I talk to the trees - and they answer me

Click to follow
PLANTS beg for water, count and have a memory - but are they intelligent?

Malcolm Wilkins, Regius Professor of Botany at Glasgow University, demonstrated to the British Association yesterday that plants can talk and hear, have a sense of touch and taste, and can detect gravity.

'In fact, plants can do almost everything animals can do except walk about,' Professor Wilkins said. 'We've got two eyes which are both the same . . . plants also have two eyes, but they are different.' One sees red, the other blue. Plants will bend towards light, but only if their blue eye picks up blue light. Seeds germinate, but only if exposed to red light.

Seeds will grow stems upwards and roots downwards, regardless of which way up they land on soil. They appear to do this using a gravity detector in their roots consisting of tiny cells with bags of starch granules inside, which roll around as the root tips up.

Plants can count, Professor Wilkins said, using the Venus fly trap to prove it. The plant has three sensory hairs. If a fly touches one of them, the plant ignores it. If it touches two, its cage-like leaves slam shut. This shows the plant can count to two - recognising 0, 1 and 2. 'The most powerful computers in the world are based on a system that can only count to one,' he said. Moreover, the plant will close only if it is touched twice in 30 seconds, showing it has a memory.

Plants can also talk, he said, although in voices too quiet for people to hear. Tiny amplifying microphones can pick up the persistent clicks of collapsing water channels of plants that are desperate for a drink. This research is being used by Californian wine producers who have linked the microphones to an automatic irrigation system that waters the vines when they cry out.

New techniques of biotechnology are producing sophisticated plant forms. One, which involves firing genetic material from other species into plant cells, has already come up with what Professor Wilkins suggested might be a smoker's favourite - a self-lighting tobacco plant given genes from a firefly which make it glow in the dark.

Plant intelligence remains elusive, Professor Wilkins concluded. 'I don't think there's any evidence at all that plants are intelligent. They are pre-programmed zombies . . . but certainly a great deal more interesting and sophisticated than most people realise,' he said.