Annual vs. perennial plant evolution

Annuality and perenniality represent major life history strategies within plant lineages. These traits can shift from one to another over both macroevolutionary and microevolutionary timescales. While perenniality and annuality are often described as discrete either-or traits, they often occur in a continuous spectrum. The complex history of switches between annual and perennial habit involve both natural and artificial causes, and studies of this fluctuation have importance to sustainable agriculture.

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