The structure of the túngara frog’s ears
Poster Number
32
Format
Poster Presentation
Faculty Mentor Name
Marcos Gridi-Papp
Faculty Mentor Department
Biological Sciences
Abstract/Artist Statement
Male túngara frogs call to attract females. While the male calls floating on the surface of the water, the female approaches him first on land and later in water, with her ears submerged just below the surface. Sound must travel and be detected in two mediums – air and water – before the female reaches the male. This is uncommon because most other frogs call from land and females can use airborne sound only to find the male. The ear morphology of the túngara frog might, therefore, have adaptations for the change in mediums experienced by the female during her approach of the male. To examine the morphology of the ear, we preserved the tissue of a frog’s head in paraformaldehyde and embedded it in glycol methacrylate resin. After the resin hardened into a block, we sliced it into 4 μm cuts, and mounted the cuts onto glass slides. Next, we stained the tissues with a solution of toluidine blue to facilitate visualization of the auditory morphology. We photographed the stained cuts and aligned the images to create a three-dimensional image and make quantitative comparisons between ears cut at slightly different orientations. Our preliminary data indicate that túngara frogs have relatively thick eardrums and an expanded extrastapes, which are features also found in animals like the African clawed frog, in which adults communicate underwater all the time. These features could potentially have a role in facilitating underwater hearing. We are currently preparing to test this hypothesis through experiments and comparison with close relatives of the túngara frog that call from land.
Location
DeRosa University Center, Ballroom
Start Date
25-4-2015 10:00 AM
End Date
25-4-2015 12:00 PM
The structure of the túngara frog’s ears
DeRosa University Center, Ballroom
Male túngara frogs call to attract females. While the male calls floating on the surface of the water, the female approaches him first on land and later in water, with her ears submerged just below the surface. Sound must travel and be detected in two mediums – air and water – before the female reaches the male. This is uncommon because most other frogs call from land and females can use airborne sound only to find the male. The ear morphology of the túngara frog might, therefore, have adaptations for the change in mediums experienced by the female during her approach of the male. To examine the morphology of the ear, we preserved the tissue of a frog’s head in paraformaldehyde and embedded it in glycol methacrylate resin. After the resin hardened into a block, we sliced it into 4 μm cuts, and mounted the cuts onto glass slides. Next, we stained the tissues with a solution of toluidine blue to facilitate visualization of the auditory morphology. We photographed the stained cuts and aligned the images to create a three-dimensional image and make quantitative comparisons between ears cut at slightly different orientations. Our preliminary data indicate that túngara frogs have relatively thick eardrums and an expanded extrastapes, which are features also found in animals like the African clawed frog, in which adults communicate underwater all the time. These features could potentially have a role in facilitating underwater hearing. We are currently preparing to test this hypothesis through experiments and comparison with close relatives of the túngara frog that call from land.