Fire Pines

Exemplified by the Bishop Pine of California, Fire Pines produce sealed cones containing mature seeds.

The whole cone drops to the ground and lies there, sometimes for years.  Squirrels can't get inside, they are dry and secure, until...

Fire!

When a forest fire sweeps through an area, the cones are weakened by the intense heat.  When they cool, they open, and the seeds fall out, ready to grow in an area newly cleared of rival plants, with no predating creatures trying to eat them.

In an era when the oxygen content of the atmosphere was higher, and forest fires were regular occurrences, this adaptation must have been very successful.  Now however, forest fires are rare, and getting rarer still as humans prevent them or put them out.  Fire pines, one of the most interesting of the plant adaptations, are rare and likely to go extinct.

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