Many British orchids are named for their animal or humanoid appearance. List some and you have all the characters for a nursery-rhyme tale of transformation and trickery: lady,\u00a0frog, man, fly and spider. Today\u2019s protagonist is the fly orchid (Ophrys insectifera), a subtle conjuror of alternate realities and a plant I\u2019m fortunate to encounter yearly on my local South Downs hill. Favouring the dappled interface of chalk grassland and woods, it flowers here from mid-May. It\u2019s hard to spot amid the bugle, wild marjoram, agrimony and dock, but once I have my eye in, I find upwards of 20 plants.<\/p>\n
While they look like no fly I\u2019ve ever seen, the tiny blooms do have an uncannily insectile appearance. This is mostly down to a special petal, the labellum, which is minutely modified for luring in pollinators. Up close, I can see how its edges are curved back just so, a\u00a0sleight of folding which gives the illusion of volume. An iridescent blue patch at its centre suggests the\u00a0sheen of folded wings.<\/p>\n
Some orchid names say less about the plant than the human knack for seeing resemblances. The fly orchid, however, belongs to a genus, Ophrys, in which the likeness we perceive is also biologically significant. Thanks to their striking visuals and pheromone-mimicking scents, these plants seduce male insects into attempting sex with them, then stick pollen to their heads. Yet while most Ophrys species are bee-pollinated, the fly orchid is pollinated by a wasp \u2013 the digger wasp. This is highly unusual, and suggests that it emerged early in the evolutionary history of the genus, before bees took over pollination duties, driving rapid diversification\u00a0in the group.<\/p>\n
Sadly, I\u2019ve never seen a wasp go near one of these plants \u2013 they have an alarmingly low rate of fertilisation. This puzzled Charles Darwin, who spent years studying a population in Kent and also never saw one pollinated. \u201cIt is remarkable \u2026 that this Ophrys has not been rendered more attractive to insects,\u201d he wrote<\/a>. It wasn\u2019t until the 1910s that the pollination mechanism was widely recognised. Nowadays, philosophers and naturalists debate the ethics of the exchange. Does the flower exploit the bee, duping it into a waste of sexual energy? Or does the bee take some pleasure, ensuring a\u00a0happy ending for both parties?<\/p>\n