Seed Dispersal Lab

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Seed Dispersal Lab
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Dispersal by Water

• The coconut can float on water for long intervals
  due to an air-filled pericarp layer.

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Dispersal by Water

• Mangrove seeds germinate while still attached
  to the adult plant. Seedlings are released into
  water.

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Dispersal by Water

• When its seed pod breaks open, Pond Iris
  seeds fall into nearby water. Seeds can float
  for long distances and germinate either in the
  water or when they become lodged in mud.

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Dispersal by Wind
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Dispersal by Wind

• The Red Campion ovary produces a pepper pot
  seed capsule with openings at the top. Wind
  shakes the capsule to scatter the seeds.

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Dispersal by Animals Fleshy Fruits

• Animals eat the fruit and deposit the
  undigested seeds at another location.

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Dispersal by Animals Attachment

• The cockleburr fruit has hooked barbs for
  attaching to an animals fur or a birds
  feathers.

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Dispersal by Animals Attachment

• Mistletoe has a sticky fruit that attaches to
  the beak and faces of birds. Birds scrape their
  beaks on tree branches to spread the seeds.

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Mechanical Dispersal

• The seeds are released when a ripe capsule of
  an Impatiens plant is touched.

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Mechanical Dispersal

• A thick husk that splits open to release a
  hickory nut.

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Todays Lab

• Survey of Seed Dispersal Mechanisms
• Observe and draw seeds
• Propose dispersal mechanism
• Design and test a wind-dispersed seed
• Distance Air stream test
• Time airborne Balcony test

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Worksheet

• Complete pages161-165 from lab manual
• Be sure your instructor checks your completed
  worksheet before you leave the lab