7.1 Is intelligence possible without a single neuron?

Do you really need a brain to be intelligent?

We saw that neurons and the brain are at the foundation of how we usually think about intelligence — and that many brains working together can lead to extraordinary results.

But what can we say about all those living beings that perform remarkable behaviours and yet don’t have a single neuron — let alone a brain?

We’re talking about fungi, bacteria, protists and, of course, plants.

To attempt an answer, we need to reflect on the definition of intelligence we are using — and continue the investigation. In this case file you’ll explore some of the most emblematic scientific discoveries in this field. You’ll find their original publications, but to read them you’ll need a classic scientific tool: a magnifying glass.

You’ll notice it’s natural for us to interpret these findings in anthropomorphic terms.

But what happens if we try — as much as possible — to describe them objectively instead?