Ossicular density in golden moles (Chrysochloridae)

J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2006 Dec;192(12):1349-57. doi: 10.1007/s00359-006-0163-0. Epub 2006 Aug 31.

Abstract

The densities of middle ear ossicles of golden moles (family Chrysochloridae, order Afrosoricida) were measured using the buoyancy method. The internal structure of the malleus was examined by high-resolution computed tomography, and solid-state NMR was used to determine relative phosphorus content. The malleus density of the desert golden mole Eremitalpa granti (2.44 g/cm3) was found to be higher than that reported in the literature for any other terrestrial mammal, whereas the ossicles of other golden mole species are not unusually dense. The increased density in Eremitalpa mallei is apparently related both to a relative paucity of internal vascularization and to a high level of mineralization. This high density is expected to augment inertial bone conduction, used for the detection of seismic vibrations, while limiting the skull modifications needed to accommodate the disproportionately large malleus. The mallei of the two subspecies of E. granti, E. g. granti and E. g. namibensis, were found to differ considerably from one another in both size and shape.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Ear Ossicles / anatomy & histology*
  • Ear Ossicles / diagnostic imaging
  • Magnetic Resonance Imaging / methods
  • Malleus / anatomy & histology
  • Malleus / diagnostic imaging
  • Moles / anatomy & histology*
  • Tomography, X-Ray Computed / methods