A systems approach to animal communication

Abstract

Why animal communication displays are so complex and how they have evolved are active foci of research with a long and rich history. Progress towards an evolutionary analysis of signal complexity, however, has been constrained by a lack of hypotheses to explain similarities and/or differences in signalling systems across taxa. To address this, we advocate incorporating a systems approach into studies of animal communication-an approach that includes comprehensive experimental designs and data collection in combination with the implementation of systems concepts and tools. A systems approach evaluates overall display architecture, including how components interact to alter function, and how function varies in different states of the system. We provide a brief overview of the current state of the field, including a focus on select studies that highlight the dynamic nature of animal signalling. We then introduce core concepts from systems biology (redundancy, degeneracy, pluripotentiality, and modularity) and discuss their relationships with system properties (e.g. robustness, flexibility, evolvability). We translate systems concepts into an animal communication framework and accentuate their utility through a case study. Finally, we demonstrate how consideration of the system-level organization of animal communication poses new practical research questions that will aid our understanding of how and why animal displays are so complex.

Content, cost, and context: A framework for understanding human signaling systems

“…In humans, yet again the situation can be more complex: for example, extravagant gift‐giving could be interpreted as an indicator of generosity (sender's character) or wealth (sender's capital). This potential multiplicity of meanings does not imply that the signal will not have a reliable probabilistic effect on receiver behavior; it simply implies that the effect will be different for different classes of receiver (e.g., males versus females, in‐group versus out‐group) …”

“…Behavioral ecologists have continued to develop and refine signaling theory since its introduction to anthropology in the late 1990s. While models of signaling theory in behavioral ecology initially focused on a single signal and pairwise interaction between sender and receiver, more recent work on animal communication has called attention to the complex reality of signaling systems, with the potential for multiple signal components and multiple interacting individuals . Here we review the foundations of signaling theory and synthesize these recent developments, discussing their relevance to human signaling systems.…”

Managing predators: The influence of kangaroo rat antipredator displays on sidewinder rattlesnake hunting behavior

“…Sand kicking is frequently inaccurate and misses the snake entirely, and kangaroo rats sometimes kick sand at objects that only vaguely resemble snakes (M. D. Whitford, G. A. Freymiller, R. W. Clark, personal observation); thus, sand kicking may provide imperfect information. As such, snakes may assess multiple, repeated signals prior to abandoning in order to ensure that the kangaroo rat has indeed detected the snake (Hebets et al, ) rather than abandon early and risk foregoing a potentially profitable encounter. Lastly, rattlesnakes are most vulnerable when elongated because they are not prepared to strike as they are when coiled (snakes strike by rapidly straightening the coils of their body); therefore, it is also possible that the rattlesnakes are choosing to remain in an ambush coil until they are certain the kangaroo rat has vacated the area and the snake can leave without being vulnerable to harassment.…”

“…Our ability to understand the function of specific predator‐deterrent signals is complicated by the fact that many prey species perform complex, multicomponent displays (Rowe, ). Individual elements within a display can encode information in numerous ways, including redundancy (same signal performed multiple times), degeneracy (multiple signals encoding identical information), or pluripotency (one signal encoding different information depending on context); signal elements can also interact to alter the intensity of the receiver's response or to provide emergent information (Hebets et al, ; Partan & Marler, ; Rowe & Guilford, ). Additionally, predators can respond to prey signaling in a variety of ways, including reduced overall probability of initiating an attack (Whitford, Freymiller, & Clark, ), targeting individuals of low physical quality (FitzGibbon & Fanshawe, ), or by abandoning pursuit and moving to a new hunting location (Barbour & Clark, ).…”

Frequency-channel dependent selectivity for temporal call characteristics in gray treefrogs, Hyla versicolor

“…Even the simplest animal signals vary in multiple dimensions (Hebets et al, 2016). For instance, all acoustic signals, even those characterized as relatively invariant 'pure' tones (e.g.…”