What are the tricks used by orchids to atract insects ?
The tricks used by the orchids to attract insects are of sexual nature and they consist in producing flowers which looks like a female insect or even smell like the female, in this way, males being attracted by the fake females, waiting to mate with them. This behavior is well-known as "sexual deception". The deceived insects are usually bees or wasps males, which abandon the fake female, and go to another one, with their bodies covered by pollen.
Because of the misleading appearances, the orchid looking like a female wasp or female bee, can attract only male wasp or bee, and no ants, flies or other insects. This thing could be possible if the behavior of attracting the prey would be food deception, when the flower smells or look like the wanted food.
This kind of behavior is good for selection, because of the higher amounts of pollen transported from one orchid to another orchid from the same species. At the species with a large number of pollinators, this efficiency is decreased all at once with the quantity of pollen fallen on the ground or put into another species.
In addition to the usual mechanisms- color, fragrance, food, that is nectar - by which flowers attract insects, orchids deceive insects into carrying pollen from one plant to another.
The insects are often easily fooled by orchids which look and also smell like they might contain nectar but they don't contain any nectar.
Some orchids produce globular growths which resemble the female genitals of insects and to complete the deception produce molecules that mimic the pheromone scent of the female insect. Once the deceived male insect lands on the orchid some of them even close their petals and the insect in order to escape has to squeeze past the sticky pollen bundle. Usually each species of orchid mimics only one specific pheromone of one local insect to ensure that the pollen from one plant reaches another orchid of the same species. Thus the danger of inter pollination is avoided.
Orchids are a beautiful flower that requires the use of a false attraction pheromone in order to trick insects allowing for fertilization of the plant to occur. Many of the different varieties mimic the pheromones of other insects inviting the insect to pollinate the plant. However, once at the plant site, the insect is tricked because it leaves without the benefit of having gained any pollen or nectar. For example; In order to attract hornets for pollination, the orchid gives off the alarm pheromone of a honey bee. The hornet senses the alarm pheromone and goes to the orchid ready to attack the honey bee, its prey. There are some orchids which attract other insects, so that upon receiving a reward of a chemical released by the orchid the insect itself gives off a pheromone that attracts other insects necessary for the pollination of the orchid. Orchids also use color to attract birds and insects.