Image of the Week - 14 October 2003

Catfish Otoliths

Otoliths of ray-finned fish, like otoconia of tetrapods, are acellular composites of proteins and calcium carbonate that convey linear accelerations to sensory hair cells. They are essential components of the vestibular system; animals that lack otoliths or otoconia cannot keep their balance. Otoliths nucleate early during ear development and grow throughout life; their extravagant shapes differ substantially among otolithic organs and among species. This composite of images taken with the ITG's scanning electron microscope shows the three otoliths of the channel catfish, Ictalurus punctatus: from the top, the lapillus of the utricle, the sagitta of the sacculus, and the asteriscus of the lagena. Bar = 1 millimeter.

Image Courtesy: Amy Barbour and Richard Kollmar, Department of Molecular and Integrative Physiology

Contact: abarbour@uiuc.edu, rkollmar@uiuc.edu