Organisms without brains may still exhibit intelligent behavior. This hypothesis was explored by Japanese researchers who investigated the decision-making abilities of fungi, specifically their spatial navigation.
They discovered that wood-decomposing fungi respond to varying configurations of wooden blocks, indicating that these fungi can discern shapes and possess problem-solving capabilities.
Works like neural connections in the brain
“You would be astonished by the capabilities of fungi,” states Yu Fukasawa, a microbiologist ecologist at Tohoku University. “They possess memory, the ability to learn, and decision-making skills. Truly, their problem-solving methods are astonishingly different from humans.”
Mushrooms proliferate by dispersing spores that develop into extensive, thread-like structures beneath the soil, known as mycelium. While we typically observe only the small mushrooms, with their stems and caps above ground, an immense network of interconnected mycelium lies beneath.
This subterranean network functions similarly to the brain’s neural connections, enabling fungi to gather and disseminate information about their environment.
Circle or cross?
Researchers from Tohoku University and Nagaoka College embarked on a study to understand the decision-making capabilities of wood-decomposing fungi, specifically their reactions to different geometric arrangements of wooden blocks. They arranged the blocks in two patterns: a circle and a cross.
Had the fungi been indifferent to these configurations, they would have grown evenly from a central point, without regard to the blocks’ placement. Yet, the observations indicated a more sophisticated behavior.
The team noticed that with the blocks arranged in a cross shape, the mycelium extended towards the four most distant blocks. The experiment’s authors proposed that these blocks acted as “outposts” for the fungi, prompting them to forge more robust connections to venture into new areas and access future nutrient sources. This approach enabled them to maximize their network expansion and nutrient intake.
As the blocks were positioned in a circular formation, the fungi distributed themselves uniformly across all the blocks, avoiding the circle’s center. The researchers deduced that the fungi found no benefit in focusing their growth within a densely populated region, opting instead to expand into other areas with potential food sources.
And they even talk!
According to the authors of the study, fungi not only gather environmental information but also adapt their growth strategies accordingly. The mycelium network appears to operate as a unified system, making growth decisions based on environmental analysis.
Fukasawa highlighted our limited understanding of fungi compared to plants and animals, noting that the study illuminates the covert intelligence of these organisms and their impact on broader ecosystems.
The rationale behind Japanese scientists attributing signs of intelligence to fungi is not fully transparent. Observing a sunflower track the sun or a vine’s tendril wrap around a support doesn’t typically evoke notions of intelligence.
This isn’t the first instance of this Japanese research team anthropomorphizing mushrooms. They previously claimed that mushrooms communicate post-rainfall via subterranean electrical signals, akin to conversation.
Electrodes were placed on six “two-colored lacquer” mushrooms by the scientists, who then tracked their electrical activity for days. Post-rainfall, the mushrooms exhibited increased activity, which the researchers interpret as communicative signals.
While it’s widely acknowledged that our knowledge of fungi is incomplete, these researchers are pushing boundaries by urging a reevaluation of intelligence in the natural world, questioning its origins and limits.