Where the Wood-Wide Web Went Wrong

Where the Wood-Wide Web Went Wrong
undark.org

This is because of Bayesian priors. To be interesting enough to be featured in mainstream media, it needs to be surprising or unexpected in some way. However, that means that the Bayesian prior probability is low, and thus, especially since p = 0.05 is used for publication regardless of how unexpected the result is, the conditional probability is lower compared to a study that was not featured in media (because it was not a surprising result - meaning that the prior probability was higher).

One of us (Jones) was involved in the first major field study on CMNs, published more than 25 years ago. That study found evidence of net carbon transfer between seedlings of two different species, and it posited that most of the carbon was transported through CMNs, while downplaying other possible explanations. This is what’s known as “confirmation bias,” and it is an easy trap to fall into. As hard as it is to admit, it was only due to our skepticism of the recent extraordinary claims about the wood-wide web that we looked back and saw the bias in our own work.

Over decades, these and other distortions have propagated in the academic literature on CMNs, steering the scientific discourse further and further away from reality, similar to a game of “telephone.” In our review, we found that the results of older, influential field studies of CMNs have been increasingly misrepresented by the newer papers that cite them. Among peer reviewed papers published in 2022, fewer than half the statements made about the original field studies could be considered accurate. A 2009 study that used genetic techniques to map the distribution of mycorrhizal fungi, for instance, is now frequently cited as evidence that trees transfer nutrients to one another through CMNs — even though that study did not actually investigate nutrient transfer. In addition, alternative hypotheses provided by the original authors were typically not mentioned in the newer studies.

As these biases have spilled over into the media, the narrative has caught fire. And no wonder: If scientists themselves could be seduced by potentially sensational findings, it is not surprising that the media could too.