title: [2 rules on the life cycle of trematodes in the ecosystem].
abstract: Rule I: The more advanced in its primary evolution a life cycle is, the greater the participation of the animal component in it is. Parallel to that, most often the direct effect of the non-living component of the ecosystem on the cycle running is decreased. Rule II: In the majority of secondarily evolved life cycles of trematodes the following occurred in comparison with their initial life cycle: a) either a decrease of the direct effect of the non-living component of the ecosystem on the cycle running; b) or a decrease of the participation of the animal component of the ecosystem in the cycle; c) or most often a decrease of both together.
mesh_terms: D000818:Animals; D005075:Biological Evolution; D004463:Ecology; D005210:Fasciola hepatica / Q000254:growth & development; D006790:Host-Parasite Interactions; D009891:Opisthorchis / Q000254:growth & development; D014200:Trematoda / Q000254:growth & development*
vernacular_title: Zwei Regeln zu den Lebenszyklen der Trematoden im Okosystem.