Morphological Variation in the Dentition and Skull of the Australian Ghost Bat, Macroderma-Gigas (Microchiroptera, Megadermatidae)

Abstract

Morphological variation in the dentition and some cranial characters of the Australian ghost bat, Macroderma gigas, is reviewed by means of univariate and multivariate analyses. Specimens examined are drawn from existing populations across northern Australia; also included for parts of this study are mummified remains from southern central South Australia and late Pleistocene subfossil specimens from south-western Western Australia. No clear-cut geographic pattern in morphological variation in M. gigas is indicated by multivariate anlysis (i.e. principal components analysis), although there is some evidence for clinal variation from univariate analysis (i.e. Scheffe's multiple-comparions procedure). Northern Australian ghost bats (with the exception of north-eastern Australian indiv~duals) tend to be smaller than their southern counterparts. Sexual dimorphism appears to be low. Independent patterns of covariation among characters are extracted by principal components analysis: cheek tooth widths cluster separately from lengths; lengths and widths of the same teeth cluster separately from those of occluding teeth; and cranial measurements cluster separately from tooth measurements. Patterns in the data suggest that the number of characters needed to be examined in future morphometric studies of the vulnerable ghost bat can be significantly reduced.