It turns out plants can think – but should they have legal rights, too?

The Light Eaters Zoe Schlanger 4th Estate €22

As a child I remember being terrified just by the cover of John Wyndham’s The

Day Of The Triffids. The scifi horror tale of killer plants left me suspicious of even the office pot plant. But the book seemed stuck in fantasy until I read Zoe Schlanger’s The

Light Eaters.

According to this book, we need to rethink plants – they may be able to see, communicate, recognise and protect their siblings. And if they are not fully conscious, could they at least be termed aware?

Zoe Schlanger was originally a climate reporter whose beat was (as she put it) all about ‘disease, disaster and decline’. Looking for something to uplift her, she started to research plants.

And I’m so glad she did. It’s rare that you read a book that makes you want to grab people to tell them what it’s about, but this is one of them. While she is clear that there is still much that isn’t fully understood about this part of life, what she does write about is enthralling. I had no idea for example that not only do male ferns have sperm that swim in water looking for fern eggs to fertilise, but that they also emit a hormone that causes the sperm of neighbouring fern species to slow down – basically sabotaging their rivals’ chance of survival.

Or that a leaf, sensing it has been nibbled, can produce a plume of airborne chemicals that tell other branches to activate chemicals to repel aphids or other plant-eating bugs. Plants also seem to have a memory – nasa poissoniana a flowering nettle, remembers the time intervals between bee visits to pollinate them, and can anticipate the next time the pollinator will arrive, and have the nectar and pollen ready.

And the garden flower impatiens can recognise its kin. If planted next to sibling plants, it politely arranges its leaves to avoiding shading them. Schlanger debates whether plants should even have legal rights. After all, non-human entities like trusts and ships have these rights, and given none of us would be here without the plants to create the oxygen we need to survive, could this be the future? You might look at that pot plant in the office that you’ve neglected to water in another light now.