Journal article
Anatomy of the lamprey ear: morphological evidence for occurrence of horizontal semicircular ducts in the labyrinth of Petromyzon marinus
Journal of anatomy, Vol.224(4), pp.432-446
04/2014
DOI: 10.1111/joa.12159
PMCID: PMC4098677
PMID: 24438368
Abstract
In jawed (gnathostome) vertebrates, the inner ears have three semicircular canals arranged orthogonally in the three Cartesian planes: one horizontal (lateral) and two vertical canals. They function as detectors for angular acceleration in their respective planes. Living jawless craniates, cyclostomes (hagfish and lamprey) and their fossil records seemingly lack a lateral horizontal canal. The jawless vertebrate hagfish inner ear is described as a torus or doughnut, having one vertical canal, and the jawless vertebrate lamprey having two. These observations on the anatomy of the cyclostome (jawless vertebrate) inner ear have been unchallenged for over a century, and the question of how these jawless vertebrates perceive angular acceleration in the yaw (horizontal) planes has remained open. To provide an answer to this open question we reevaluated the anatomy of the inner ear in the lamprey, using stereoscopic dissection and scanning electron microscopy. The present study reveals a novel observation: the lamprey has two horizontal semicircular ducts in each labyrinth. Furthermore, the horizontal ducts in the lamprey, in contrast to those of jawed vertebrates, are located on the medial surface in the labyrinth rather than on the lateral surface. Our data on the lamprey horizontal duct suggest that the appearance of the horizontal canal characteristic of gnathostomes (lateral) and lampreys (medial) are mutually exclusive and indicate a parallel evolution of both systems, one in cyclostomes and one in gnathostome ancestors.
Details
- Title: Subtitle
- Anatomy of the lamprey ear: morphological evidence for occurrence of horizontal semicircular ducts in the labyrinth of Petromyzon marinus
- Creators
- Adel Maklad - University of Mississippi Medical CenterCaitlyn Reed - University of Mississippi Medical CenterNicolas S Johnson - Great Lakes Science CenterBernd Fritzsch - University of Iowa
- Resource Type
- Journal article
- Publication Details
- Journal of anatomy, Vol.224(4), pp.432-446
- DOI
- 10.1111/joa.12159
- PMID
- 24438368
- PMCID
- PMC4098677
- NLM abbreviation
- J Anat
- ISSN
- 0021-8782
- eISSN
- 1469-7580
- Number of pages
- 15
- Grant note
- National Institute of Health (R01; DC012060‐01)
- Language
- English
- Date published
- 04/2014
- Academic Unit
- Iowa Neuroscience Institute; Biology; Craniofacial Anomalies Research Center
- Record Identifier
- 9984070216802771
Metrics
36 Record Views