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The Hemipterans aren't stuck up.
A new case of symbiosis was reported in The New Scientist (31 August, 1996). Botanists at the University of Cape Town, were carrying out investigations on the plant known as 'Roridula'. "It is a spectacular bushy plant up to 2 metres tall. It catches insects in its sticky leaves so effectively that local people used to hang them up in their houses as fly-catchers. It was identified as carnivorous by Charles Darwin more than 120 years ago, but since then its carnivorous credentials have been questioned because of its lack of digestive enzymes." They noticed that moving among the dead carcases were 'hemipterans', a sort of carnivorous sapsucker, unaffected by the sticky hairs on the plant. These bugs attacked any freshly caught prey and sucked out the juices after which they excreted urea onto the leaves. The urea provided that plant with the necessary enzymes and food absorption was made possible!!
Flower Power
Generally speaking, pollination is the transfer of pollen grains from the stamen (male) of one plant to the stigma (female) of another plant of the same species. Pollination is absolutely essential for the fertilization and production of seeds. This transfer of pollen can be achieved by both simple and complex means. Perhaps the simplest of methods is by the wind but other techniques, far from being simple, display such wonderful, intricate, precise, design features that one wonders how they could possibly have evolved by blind, chance processes. Let us consider just a few.
Good Vibrations
In southern Africa there grows a pink gentian which is pollinated by carpenter bees. The petals are spread wide and in the centre of the plant is a curving white style and three large stamens. Each stamen ends in a thick yellow anther which gives the appearance of being covered in pollen. This is not the case, for the pollen is not to be found on the outside of the anther but on the inside and the only way it can escape is through a tiny hole at the top and there is only one way of extracting it. When the bee arrives at the flower it is making a high pitched buzzing noise with its wings. Once it alights on an anther it continues to beat its wings but alters the frequency of the wing beat so that the note of the buzz falls to approximately middle C. This makes the anther vibrate, causing the pollen grains to spout out of the hole at the top in a yellow fountain. The bee then proceeds to gather up the pollen before heading off to another gentian to search for more pollen holding anthers. It can only know this by landing on the flower and causing the anthers to vibrate but as it does so, it transfers pollen onto the style and cross pollination takes place.
Head over Heels in Love
The hammer orchid grows in the dry grasslands of South Australia. The flower of the orchid resembles the body of the female of a particular type of wasp. These wasps are unusual in that they live in the soil and only the male can fly. In order to mate, the female must climb to the top of any tall plant stem where it releases a strong mating scent (a pheromone) and awaits the arrival of an amorous male. However, the male wasps always appear about two weeks earlier than the females. The flower of the orchid, to take full advantage of this two week gap, opens its flower at the same time that the male wasps appear and emits a chemical odour almost identical to the female wasps sex pheromone. Attracted to the orchid by the scent, the male attempts to mate with the female 'decoy'. Unfortunately for the male, his actions trigger the plant's 'spring loaded' mechanism to react with explosive force, violently catapulting the wasp into a half somersault through the air, eventually crashing head downwards into the flower. The wasp's back rubs against the orchid's stigma and two pollen sacs are glued onto the creature's back. The wasp visits other orchids where this traumatic experience is repeated and pollen from the wasp's back is transferred to the new orchid thus ensuring cross pollination!
Making a meal of it
Carnivorous plants usually grow in soils of an acid, boggy and
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