Information Processing in Bacteria and Plants

Bacteria

Source: Stefan Mosebach (used with permission from the artist)

We introduced the notion of “informavore,” or a consumer of information, in our previous post. We’d now like to introduce a distinction to provide more nuance to this notion, which we’ll explore in this and future posts. Our goal for now is to clarify how there is a substantial difference between the mechanical transmission of information and the meaningful usage of information by informavores (even though the boundary between information-mechanism and informavore is fuzzy). We first focus on the simplest kind of information users there are in the animal kingdom: bacteria. We’ll also show that there are strong theoretical considerations to include plants as a substantial addition to the already extensive list of informavores.

The distinction between the simplest kind of informavore and the most sophisticated kinds of information machines is not based on a dichotomous understanding between full conceptual cognition (or rationality) and a strictly causal mechanical manipulation of information. We need an easy way of distinguishing simple informavores from machines—we want to identify the edge of this boundary, as it were. But using full human cognition to draw the boundary would simplify things at the high cost of deeply distorting where the real boundary lines are. Not all cognition is human cognition or, at the very least, humans are not the only informavores, even if they are the most insatiable ones. So a less human-centered approach is needed here.

Bacteria are simple organisms that can be drawn toward light and can consume a variety of other organisms (usually what we would consider “waste”). If bacteria count as informavores, we might be approaching the boundaries of the simplest kind of informavore by analyzing in what sense unicellular organisms are consumers of information. But at the same time, if bacteria are going to count as informavores, the chasm between bacteria and rational human cognition must also be explained, since not all informavores are the same. A possibility here is to understand bacterial cognition as a kind of agency without full cognition. According to this proposal, bacteria are goal-oriented informavores who adapt to situations, learn from their environment, and interact with what their environment affords to them—they count as perfectly competent informavores.

Fermín Fulda (2017) argues for this view and explains that it has the advantage of avoiding the dilemma of considering bacteria as either full-blown cognizers (like humans) or mere machines. It also has the advantage of offering a spectrum of cognitive agency and a spectrum of informavores, which could also be understood in terms of various types of attention (Haladjian and Montemayor, 2015). The issue of whether bacteria are conscious must be settled independently of whether or not they count as informavores—not all informavores must be conscious, even if they pay attention to what their environment presents them (see Montemayor and Haladjian, 2015). So in agreement with Fulda, we believe bacteria are legitimate informavores rather than mere transmitters of information, even if they lack the type of cognition characteristic of human rationality. The important point is that agency (being oriented toward goals that agents must be capable of meeting based on their selective and trust-worthy capacities) defines the boundary between mere machine and informavores.

But we can go further and explore the possibility that an entire kingdom that is typically relegated as essentially “mechanical” might teem with informavores: the plant kingdom. Carrie Figdor’s fascinating new book Pieces of Mind (Figdor, 2018) opens this theoretical possibility. Literalism, the view Figdor defends, holds that statements like “plants make decisions” or “bacteria communicate linguistically” should be interpreted literally. That is, across human and non-human domains, we mean the same things with these statements or predicates, which are frequently and quite seriously used by scientists who specialize in studying non-human behavior. Pieces of Mind is an admirable and thought-provoking defense of this claim, providing arguments against human-centered interpretations of scientific statements.

This point about extending the set of informavores to include plants, based on Figdor’s work, is a subtle one. Figdor is not claiming that plants think and cognize. Rather, her main claim is that scientists think they could; that is, the sentences scientists use to describe their cognition or communication capacities should be taken literally—as something that could be true or false. This means that the list of informavores should be enlarged to investigate this possibility, and, if this hypothesis is confirmed, this list could get very big indeed. A whole field on plant cognition is emerging, and we could soon witness more discussions on this topic (see Segundo-Ortin and Calvo, 2019). Figdor is challenging any framework that is based on human cognition as the sole standard for comparison, and so her approach seems to be the correct framework for interpreting the evolution of attention and cognition in general.

So while the most obvious informavores are humans, with our insatiable appetite for a diverse diet of information, the term informavore can also include simple unicellular organisms and plants, with all the complexity and diversity they present. In future posts, we will explore a spectrum of other informavores, highlighting their commonalities and differences.