The Biological interaction reference article from the English Wikipedia on 24-Apr-2004
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Biological interaction

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In an ecosystem, no organism is living as an autonomous entity, isolated from its surroundings. It is part of is environment, rich in non living elements, rich in other organisms, from its species or another, with whom it is in interaction. Relationship between two species may be very different from one eating the other (predation), to both living together with mutual benefit (symbiosis).

Examples of interations are