Jack pine cones
The mature cones of the jack pine (Pinus banksiana) open only when exposed to high temperatures, such as during a forest fire. A fire will probably kill most vegetation, so a seedling that germinates after a fire is more likely to receive ample sunlight than one that germinates under normal conditions.
Source
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"OpenStax College, Biogeography. October 17, 2013."
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OpenStax CNX
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