In the interest of accuracy, I am going to risk boring readers with a clarification of what determines the distance that a Miterwort seed travels. Jim Block, an outstanding nature photographer, obviously has a greater grasp of physics than yours truly. I attributed the distance traveled to the size of the raindrop and the distance it had traveled, but as Jim so clearly explains, only the the size of the raindrop effects the distance the seed travels.
Here is his explanation: The distance the seed travels is likely dependent on the mass and the velocity of the drop when it hits the seed. But the velocity of the rain drop is only dependent on its mass, not the distance it falls. That is because after it falls a relatively short distance it no longer gains speed since the air drag balances gravity and the drop moves at a constant “terminal velocity”. So in effect the distance the seed travels is dependent only on the mass of the drop. All drops of the same size arrive at the same velocity.
Miterwort, also known as Bishop’s–cap, is named for the resemblance of its fruits to the hats (known as miters) worn by bishops of the Roman Catholic Church. If you examine a flower closely, you will see its delicate, 5-pointed, snowflake-like beauty. Each flower is in the shape of a tiny cup, with dissected petals arising from the rim of the cup, resembling fine lacework. There is a glandular ring of nectar-producing tissue inside the cup which attracts small bees, flies and ants. Once pollinated, the flowers produce open seed-containing capsules. Water, not animals, is the dispersal agent for Miterwort’s seeds. The capsules orient themselves so that their opening faces upward. When it rains, the falling rain drops splash the seeds out of the capsules, dispersing them up to three feet away from the parent plant. The distance traveled by the seeds is dependent upon both the size of the raindrop and the distance that it has fallen before landing in a capsule.
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