Ear pinnae in a neotropical katydid (Orthoptera: Tettigoniidae) function as ultrasound guides for bat detection
Early predator detection is a key component of the predator-prey arms race and has driven the evolution of multiple animal hearing systems. Katydids (Insecta) have sophisticated ears, each consisting of paired tympana on each foreleg that receive sound both externally, through the air, and internall...
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| Format: | Article |
| Language: | English |
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eLife Sciences Publications Ltd
2022-09-01
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| Series: | eLife |
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| Online Access: | https://elifesciences.org/articles/77628 |
| _version_ | 1817986033722064896 |
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| author | Christian A Pulver Emine Celiker Charlie Woodrow Inga Geipel Carl D Soulsbury Darron A Cullen Stephen M Rogers Daniel Veitch Fernando Montealegre-Z |
| author_facet | Christian A Pulver Emine Celiker Charlie Woodrow Inga Geipel Carl D Soulsbury Darron A Cullen Stephen M Rogers Daniel Veitch Fernando Montealegre-Z |
| author_sort | Christian A Pulver |
| collection | DOAJ |
| description | Early predator detection is a key component of the predator-prey arms race and has driven the evolution of multiple animal hearing systems. Katydids (Insecta) have sophisticated ears, each consisting of paired tympana on each foreleg that receive sound both externally, through the air, and internally via a narrowing ear canal running through the leg from an acoustic spiracle on the thorax. These ears are pressure-time difference receivers capable of sensitive and accurate directional hearing across a wide frequency range. Many katydid species have cuticular pinnae which form cavities around the outer tympanal surfaces, but their function is unknown. We investigated pinnal function in the katydid Copiphora gorgonensis by combining experimental biophysics and numerical modelling using 3D ear geometries. We found that the pinnae in C. gorgonensis do not assist in directional hearing for conspecific call frequencies, but instead act as ultrasound detectors. Pinnae induced large sound pressure gains (20–30 dB) that enhanced sound detection at high ultrasonic frequencies (>60 kHz), matching the echolocation range of co-occurring insectivorous gleaning bats. These findings were supported by behavioural and neural audiograms and pinnal cavity resonances from live specimens, and comparisons with the pinnal mechanics of sympatric katydid species, which together suggest that katydid pinnae primarily evolved for the enhanced detection of predatory bats. |
| first_indexed | 2024-04-14T00:04:14Z |
| format | Article |
| id | doaj.art-cab11b5a976643afbb5c5c163dd23a75 |
| institution | Directory Open Access Journal |
| issn | 2050-084X |
| language | English |
| last_indexed | 2024-04-14T00:04:14Z |
| publishDate | 2022-09-01 |
| publisher | eLife Sciences Publications Ltd |
| record_format | Article |
| series | eLife |
| spelling | doaj.art-cab11b5a976643afbb5c5c163dd23a752022-12-22T02:23:35ZengeLife Sciences Publications LtdeLife2050-084X2022-09-011110.7554/eLife.77628Ear pinnae in a neotropical katydid (Orthoptera: Tettigoniidae) function as ultrasound guides for bat detectionChristian A Pulver0https://orcid.org/0000-0001-9197-9960Emine Celiker1https://orcid.org/0000-0003-4988-7901Charlie Woodrow2https://orcid.org/0000-0001-7342-0792Inga Geipel3Carl D Soulsbury4https://orcid.org/0000-0001-8808-5210Darron A Cullen5https://orcid.org/0000-0002-6287-5086Stephen M Rogers6Daniel Veitch7https://orcid.org/0000-0003-4404-8498Fernando Montealegre-Z8https://orcid.org/0000-0001-5186-2186University of Lincoln, School of Life & Environmental Sciences, Joseph Banks Laboratories, Green Lane, Lincoln, United KingdomUniversity of Lincoln, School of Life & Environmental Sciences, Joseph Banks Laboratories, Green Lane, Lincoln, United KingdomUniversity of Lincoln, School of Life & Environmental Sciences, Joseph Banks Laboratories, Green Lane, Lincoln, United KingdomSmithsonian Tropical Research Institute, Balboa, Panama; CoSys Lab, Faculty of Applied Engineering, University of Antwerp, Antwerp, Belgium; Flanders Make Strategic Research Centre, Lommel, BelgiumUniversity of Lincoln, School of Life & Environmental Sciences, Joseph Banks Laboratories, Green Lane, Lincoln, United KingdomUniversity of Lincoln, School of Life & Environmental Sciences, Joseph Banks Laboratories, Green Lane, Lincoln, United KingdomUniversity of Lincoln, School of Life & Environmental Sciences, Joseph Banks Laboratories, Green Lane, Lincoln, United KingdomUniversity of Lincoln, School of Life & Environmental Sciences, Joseph Banks Laboratories, Green Lane, Lincoln, United KingdomUniversity of Lincoln, School of Life & Environmental Sciences, Joseph Banks Laboratories, Green Lane, Lincoln, United KingdomEarly predator detection is a key component of the predator-prey arms race and has driven the evolution of multiple animal hearing systems. Katydids (Insecta) have sophisticated ears, each consisting of paired tympana on each foreleg that receive sound both externally, through the air, and internally via a narrowing ear canal running through the leg from an acoustic spiracle on the thorax. These ears are pressure-time difference receivers capable of sensitive and accurate directional hearing across a wide frequency range. Many katydid species have cuticular pinnae which form cavities around the outer tympanal surfaces, but their function is unknown. We investigated pinnal function in the katydid Copiphora gorgonensis by combining experimental biophysics and numerical modelling using 3D ear geometries. We found that the pinnae in C. gorgonensis do not assist in directional hearing for conspecific call frequencies, but instead act as ultrasound detectors. Pinnae induced large sound pressure gains (20–30 dB) that enhanced sound detection at high ultrasonic frequencies (>60 kHz), matching the echolocation range of co-occurring insectivorous gleaning bats. These findings were supported by behavioural and neural audiograms and pinnal cavity resonances from live specimens, and comparisons with the pinnal mechanics of sympatric katydid species, which together suggest that katydid pinnae primarily evolved for the enhanced detection of predatory bats.https://elifesciences.org/articles/77628bushcricketbioacousticsultrasound hearing3D printingbat predationfossil |
| spellingShingle | Christian A Pulver Emine Celiker Charlie Woodrow Inga Geipel Carl D Soulsbury Darron A Cullen Stephen M Rogers Daniel Veitch Fernando Montealegre-Z Ear pinnae in a neotropical katydid (Orthoptera: Tettigoniidae) function as ultrasound guides for bat detection eLife bushcricket bioacoustics ultrasound hearing 3D printing bat predation fossil |
| title | Ear pinnae in a neotropical katydid (Orthoptera: Tettigoniidae) function as ultrasound guides for bat detection |
| title_full | Ear pinnae in a neotropical katydid (Orthoptera: Tettigoniidae) function as ultrasound guides for bat detection |
| title_fullStr | Ear pinnae in a neotropical katydid (Orthoptera: Tettigoniidae) function as ultrasound guides for bat detection |
| title_full_unstemmed | Ear pinnae in a neotropical katydid (Orthoptera: Tettigoniidae) function as ultrasound guides for bat detection |
| title_short | Ear pinnae in a neotropical katydid (Orthoptera: Tettigoniidae) function as ultrasound guides for bat detection |
| title_sort | ear pinnae in a neotropical katydid orthoptera tettigoniidae function as ultrasound guides for bat detection |
| topic | bushcricket bioacoustics ultrasound hearing 3D printing bat predation fossil |
| url | https://elifesciences.org/articles/77628 |
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