Venus flytrap

Killer plants

A thousand tiny dewdrops glitter in the cold morning sun. In the moist, green undergrowth, concealed among the moss and the grasses, the predator lies in wait for its prey. A fly, hovering above in the chilly air - drawn perhaps by the sickly smell, or by the glistening beads. Not until the hapless insect is firmly stuck does it realise its mistake. As legs and antennae flail for freedom, each one in turn becomes bound to a sticky drop. The whirring wings are smothered, glued like paper. There can now be no escape.

Underneath, its captor stirs. Gracefully, it wraps its prey, embalming it in a sarcophagus of sticky threads. Eventually the fly's struggling comes to an end. With the meal safely rolled up inside one of its long green leaves, the sundew begins to digest its victim.

None of the snarling, swooping, snatching hunters of the animal kingdom could match the finesse of this killer. No padded feet could move so silently, no jaws could hold so firmly, no surprise attack could be executed with such effortlessness. Animals ambush their victims in the shadows, or stalk them in the night. Carnivorous plants, in contrast, are not ashamed of their habit. There are few things in nature more wonderfully blatant than the gaping, spiked jaws of a Venus' flytrap. Or the beautifully ornamented cups of the tropical pitcher plants, who dangle their decorated stomachs from the ends of their leaves. These plants are predators, and they are proud of it.

Nature, red - but not in tooth and claw. Just pure, seductive glamour. Carnivorous plants adorn themselves with shining jewels, sweet perfumes, and majestic hoods of purple and crimson. Their names tell it all. Trumpet pitchers stand tall and tubular, announcing their presence with a fanfare of deep colour. The rainbow plant sparkles in the riches of its murderous lifestyle. The forked-tongued cobra lily poses like a snake as it prepares to strike. Yet here there is no hissing and spitting, no quivering animal fear, no poison bite. This cobra is perfectly still, perfectly silent - and lethal. Underneath the veined hood, no fangs protrude from the lily's scarlet jaws. The predator sways in the sunshine: there will be no stab in the back, no shriek in the darkness. It is Dracula by daylight.

The plants have good reason for showing off their ill-gotten wealth. The blood red lips, dripping in succulent nectar, are enticing and entrapping. Insects, blinded by the sensual thrills of sweetness and scent, wander helplessly past the glittering jaws and into the dripping green depths beyond. Few will ever see sunlight again.

Digestion, like everything else, is accomplished with a horrible cleanliness and efficiency. Plants do not chew or crunch, gnaw or grind - they simply dissolve their victims. It takes only a few days to reduce an insect to a dry husk, which is crushed into the depths of the plant, or else discarded on the wind.

Not all carnivorous plants are quite so passive. When some small aquatic creature brushes against one of the submerged capsules of a bladderwort, the plant's reaction is too fast for the human eye to see. With a silent gulp of water, the animal is sucked in, and entombed in the digestive interior. Back on land, many different varieties of plant possess leaves that can fold or roll to ensnare their defenceless prey. There is more than mere motion going on here. In the electrical impulses that race through a closing flytrap we see a distant shadow of a very animal feature, one particularly precious to our own species - a nervous system.

It is all too easy to forget, when we look at these magnificent plants, that their ingenuity and cunning is an illusion. Their intricate traps and lures are really nothing more than sophisticated leaves, carved and contorted by millions of years of natural selection. Underneath the vicious power and sensual glory, carnivorous plants are nothing more than the finely-crafted tools of an evolutionary sculptor.

Yet there remains something deeply disturbing about the very concept of a carnivorous plant. Perhaps they remind us that, in a deep biological way, humans and plants have more in common than we would like to think. Across long-forgotten aeons of Darwinian history, plants are our distant relatives. In a way, we are variations on the same design. And we share the same brutal purpose.



© Andrew Gray, 2002