Formants provide honest acoustic cues to body size in American alligators

9Citations
Citations of this article
41Readers
Mendeley users who have this article in their library.

This artice is free to access.

Abstract

In many vertebrates, acoustic cues to body size are encoded in resonance frequencies of the vocal tract ("formants"), rather than in the rate of tissue vibration in the sound source ("pitch"). Anatomical constraints on the vocal tract's size render formants honest cues to size in many bird and mammal species, but it is not clear whether this correlation evolved convergently in these two clades, or whether it is widespread among amniotes (mammals, birds, and non-avian reptiles). We investigated the potential for honest acoustic cues in the bellows of adult American alligators and found that formant spacing provided highly reliable cues to body size, while presumed correlates of the source signal did not. These findings held true for both sexes and for all bellows whether produced in or out of water. Because birds and crocodilians are the last extant Archosaurians and share common ancestry with all extinct dinosaurs, our findings support the hypothesis that dinosaurs used formants as cues to body size. The description of formants as honest signals in a non-avian reptile combined with previous evidence from birds and mammals strongly suggests that the principle of honest signalling via vocal tract resonances may be a broadly shared trait among amniotes.

Cite

CITATION STYLE

APA

Reber, S. A., Janisch, J., Torregrosa, K., Darlington, J., Vliet, K. A., & Fitch, W. T. (2017). Formants provide honest acoustic cues to body size in American alligators. Scientific Reports, 7(1). https://doi.org/10.1038/s41598-017-01948-1

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free