Orchids have developed highly specialized pollination systems and therefore the chances of being pollinated are often scarce. This is why the orchid flowers often remain open for very long periods and why most orchids deliver pollen in a single mass, every moment of pollination is successful thousands of eggs can be fertilized. Pollinators are often visually attracted by the shape and colors of the lip. The flowers can produce attractive scents. Although absent in most species, the nectar can be produced in a ram (8) of the lip, on the tip of the sepals or septa of the ovary, the typical position between the Asparagales.
In the orchids that produce pollinia, pollination happens as a variant of the next. When the pollinator enters the flower, touches a viscidium, which quickly adheres to its body, usually on the head or abdomen. Leaving the flower, pulling pollinium of the anther, as it is connected with the caudicle viscidium or stipe. The caudicle then folds and polynya moves forward and down. When the pollinator enters another flower of the same species, pollinium has taken a position that adhere to the stigma of the flower in second, just below the rostellum, to pollinate it. Holders of orchids may be able to replicate the process with a pencil, a small brush or similar device.
Some orchids mainly or entirely based on self-pollination, especially in colder regions where pollinators are particularly rare. The caudicles can dry if the flower has not been visited by any of pollinators and pollination then fall directly on the stigma. Otherwise the anther can be rotated and then enter the cavity of the stigma of the flower (as in Holcoglossum amesianum).
A study published in the scientific journal Nature has hypothesized that the origin of orchids goes back much longer than originally expected. An extinct species of stingless bees, Dominican Proplebeia, was found trapped in amber from the Miocene of last 15-20 million years. The bee was carrying pollen from one orchid taxon unknown Meliorchis caribaea in its wings. This finding is the first orchid fossil evidence to date.