التعريف: overall repetitive or reflective pattern in the body of one individual of this taxon. eg: bilateral symmetry, rotational symmetry, radial symmetry
التعريف: A lake or estuary that is formed at the mouth of a river where flow is blocked by a bar of sediments. It can be maritime (the bar being created by the current of a sea) or fluvial (the bar being created by the flow of a bigger river at the confluence).
التعريف: An organism that is dependent at least for part of its life cycle on dead or decaying wood or on other organisms that are themselves dependent on this resource.
التعريف: 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)
