Morphological determinants of carrier frequency signal in katydids (Orthoptera): a comparative analysis using biophysical evidence

Publication Type:Journal Article
Year of Publication:2017
Authors:Montealegre-Zapata, F, Ogden, J, Jonsson, T, Soulsbury, CD
Journal:Journal of Evolutionary Biology
Date Published:Apr-09-2018

Male katydids produce mating calls by stridulation using specialized structures on the forewings. The right wing (RW) bears a scraper connected to a drum-like cell known as the mirror and a left wing (LW) that overlaps the RW and bears a serrated vein on the ventral side, the stridulatory file. Sound is generated with the scraper sweeping across the file, producing vibrations that are amplified by the mirror. Using this sound generator, katydids exploit a range of song carrier frequencies (CF) unsurpassed by any other insect group, with species singing as low as 600 Hz and others as high as 150 kHz. Sound generator size has been shown to scale negatively with CF, but such observations derive from studies based on few species, without phylogenetic control, and/or using only the RW mirror length. We carried out a phylogenetic comparative analysis involving 94 species of katydids to study the relationship between LW and RW components of the sound generator and the CF of the male's mating call, while taking into account body size and phylogenetic relationships. The results showed that CF negatively scaled with all morphological measures, but was most strongly related to components of the sound generation system (file, LW and RW mirrors). Interestingly, the LW mirror (reduced and non-functional) predicted CF more accurately than the RW mirror, and body size is not a reliable CF predictor. Mathematical models were verified on known species for predicting CF in species for which sound is unknown (e.g. fossils or museum specimens).

Short Title:J. Evol. Biol.
BioAcoustica ID: 
Taxonomic name: 
Acanthacara acuta (Classification), Ancistrocercus Ancistrocercus circumdatus (Classification), Ancistrocercus Ancistrocercus excelsior (Classification), Arachnoscelis arachnoides (Classification), Artiotonus artius (Classification), Artiotonus captivus (Classification), Artiotonus tinae (Classification), Balboana tibialis (Classification), Championica Auchenacophora walkeri (Classification), Chibchella nigrospecula (Classification), Chondroderella borneensis (Classification), Conocephalus Anisoptera saltator (Classification), Copiphora brevirostris (Classification), Copiphora gorgonensis (Classification), Copiphora gracilis (Classification), Copiphora rhinoceros (Classification), Daedalellus waehnerorum (Classification), Diacanthodis granosa (Classification), Docidocercus chlorops (Classification), Docidocercus gausodontus (Classification), Docidocercus gigliotosi (Classification), Drepanoxiphus angustelaminatus (Classification), Neoconocephalus affinis (Classification), Panacanthus cuspidatus (Classification), Panacanthus gibbosus (Classification), Panacanthus intensus (Classification), Panacanthus lacrimans (Classification), Panacanthus pallicornis (Classification), Panacanthus varius (Classification), Panoploscelis specularis (Classification), Parascopioricus cordillericus (Classification), Pemba cochleata (Classification), Phlugis poecila (Classification), Phymonotus jacintotopos (Classification), Pristonotus tuberosus (Classification), Promeca perakana (Classification), Promeca sumatrana (Classification), Ragoniella pulchella (Classification), Scopiorinus carinulatus (Classification), Scopiorinus impressopunctatus (Classification), Scopiorinus mucronatus (Classification), Stetharasa exarmata (Classification), Supersonus aequoreus (Classification), Supersonus piercei (Classification), Supersonus undulus (Classification), Teleutias akratonos (Classification), Teleutias castaneus (Classification), Teleutias fasciatus (Classification), Tettigonia viridissima (Classification), Trichotettix pilosula (Classification), Triencentrus atrosignatus (Classification), Tympanophyllum Tympanophyllum arcufolium (Classification), Typophyllum bolivari (Classification), Typophyllum egregium (Classification), Typophyllum erosifolium (Classification), Typophyllum morrisi (Classification), Typophyllum mortuifolium (Classification), Typophyllum onkiosternum (Classification), Typophyllum trapeziforme (Classification), Typophyllum zingara (Classification), Uchuca amacayaca (Classification), Uchuca halticos (Classification)
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith