Subject: STATO-ACOUSTIC ORGAN and cochlea From: Kevin Austin <kevin.austin@xxxxxxxx> Date: Mon, 8 Oct 2007 10:18:27 -0400 List-Archive:<http://lists.mcgill.ca/scripts/wa.exe?LIST=AUDITORY>I am reading on: SENSORY ORGANS: STATO-ACOUSTIC ORGAN http://aquaticpath.umd.edu/fhm/ear.html Is the term "lateral organ' an oversimplification of a multi-dimensional process for the transduction of vibration / pressure waves / positional information? The article notes: Like semicircular canals, otolith chambers are lined with squamous epithelium and filled with endolymph. Maculae are flattened on the ventral surface of the chambers above which (and in contact with the sensory cell hairs) are suspended the otoliths. This sounds like a version of the cochlea, and I read that the cochlea and the canals share the same endolymph, all being part of the labyrinth. And for some evolutionary reason, the endolymph has potassium as the depolarizing agent of the hair cells, possibly because of the increased electrical gradient provided? http://en.wikipedia.org/wiki/Endolymph Could someone point me to an article that would answer my question; Is the cochlea the evolutionary end of the lateral organ? Thanks Kevin