Data from: Reversal to air-driven sound production revealed by a molecular phylogeny of tongueless frogs, family Pipidae

BACKGROUND: Evolutionary novelties often appear by conferring completely
new functions to pre- existing structures or by innovating the mechanism
through which a particular function is performed. Sound production plays a
central role in the behavior of frogs, which use their calls to delimit
territories and attract mates. Therefore, frogs have evolved complex vocal
structures capable of producing a wide variety of advertising sounds. It
is generally acknowledged that most frogs call by moving an air column
from the lungs through the glottis with the remarkable exception of the
family Pipidae, whose members share a highly specialized sound production
mechanism independent of air movement. RESULTS: Here, we performed
behavioral observations in the poorly known African pipid genus
Pseudhymenochirus and demonstrate that sound production in this aquatic
frog is air-driven. However, morphological comparisons revealed an
indisputable pipid nature of Pseudhymenochirus larynx. To place this
paradoxical pattern into an evolutionary framework, we reconstructed
robust molecular phylogenies of pipids based on complete mitochondrial
genomes and nine nuclear protein-coding genes that coincided in placing
Pseudhymenochirus nested among other pipids. CONCLUSIONS: We conclude that
although Pseudhymenochirus has evolved a reversal to the ancestral
non-pipid condition of air-driven sound production, the mechanism through
which it occurs is an evolutionary innovation based on the derived larynx
of pipids. This strengthens the idea that evolutionary solutions to
functional problems often emerge based on previous structures, and for
this reason, innovations largely depend on possibilities and constraints
predefined by the particular history of each lineage.