactions to completion. Most of the nutrients produced were gaseous: methane, ethane, propane and butane, butyric acid, propionic acid, acetic acid, and formic acid. Excess gases not utilized for nutrients were literally ignited by the heat of sand travel. Thus, the worm always had a flame deep within the body cavity. The excess heat also aided in driving the synthetic reactions, keeping the nutrients in gaseous form for adsorption, and vaporizing any stray H2O.
Truta da Areia
A truta da areia menor parece estar comendo as substâncias químicas produzidas pelos vermes adultos
Many of the nutrients required by the sandtrout were breakdown products contributed by the female body. The sandtrout produced exoenzymes which digested the nutrients to fragments absorbable by the larvae.
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Nutrients were absorbed from water and air through the cell wall.
Em seus últimos estágios, a truta da areia se tornou autotróficos como seus parentes mais velhos, convertendo substâncias inorgânicas em orgânicas através de uma forma de síntese química.
The chemical reactions during the spice blow triggered changes in the surviving larvae, stimulating them to join their bodies in a premetamorphic stage. At this point, changes in metabolism began, so that the combined larvae became similar to the adult worm. Water gradually became toxic, and rudimen¬tary autotrophy developed.