Définition : overall repetitive or reflective pattern in the body of one individual of this taxon. eg: bilateral symmetry, rotational symmetry, radial symmetry
Définition : Silt is granular material of a size somewhere between sand and clay whose mineral origin is quartz and feldspar. [ https://en.wikipedia.org/wiki/Silt ]
Définition : A group of species that exploit the same food resources, and/or use the same feeding or foraging methods. http://en.wikipedia.org/wiki/Guild_(ecology)
