Fungi are talking to each other.
OK, maybe I'm exaggerating a little. But, like, a little, and maybe even not at all. Fungi are, possibly quite literally, talking to each other, using neuronal-like interfaces. In other words, they're acting like the neurons of your brain, but for entire communities and ecosystems, and with signals closely resembling human speech.
Let me explain.
For a while, it has been known that fungal mycelia - the underground, spiderweb-like bodies of fungi - produce spikes of electricity. In fact, many organisms other than vertebrates do this, if often chemically. But what these spikes were, or what they might mean in fungi, was not known - until now.
Andrew Adamatzky, a computer scientist, knew about these electrical spikes in fungi and wondered if there was anything special to them. So he stuck some electrodes, or probes that detect electricity, into substrate colonized by mycelia or directly into the fungi themselves. He studied 4 species: Omphalotus nidiformis (ghost fungus), Flammulina velutipes (Enoki fungus), Schizophyllum commune (split-gill fungus), and Cordyceps militaris (caterpillar fungus). He measured various qualities of the electrical spikes the fungi generated and compared them for differences and similarities between species. Assuming the electrical signals carried information, he then compared them with human language to see if there was any similarity. There was astonishing similarity.
Figure 1: From article: Photographs of pairs of differential electrodes inserted in (a) C. militaris, the block of a substrate colonized by the fungi was removed from the plastic container to make a photo after the experiments, (b) S. commune, the twig with the fungi was removed from the humid plastic container to make a photo after the experiment, (c) F. velutipes, the container was kept sealed and electrodes pierced through the lid.
He compared the signals to several languages, including English and Russian, whose average word lengths were comparable to the average word lengths of the fungi. S. commune had the longest average word length. The electrical spikes, or "words", often appeared in "trains" of spikes, which were similar to sentences. The "words" and "sentences" were measured as number of electrical spikes, interval between spikes (in minutes), and amplitude (wave height on a graph) of spikes. Some species also showed more diversity in their spikes than others.
Not only were these fungal "languages" similar to the European languages with which they were compared, they exceeded those languages in complexity. Then again, cellular signaling pathways are about as complex as incomprehensible (for those who haven't studied them, anyway). But the key difference here is the nature of the signals, which more closely resemble signals between neurons in the vertebrate brain than direct cause-effect relationships. And if we consider inter- and intra-species communication, we may be on to something.
Figure 2: Various ciliates. Ciliates of different species communicate via intra- and inter-cellular pathways, if mostly for self-propagation.
Figure 3: Ants engage in complex communication with each other and with other species who can understand them. Considering the complexity of ant societies, ant colonies may be organisms unto themselves.
Credit: Retro Lenses, Wikimedia Commons, CC-BY 4.0.
Figure 4: Bees engage in complex signal communication, using their movements of their abdomens to indicate to other members of the hive where food and resources are. The most well-known communication system is the waggle dance, shown here (waggle dance - doesn't that sound cute?).
Credit: Figure design: J. Tautz and M. Kleinhenz, Beegroup Würzburg - derivative work: Anaxibia. Wikimedia Commons, CC-BY-SA 2.5.
Figure 5: Plants communicate in myriad ways, including sign-mediated communication, chemical signals, and mycorhizzal networks. Adamatzky cites the recent movement toward using the conceptualization of plant communication as language as a way to de-objectify plants as living, valuable beings and not just useful objects (a paradigm we should definitely adopt!)
Credit: Public domain.
Take the fungi in Adamatzky's article, for example. Mycorhizzal fungi are already known to form symbiotic relationships with trees and other plants through which nutrients, resources, and possibly information are exchanged. Although Adamatzky's fungi are not mycorhizzal, the fact that they produce complex signals possibly carrying information may indicate that other types of fungi do as well. Since mycorhizzal networks cover entire landscapes and ecosystems, this could have big implications. And if similar information is being transferred between vastly different organisms across great distances - we might have a brain in our hands.
Granted, it's a stretch. We can't jump to conclusions, and a healthy dose of skepticism is good for research. After all, Adamatzky's fungal electricity may carry no information at all. But at the same time, we must be open-minded. Dismissing evidence and possibilities just because they "sound ridiculous/impossible" is also a bad move for progress.
After all, we already know that Terra is a living organism. Could she be conscious as well?