Seeds are adapted for conditions other than geographic dispersal. When a seed arrives at its destination after dispersal, conditions may not be suitable for establishment of the plant. The delaying mechanism which prevents germination under adverse conditions is called dormancy. Seeds can remain in a condition of dormancy for varying lengths of time, depending on the species, until the correct balance of oxygen, moisture, and temperature triggers germination.
Viability varies greatly from species to species and may last only a few weeks or many years. Seeds of the cocoa plant are viable for only ten weeks. Some seeds, however, remain viable for decades or even hundreds of years. Seeds of the Indian lotus have been shown to remain viable for almost one thousand years. No claims for long-term viability have surpassed those made for the Arctic lupine, however: Seeds of this species have been successfully germinated after having been buried in the Arctic tundra for ten thousand years.
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