Deceptive flowers

The third pattern of temporal fragrance variation centers on the role of odor changes in deceptive flowers, such as nectarless orchids (reviews Dafni, 1984 Ackerman,... 

Flowers of some orchids mimic both the appearance and sex pheromone of virgin females of certain species of bees or wasps. This sexual deception results in pollination by male hymenoptera that would not normally visit flowers. Japanese honey bee drones (Apis cerana japonica) cluster on the oriental orchid (Cymbidiumpumilum) while on their mating flights [ 134]. By comparing volatile profiles of orchids and the female hymenoptera they mimic, or by GC-EAD and GC-MS analysis of orchid volatiles, several compounds have been identified that may mediate this attraction for the solitary bee Andrena nigroaenea [135, 136] and the scoliid wasp Campsoscolia ciliata [135]. 

Even in the Renaissance, the deceptively realistic imitation of nature in art n/as considered proof of an artist s superior technical ability. The Field of Flowers playfully takes up this artistic tradition of imitating nature and sets the petals in motion, causing them to rhythmically open and close. The photovoltaic module that supplies the energy for this is in the center the petals have a reflective coating on the outside, so that they mirror their surroundings when closed. 

There is another illusion. The blue of a flower, of satin, or of the sea, indeed the blue of any illuminated object, is but deception. The colour of a body lit by the Sun or an electric light is merely the colour of the radiation which it repels. The cornflower in the sunlight is anything but blue Its atoms swallow all the colours but regurgitate the blue. It might be called antiblue . This is... 

Orchids of the Mediterranean genus Ophrys and several Australian genera, including Cryptostylis and Caladenia, have converged upon a remarkable category of deception - pseudocopulation - because their flowers use odor, visual, and tactile cues to mimic female hymenoptera (reviews Staudamire, 1983 Borg-Karlson,... 

Lunau, K. (1992). Evolutionary aspects of perfume collection in male euglossine bees (Hymenoptera) and of nest deception in bee-pollinated flowers. Chemoecology 3 65-73. 

Evolutionary shifts from reward to deception in pollen flowers. In The Pollination of Flowers by Insects, ed. A. J. Richards, pp. 89-96. London Academic Press. 

Figure 22.1 Examples from two conceptual axes of interactions between flowers and their animal visitors. Axis 1 is a specialization-generalization spectrum of plant-pollinator interactions. Panel A depicts a guild of red Chilean flowers that share one species of hummingbird as a pollinator. In Panel D, a Perideridia umbel is visited by several families of bees, wasps and flies most are effective pollinators. Axis 2 describes relationships in which animals visit flowers for their own reproductive purposes. In panel B, a female Tegiticula moth gathers pollen from anthers of Yucca filamentosa, for which it is both obligate pollinator and seed predator. In panel C, a Drosophila fly (black arrow) is lured by appearance and smell of decaying matter to a deceptive Aristolochia flower, seen in cross-section. Floral scent plays diverse roles along these axes, including pollinator attraction in food- and sex-based mimicry. All photographs were taken by the author.

Ayasse M., Schiestl F. R, Paulus H. F., Lofstedt Hanson B. S., Ibarra F. and Francke W. (2000) Evolution of reproductive strategies in the sexually deceptive orchid Ophrys sphegodes how does flower-specific variation of odor signals influence reproductive success Evolution 54, 1995-2006. 

Liquid nitrogen is deceptively dangerous it looks like water, but at its extremely cold temperature (-195.8°C), liquid nitrogen can do extensive tissue damage. A common lab demonstration is to place a flower into a Dewar of liquid nitrogen, remove the flower, and hit, or crush, the flower with a blunt object. The previously soft flower shatters as if made of fine glass. A finger can shatter just as easily. 

Several orchids have remarkably characteristic pollination systems employing sexual deception in this system, the flowers mimic the visual, tactile, and olfactory traits of the females of particular hymenopteran species and so deceive conspecific males into attempting to mate with the flowers. In particular, the floral scent, which has a composition identical to that of female sex pheromones, is a key mediator of this exclusive and species-specific mode of pollination. 

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