7.9 Helping Each Other

A 1997 article in Nature reported a discovery that changed our understanding of plant-fungus relationships. We already knew that most plants form symbiosis with soil fungi — called mycorrhizae — exchanging nutrients beneficial to both.

But fungal filaments (hyphae) can connect multiple plant species, forming a potential network.

This research demonstrated such a network in nature: radioactive tracers moved from birch (Betula papyrifera) to Douglas fir (Pseudotsuga menziesii) — and vice versa. The flow direction depended on season or plant health. Non-compatible plants did not receive anything — confirming the exchange occurred through the fungal network.

So — do plants help each other through fungi?

Is this extraordinary behaviour evidence of intelligence — or an automatic biochemical mechanism?

From this study came a bold idea: perhaps entire forests are connected through fungal networks — a huge living web nicknamed the Wood Wide Web.

The idea captured media and public imagination, especially because it seemed to reveal altruism among trees. But current research shows exchanges only between certain connected plants — and the idea of a universal cooperative network remains debated and unproven.

And we must not forget: nature is not only cooperation — it is also competition: between plants, fungi, bacteria, and more.

Even bacteria — the simplest living organisms — can sense their environment through membrane receptors, process information, and act accordingly.

Can we call them intelligent?