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The Ark Files - Come Hither
Mimicry, bribery and thuggery are just
some of the tricks that flowers resort to
in order to attract the insects they need
to pollinate them.
Orchid imposters
 Orchids are, perhaps, the cleverest and most well known impersonators. One particular orchid looks really like a female wasp complete with eyes, antennae and wings. It even gives off the smell of a female wasp when she is ready to mate. Easily fooled male wasps attempt to mate with the orchid, depositing a load of pollen within the flower and immediately receiving a fresh batch to carry to the next false female.
Nights in white satin
It's not only during the day that insects buzz around
making themselves useful. Some flowers, such as night blooming
cacti, only open after the sun has gone down,
and so they rely on moths that are only active at dusk
and during the night to pollinate them. To attract these
nocturnal insects in the dark, the flowers are large and
mostly white or very pale, with a heavy fragrance to help
guide the moths towards them.
Not everyone's perfume
 We expect flowers to smell lovely, or at the worst to have no scent at all.
There is one flower, however, which really stinks. Rafflesia lives in the jungles
of Sumatra and is the largest flower in the world - it's a metre wide. This huge
flower spreads its leathery, wart-covered petals just above the surface of the
forest floor. In the centre is a vast, spike-filled cup from which comes the
putrid stench of rotting, dead flesh. So what could possibly be persuaded
to approach this monstrous flower? Flies that feed on decomposing
bodies swarm to it, expecting a feast, and happily transfer pollen as
they come and go.
For some blooms it is not enough to just smell like a dead animal.
The South African Starflower has petals that are brown and wrinkled
and covered in hairs so that it even looks like the decaying skin of a
carcass. To complete the picture, the flower produces heat to mimic
the warmth given off by decomposing flesh. The Starflower is so
convincing that the flies that visit it also lay their eggs there, expecting
the hatched maggots to feed on the rotting meat. The maggots die from
starvation but the plant is fertilised.
Guerilla tactics
 Some flowers have become obstacle courses, ensuring
that their insect visitors, eager for nectar, are "attacked" by
stamens and pressure-hosed with pollen before they are able
to leave. When a bee lands on a Broom flower, the stamens,
which are hidden in a sealed capsule of petals, shoot out and
strike the bee, covering its furry abdomen with pollen.
Need to be over 18
 The Bucket Orchid from Central America makes a nectar
so potent that it overwhelms its visitors. Bees that innocently
climb into the flower's slippery "throat" have only to take
a small sip before they begin to stagger about in a very
drunken manner. The bees soon lose their grip and slip down
the orchid - straight into a small pool of liquid. The only
way out of this is up a spout. As the sloshed bee wobbles
upwards, it has to wriggle beneath an overhanging rod which
showers it with the orchid's pollen.
Gotcha!
 Another orchid, the
marsh Epipactis, uses
its large lower petal as
a trap. At the base of the
petal is a cup filled with
nectar - the insect's reward.
The rest of the petal forms
a sort of landing stage. As
the insect lands on this
runway its weight lowers the
petal, allowing it to get into
the now open cup of nectar.
But the runway is elastic and
instantly springs up, trapping the
insect inside. The insect must then
back out through the only available exit,
which forces it to brush against the orchid's
pollen masses
as it escapes.
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