Summoned by screams
THE botanical kingdom is rife with deceivers. Carrion flowers mimic the smell of rotten meat in order to attract scavenging beetles and flies and then cover them in pollen. Passion vines, beloved by some butterflies as food for their caterpillars, have yellow spots on their leaves that make them look as if they have already had an egg-laying visit from a gravid female. And numerous carnivorous plants lure insects with sweet odours, only to devour them. Now Stefan Dötterl and Annemarie Heiduk, of the Universities of Salzburg and Bayreuth respectively, think they have uncovered yet another form of deception. As they describe in Current Biology, a vegetable called the parachute plant uses chemical signals to trick carnivorous flies into believing the insects those flies prey on are lying wounded inside it.
At first sight parachute plants, which have cone-shaped flowers (see picture) decorated inside with needlelike inward-pointing hairs, look as though they might be carnivorous themselves. They are not, though they come close to it. Insects that enter a parachute-plant flower fall into…Continue reading
Source: Economist