Plants dominate every terrestrial environment, composing ninety-nine per cent of the biomass on earth. By comparison, humans and all the other animals are, in the words of one plant neurobiologist, “just traces.”
The New Yorker December 23, 2013 Issue.
Plants are an integral part of life. They are so important to our survival that their disappearance from Earth would be catastrophic to the existence of animals and humans. Of course they are not going to vanish from our planet anytime soon, but when a book comes out to advocate their rights (yes, you heard right) and to support their intelligence, it may be time to ask ourselves: Do we really understand plants?
Are plants intelligent? Can they solve problems, communicate, and navigate their surroundings? Or are they just passive living organisms that are incapable of independent action or social behavior? These are the questions that are thoroughly tackled in a compelling new book titled Brilliant Green: the Surprising History and Science of Plant Intelligence. Written by plant neurobiologist Stefano Mancuso and journalist Alessandra Viola, the book explores the awareness and intelligence of plants in a refreshing and convincing manner.
Mancuso claims that intelligence is the ability to solve problems, and plants are incredibly good at solving their problems. However, unlike humans and animals, plants don’t have a brain. How can they solve problems, act intelligently, or respond to stimuli without a brain? In fact Charles Darwin (who studied plants extensively for decades) was one of the earliest scientists to talk about the intelligence of plants. He noted that the radicle (root tip) is “endowed with sensitivity and having the power of directing the movements of the adjoining parts, acts like the brain of one of the lower animals.”*
The radical is the key
In his book Mancuso also cites evidence that the key to plant intelligence is in the radicle. Mancuso and his team recorded the same signals given off from this part of the plant as those from neurons in the animal brain. However, instead of having just one root, most plants have millions of individual roots, each with a single radicle. So, instead of a single powerful brain, Mancuso argues that plants have a million tiny computing structures that interact in a complex network, similar to the Internet.
Mancuso also explains how plants operate intelligently in order to find energy, reproduce, and ward off predators. For example, to meet their energy needs, plants tend to turn towards the Sun and many plants turn their leaves during the day to capture the most Sun. Other plants, such as the Venus flytrap, take a different route for energy by preying on animals. There are at least another 600 species of animal-eating plants. For plants to do this they have evolved complex strategies that enables them to catch and eat their prey. In addition, plants use animals in order to reproduce, which often involves crafty tricks and bait to attract pollinators.
There is even new research that says some plants go so far as to distinguish between the different pollinators and only germinate their pollen for the best. Many plants will even warn other species when danger is near. Plants also have evolved an impressive range of toxic compounds to ward off predators. There are even behaviors in plants that we would not expect, such as those similar to sleeping and playing, accordingly to the book.
In the book Mancuso goes on to argue that the state of plant conservation and the increasing evidence that plants are sentient beings should make people consider plants’ rights. After all, we depend on plants, which means that plant conservation is vital for human conservation. Evidence shows us that plants have plenty to teach us, and if we try to understand them more and appreciate how they function, we will certainly learn a great deal.
*Quoted from The Power of Movement in Plants by Charles and Francis Darwin