3.17 - Somatosensory Adaptations of Flying Mammals

Abstract

Cutaneous somatosensory specializations of the bat wing are considered in terms of their potential role in bat flight and aerial foraging. The bat wing is an elaborated hand with flexible digits between thin wing membranes. While bats can alter wing shape to improve their control of flight, the hand-wing has lost the ability for fine manipulation. Flight control may be enhanced by somatosensory feedback from orderly arrays of raised dome structures, each with a protruding hair, that are distributed across wing membrane surfaces. Domes and associated hairs contain concentrations of a common mammalian tactile receptor, the Merkel cell. Recordings from wing nerves suggest that these and other wing cutaneous receptors may be specialized for sensing surface airflow patterns that determine wing lift properties. The various types of wing tactile receptors may also improve prey capture, especially for insectivorous bats that must transfer captured insects from wing to mouth in mid-flight. The bat forearm and wing are well represented in somatosensory areas of the cortex. While most of the cortical body map reflects the standard mammalian pattern, the forearm representation shows an unusual reverse orientation. This variation in cortical representation pattern may relate to the forearm’s unique role in bat flight or foraging.