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Botany Greenhouse
The Agents of Evolution - Pollination Syndromes - BeeBee pollination (Melittophily)
Bat, Bee, Beetle, Bird, Butterfly, Fly, Moth, Snail&Slug, Water and Wind Bees are the most important group of flower-visiting animals. Both bee genders live on nectar, with the females also collecting pollen to feed the larve. Bees have mouth parts, body hairs, and other appendages specially fitted for collecting and carring these food materials. They can also quickly learn to recognize odors, colors, and outlines. The light spectrum that a bee can see is somewhat different than humans. They are able to see ultraviolet light, which is invisible to us, but it cannot distanguish shades of red, all of which appear black to a bee. Bees have developed a high degree of constancy to particular kinds of flowers. Such constancy increases the efficiency and in bees with narrowly restricted foraging habits, there are often conspicuous morphological and physiological adaptation related to the characteristics of the plant of choice. When contsant to this degree, bees exert a powerful evolutionary force for specialization in the plants they visit. There are some 20,000 known species of bees (honeybees, bumblebees, orchid bees), nearly all of which visit flowers for food.
Bee flowers that is, flowers that coevolved with bees, have showy, brightly colored petals, which are usually blue or yellow. They often have a distinctive pattern by which the bee can quickly recognize them. This pattern may include a "honey guide" special markings that indicate the position of the nectar. Bee flowers are never pure red, and, they often have distictive markings normally invisible to us.
In bee flowers the nectary is characteristically situated at the base of the corolla tube and is usually set below the surface which is accessible only to a specialized sucking organ. Bee flowers characteristically have a "landing platform" of some sort.
The anthers of some flowers release their pollen internally and must be shaken. Accomplishing this task is called "buzz pollination". Bees are the only pollinating agent to perform this.
Some of the evolutionarily more advanced flowers, in particular orchids, have developed complex passageways and traps that force the bee to follow a particular route into and out of the flower. This ensures that both anther and stigma come into contact with the bee's body at particular point and in the proper sequence.
An even more bizzarre pollination strategy has been adopted by orchids of the genus Ophrys. The flower actually resembles a female bee, wasp, or fly rather closely. Early in the spring, the males of these insect species emerge before their females. During this time these orchids are also in bloom which allows the male insect to attempt copulation with the orchid. During the course of their "sexual' visit, a pollinium may be deposited on the insect's body and thus transferred to the next flower that it visits.
Current Accessions:
Allamanda cathartica - Golden Trumpet {Apocynaceae}
Amorphophallus titanum - Titan Arum, Corpse Flower, Bunga Bangkai {Araceae}
Dalechampia roezliana - {Euphorbiaceae}
Passiflora caerulea - Blue Passion Flower {Passifloraceae}
