Volume 37 #1

Contents

1. Relationship of the magnetic compass and vision in birds: in search of a receptor cell
2. What did adaptive optics give us for understanding the mechanisms of human color vision
3. Magnetic Navigation of Animals, Contrast Sensitivity of Vision, and the Weber-Fechner Law
4. Рeculiarities of control commands generation for oculographic interfaces under the conditions of vestibular impacts
5. "Acoustic window” in the mandibular of dolphins: evaluation of the bone thickness"
6. Changes in the spectral characteristics and the coherence of the rat olfactory bulb local field potentials under xylazine-tiletamine-zolazepam anesthesia
7. Automatic evaluation of the internal parameters of the onboard camera of a spacecraft from video data of dockings with the iss

The mandibular sound conduction hypothesis suggests that dolphins have functionally replaced the external pinna with an “acoustic window” in the low jaw. Using industrial tomography, the lower jaws 3D models of the odontocetes six species were built. In the obtained models, the analysis of the bone thickness in the area of the supposed “acoustic window” showed a dependence of the bone wall thickness on the size of the animal. The area of the greatest thinning of the lateral wall of the lower jaw in the studied samples was determined mainly in the upper angle of the proximal part of the lower jaw or near the lower angle of the lower jaw, and not in the center, as previously assumed.

Key words: hearing, toothed whales, acoustic window, lower jaw

DOI: 10.31857/S0235009223010079  EDN: AUDIQM

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