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Hidden social complexity behind vocal and acoustic communication in non-avian reptiles

The Royal Society
Philosophical Transactions B
Authors:
Feng-Chun Lin
Feng-Chun Lin
Feng-Chun Lin
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Si-Min Lin at National Taiwan Normal University
Si-Min Lin
Stephanie S. Godfrey
Stephanie S. Godfrey
Stephanie S. Godfrey
  • This person is not on ResearchGate, or hasn't claimed this research yet.
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Abstract

Social interactions are inevitable in the lives of most animals, since most essential behaviours require interaction with conspecifics, such as mating and competing for resources. Non-avian reptiles are typically viewed as solitary animals that predominantly use their vision and olfaction to communicate with conspecifics. Nevertheless, in recent years, evidence is mounting that some reptiles can produce sounds and have the potential for acoustic communication. Reptiles that can produce sound have an additional communicative channel (in addition to visual/olfactory channels), which could suggest they have a higher communicative complexity, the evolution of which is assumed to be driven by the need of social interactions. Thus, acoustic reptiles may provide an opportunity to unveil the true social complexity of reptiles that are usually thought of as solitary. This review aims to reveal the hidden social interactions behind the use of sounds in non-avian reptiles. Our review suggests that the potential of vocal and acoustic communication and the complexity of social interactions may be underestimated in non-avian reptiles, and that acoustic reptiles may provide a great opportunity to uncover the coevolution between sociality and communication in non-avian reptiles. This article is part of the theme issue ‘The power of sound: unravelling how acoustic communication shapes group dynamics’.
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Hidden social complexity behind vocal
and acoustic communication in non-
avian reptiles
Feng-Chun Lin1, Si-Min Lin2 and Stephanie S. Godfrey1
1Department of Zoology, University of Otago, Dunedin, New Zealand
2School of Life Science, National Taiwan Normal University, Taipei, Taiwan
F-CL,0000-0003-3762-3335; S-ML,0000-0001-7080-706X; SSG,0000-0003-1014-4684
Social interactions are inevitable in the lives of most animals, since
most essential behaviours require interaction with conspecifics, such as
mating and competing for resources. Non-avian reptiles are typically
viewed as solitary animals that predominantly use their vision and
olfaction to communicate with conspecifics. Nevertheless, in recent years,
evidence is mounting that some reptiles can produce sounds and have
the potential for acoustic communication. Reptiles that can produce
sound have an additional communicative channel (in addition to visual/
olfactory channels), which could suggest they have a higher communicative
complexity, the evolution of which is assumed to be driven by the need
of social interactions. Thus, acoustic reptiles may provide an opportunity
to unveil the true social complexity of reptiles that are usually thought
of as solitary. This review aims to reveal the hidden social interactions
behind the use of sounds in non-avian reptiles. Our review suggests that
the potential of vocal and acoustic communication and the complexity
of social interactions may be underestimated in non-avian reptiles, and
that acoustic reptiles may provide a great opportunity to uncover the
coevolution between sociality and communication in non-avian reptiles.
This article is part of the theme issue ‘The power of sound: unravelling
how acoustic communication shapes group dynamics’.
1. Introduction
Non-avian reptiles have traditionally been viewed as solitary or non-social
animals [1], and thus have simple communicative needs. However, sociality
need not be seen as dichotomy (i.e. classifying animals as either social or
non-social [1]), since interactions with conspecifics are inevitable in the lives
of most animals. For example, attracting individuals of the opposite sex for
reproductive opportunities or competing for resources or territories with
conspecifics forms the foundation of a social interaction. Communication in
some form must accompany these interactions.
Sound is not normally associated with communication in non-avian
reptiles; indeed visual (e.g. body colours, body movements [2]), and olfac-
tory signals (e.g. chemicals or pheromones [3,4]) are considered to be more
common methods of communication in this group. However, recent evidence
is mounting that non-avian reptiles are not as silent as we assume [5,6].
Non-avian reptiles are capable of producing sounds, both via vocal appara-
tus (vocalization) and mechanically via the movement of their body (e.g.
producing sounds, such as hissing or snapping, or tail rattling in snakes
[7]). However, the extent to which sound communication is used in social
contexts in non-avian reptiles is poorly understood, and largely limited to a
few, well-studied taxa.
© 2024 The Author(s). Published by the Royal Society. All rights reserved.
Review
Cite this article: Lin F-C, Lin S-M, Godfrey SS.
2024 Hidden social complexity behind vocal and
acoustic communication in non-avian reptiles.
Phil. Trans. R. Soc. B 379: 20230200.
https://doi.org/10.1098/rstb.2023.0200
Received: 19 October 2023
Accepted: 8 January 2024
One contribution of 16 to a theme issue 'The
power of sound: unravelling how acoustic
communication shapes group dynamics’.
Subject Areas:
behaviour, evolution, ecology
Keywords:
signalling, social interactions, turtles, crocodiles,
lizards, the social complexity hypothesis for
communicative complexity
Author for correspondence:
Feng-Chun Lin
e-mail: kame224339@gmail.com,
olivia.lin@postgrad.otago.ac.nz
... Thus far, we have established that reptiles can produce and use a range of vocal and non-vocal acoustic signals. Following Lin et al. [110], we suggest that these signals may be used as mediators of complex social behaviours. Exploring how these signals may vary across populations could inform us about cultural behaviours in this group. ...
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... Lin et al. [48] emphasize the underestimated potential for vocal and acoustic communication in non-avian reptiles, traditionally considered solitary with reliance on vision and olfaction for interactions. Recent findings suggest that acoustic communication in these reptiles may be more common than previously thought, indicating a higher communicative complexity and more social interactions than assumed. ...
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