Bee Pollination
Bees are the most productive pollinators because they intentionally collect pollen for their larva.  Their legs have bristles that act as a pollen brush, with the first two pairs of legs brushing pollen from their hairy body and the third pair forming a pollen comb that collects pollen from bristles. The comb forces pollen into the pollen baskets on the legs. Bees have a sucking tongue (shorter than the butterflies and moths) that sips nectar, which the bees regurgitate into honey, which is food for the rest of the hive.

Photo by Wikipedia user Debivort. A bee collecting pollen on a rose. Accessed August 31, 2007 (Wikipedia)

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Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. Subject to disclaimers.

Notice the pollen that clings to the body of this bee.

Photo by Jon Sullivan at http://pdphoto.org/. Accessed August 31, 2007. Wikipedia

The secret of the Lady's Slipper
Many plants have developed complex paths that force pollinators to follow a certain route into and out of the flower.  This ensures that the anther and the stigma come into contact with the pollinator and in the proper order.  The Lady’s Slipper orchid is an example of this.

Showy Lady's Slipper (Cypripedium reginae Walt.)

Photos used with permission by Thomas G. Barnes (University of Kentucky) @ USDA-NRCS PLANTS Database / Barnes, T.G. & S.W. Francis. 2004. Wildflowers and ferns of Kentucky. University Press of Kentucky.

Hummingbird contributions to the garden.
Hummingbird pollinated flowers have a tendency to produce a certain amount of nectar that is drained by the birds. After the bird leaves to hunt for more nectar, the flowers will refill with more nectar, to encourage multiple opportunities to attract more birds and successful pollination.

Photo by author Mila Zinkova. A hummingbird and his flowers.
Accessed August 31, 2007 (Wikipedia)

Notice the long bill of the hummingbird. It is perfectly suited to reach down the long flower corolla to the nectar waiting at the bottom.

Photo by Wikipedia user Mdf. Black Chinned Hummingbird. Accessed August 31, 2007 (Wikipedia)

Photo by author Mila Zinkova. A hummingbird and his flowers.
Accessed August 31, 2007 (Wikipedia)

Pollination of the Yucca Flower by the Yucca moth
In a spirited tale of symbiotic relationships, the yucca moths are the only pollinator for the Yucca flower.  The female moth rolls a tight ball of pollen from the anther of one yucca flower, flies to another flower, and packs the sticky pollen into the stigma, fertilizing the flower.  She then lays her eggs in the flower ovary.  The moth larva and seeds develop simultaneously with the larva eating some of the seeds. 

Photo used explicitly for education use only with permission by author, Doug Backlund. Accessed from www.wildphotosphotography.com

The very delightful tale of the Bumblebee Orchid
The Ophrys orchid resembles a female bee, wasp or fly.  The males of this insect species emerge in the spring before the females.  The orchid’s blooming coincides with the emergence of the male insects.  The male insects are tricked by the flowers appearance and scent into mating with the orchid flowers.  During the visit to the flower, the pollen rubs onto the insect’s body.  When the insect visits another orchid, the pollen is deposited, thereby pollinating and fertilizing the flower.  In true fairytale fashion, the female insects emerges slightly later, mates with the male insect and also lays her fertilized eggs.

Bumblebee Orchid (Ophrys bombyliflora)

Photo by Wikipedia user JoJan. Bumblebee Orchid. Accessed August 31, 2007 (Wikipedia)

Long tongues and long flowers
The hawkmoth is a moth that hovers above the flower, inserting its long mouthpart into the floral tube to reach the nectar at the bottom.  Hawkmoth pollinated flowers don’t have landing platforms, traps, or other specialized adaptations.

Photo by Wikipedia user IronChris. Macroglossum stellatarum. Accessed August 31, 2007 (Wikipedia)

What kind of pollinator?
Charles Darwin found the orchid species, Anagraecum sesquipedale and observed the flower's very long nectar spur measuring up to a foot. He believed that a moth with a very long probobscis must be the pollinator, but was unable to witness the process. Later, scientists proved his hypothesis correct when they discovered the hawk moth species, Xanthopan morganii, with a proboscis length from 12-15 inches!

Malagasy Orchid (Anagrecum sesquipedale)

Photo by Larsen Twins Orchids.
Permission accessed August 31, 2007 through Wikipedia

Giant Hawkmoth from Madagascar (Xanthopan morganii)

Photo by Tony Watkinson. Permission generously granted through J. Pfahl and http://www.orchidspecies.com/