Annette Stowasser

Annette Stowasser , PhD

Assistant Professor Educator

Assistant Professor Educator

Rieveschl Hall

851 JD

A&S Biological Sciences - 0006

Professional Summary

Visual systems, Image Formation, Physiology


Staatlich gepruefter Augenoptiker und Augenoptikermeister: Hoehere Fachschule fuer Augenoptik Koeln, Germany, 1993

B.S.: Xavier University Cincinnati, USA, 2007 (Biology)

PhD: University of Cincinnati Cincinnati, USA, 2013 (Biology)

Research and Practice Interests

The Optical System and Image Formation of the Larval principal eyes E1 and E2 of Thermonectus mamoratus (sunburst diving beetle).

Sunburst diving beetle larvae are aquatic and highly efficient visual predators with unusual eyes and hunting behavior, which suggests a novel visual mechanism. The larva has 12 eyes. However, most unusual are the forward pointing principal eyes E1 and E2. E1 and E2 are tube shaped camera like eyes with a static cornea lens, a crystalline cone between lens and retina, and an unusually layered retina. During hunting, the larvae scan their visual field while approaching pray, such as mosquito larvae, by dorsal-ventral body movements. Prey capture occurs once the prey is within a defined distance range, which suggests that the beetle larva can visually estimate distances well. This behavior suggests that a focused image is projected into planes that lay on or within the layered retina for all image distances. To understand the underlying visual mechanism, we need to know the optics of the eyes. Optical properties such as focal length and chromatic aberration of the optical system’s components need to be known. These optical properties determine the location of the image plane within the eye depending on the wavelength of the light and object distance. Here, the focal lengths and chromatic aberration of the principal eyes will be measured which will allow to calculate the image distance depending on the object distance for different wavelengths after taking the refractive indices of the crystalline cone and retina into account.

Research Support

Grant: #IOS-1856241 Investigators:Buschbeck, Elke; Stowasser, Annette 08-01-2019 -07-31-2023 National Science Foundation Coordinated eye growth in sophisticated arthropod visual systems Role:Collaborator $499,999.00 Awarded Level:Federal

Abbreviated Publications

Peer Reviewed Publications

Stecher, N., Stowasser, A., Stahl, A., Buschbeck, E.K. Embryonic development of the larval eyes of the sunburst diving beetle Thermonectus marmoratus (Insecta:Dytiscidae): a morphological study. Evolution and Development (in print).

Nagarah, J. M., Stowasser, A., Parker, R., Asari, H. and Wagenaar D. A. (2015). Optically transparent multi–suction electrode arrays. Front. Neurosci. 9, art. no. 384. 

Stowasser, A., Mohr, S., Buschbeck, E., & Vilinsky, I. (2015). Electrophysiology Meets Ecology: Investigating How Vision is Tuned to the Life Style of an Animal using Electroretinography. Journal of Undergraduate Neuroscience Education13(3), A234.

Stowasser, A., & Buschbeck, E. K. (2014). Multitasking in an eye: How the unusual organization of the principal larval eyes of Thermonectus marmoratus allows for far and near vision and might aid in depth perception. The Journal of Experimental Biology, jeb-098624.

Bland, K., Revetta, N. P., Stowasser, A., & Buschbeck, E. K. (2014). Unilateral range finding in diving beetle larvae. The Journal of experimental biology,217(3), 327-330.

Stowasser, A., & Buschbeck, E. K. (2012). Electrophysiological evidence for polarization sensitivity in the camera-type eyes of the aquatic predacious insect larva Thermonectus marmoratusThe Journal of experimental biology,215(20), 3577-3586.

Stowasser, A., Rapaport, A., Layne, J. E., Morgan, R. C., & Buschbeck, E. K. (2010). Biological bifocal lenses with image separation. Current Biology20(16), 1482-1486.

Brent, B., Stowasser, A. (2009) Impact of Lonicera maackii on Decomposition Rates of Native Leaf Litter in a Southwestern Ohio Woodland. The Ohio Journal of Science,109:43-47.


Stowasser, A., & Buschbeck, E. K. (2014). How aquatic water-beetle larvae with small chambered eyes overcome challenges of hunting under water.Journal of Comparative Physiology A200(11), 911-922.


Poster Presentations

Stowasser, A., Wagenaar, D. A. (2014. ) Simultaneous voltage-sensitive dye (VSD) imaging of both sides of leech ganglia .Neuroscience, Washington. . Level:International

Stowasser, A., Buschbeck, E. K. (2012. ) What do sunburst diving beetle larvae see? The role of polarization sensitivity .International Congress of Neuroethology, College Park, MD. . Level:International

Valinsky, I., Stowasser, A., Buschbeck, E. K. (2012. ) Electroretinograms of ‘Wild’ Arthropod Eyes .Neuroscience, New Orleans, TX. . Level:International

Stowasser, A., Rapaport, A., Layne, J. E. Buschbeck, E. K. (2010. ) Two eyes in one: The bizarre optics of the principal eye two of the sunburst diving beetle larva .International Congress of Neuroethology, Salamanca, Spain. . Level:International

Maksimovic, S., Stowasser, A., Cook, T., Buschbeck, E. K. (2009. ) Two eyes in one: The bizarre organization of the principal eyes of the Sunburst diving beetle larva .Neuroscience, Chicago, IL. . Level:International