It may not be the most attractive orchid on the planet - at least to our eyes. Yet the Fly Orchid (Ophrys insectifera) has come up with an ingenious way to ensure that it is pollinated. Its flowers look like flies and its scent mimics sexual pheromones. This combination attract hordes of male insects, themselves simply attempting to ensure the continuation of their species. These unwitting insects are enticed in to performing the act of reproduction - on a flower. The fly orchid is the agent provocateur of the plant world.
The bees, flies and other insects attracted to this powerful combination of lures may not get quite what they had anticipated and they do not even get a sustaining supply of nectar, the sugar-rich liquid produced by plants. We might like to think that we wouldn’t be as easily fooled but if you are an insect the heady mix of what appears to be an attractive mate coupled with the allure of the scent is more than it can resist.
This simple but effective ploy has made the Fly Orchid – geographically speaking at least – a very successful species. It can be found from the fields of Ireland to the mountains of Spain to the east. Its habitat stretches as far as Romania and Ukraine. It has even been found in Norway and this makes it the most northern of the ophrys genus of orchids.
The Fly Orchid stays dormant underground until the late summer and then, when its bulbous tubers are almost depleted as a food reserve, it grows a rosette of leaves. While this is happening a new tuber begins to grow, ready for the following year. As the flower blooms the leaves begin to wilt, which makes the appearance of the flower as insect stand out even more.
They system by which the fly orchid attracts insects is known as sexual deception. Once the visual and tactile clues, together with the pheromone perform their trick and an aroused insect lands on the flower it attempts to mate with it – with, of course, no success whatsoever. Yet it is this pseudocopulation which enables pollen to become attached to usually the abdomen or head of the unwitting pollinator.
Once the jilted insect realizes that it is not actually mating with a female of its species it flies off – and is promptly enticed in to another act of pseudocopulation by a nearby fly orchid. Yet an insect will only be duped a certain number of times. Once it has determined that it has been tricked a few times it will not try its luck with any of the flowers in the vicinity again.
Insects are cleverer than many might imagine and only about ten percent of a fly orchid population will get pollinated. Yet that is not the end of the world for the fly orchid by any means – the deception has already worked, if only for one in ten of the flowers. The fly orchid has a final trick up its sleeve.
Each pollinated orchid will produce over ten thousand minuscule seeds. This is more than enough to both preserve and propagate the species. The next generation of orchids is ensured and will, in its turn, find plenty of willing dupes to deceive – at least for as long as it needs to start the cycle all over again.