Is camouflage a form of communication?

Tokyo, Japan – A researcher from Tokyo Metropolitan University has proposed a new interpretation of camouflage in nature. Most theories dismiss it as a form of communication, since there is no apparent “signal,” but rather a lack of one. Here, in an information-theoretic approach, it is shown that camouflage can be framed as an “information-masking” signal, one which disrupts the flow of information. The same idea might be applied to the wider field of communication, where signals may be present which proactively do not convey information.

Camouflage is a ubiquitous part of the natural world, from octopuses to chameleons, where creatures adopt colors and behaviors that help them blend into the background. This can help them avoid detection from predators or even be an essential hunting strategy. A conventional understanding of camouflage would suggest that there is not much to connect camouflage to communication. After all, it is all about adopting states which do not convey anything to other creatures.

In a challenge to orthodoxy in the subject, Assistant Professor Minato Asari from Tokyo Metropolitan University proposes that this is not the case. Existing definitions of what constitutes a “signal” for communication suggest that it needs to be detected by other creatures and modify their behavior; since camouflage is used to avoid detection, this disqualifies it as a signal. In a departure from this framework, the new research suggests that a closer investigation of detection is required. The key idea is that other creatures do, in fact, detect the camouflaged animal, but as a signal which it chooses to ignore or treat as something else. Existing theories which suggest that camouflage is the absence of a signal may be overly simplistic.

Recent experiments cited in the work support this view. For example, a group of chickens was given some exposure to twigs, while others were not. When they were given caterpillars which camouflage themselves as twigs, the group which had prior exposure to twigs took significantly longer to attack the caterpillars. Thus, the act of ignoring them is a learned behavior; the act of camouflage is therefore modifying the behavior of predators, qualifying it as a signal.

This changes how the problem of communication is treated from the perspective of information theory. On top of an information-transmitting signal, there is also an information-masking signal. This is distinct from deception or misinformation; while deception is all about sending a signal which contains the wrong information, camouflage is about ensuring that the true information remains concealed.

While Dr. Asari’s work has been presented to study camouflage, he proposes that the concept of an information-masking signal can be adopted into the wider study of communication. This extends beyond animal signaling to how information theory can be applied when information is being both transmitted and masked.

This work was supported by the Suntory Foundation’s “Grant for Groundbreaking Young Researchers” and JSPS KAKENHI Grant Number 25K21835.