Morphology and flight manoeuvrability in New World leaf-nosed bats (Chiroptera : Phyllostomidae)

The relationship between wing morphology and ability to manoeuvre through a n obstacle course was examined in five species of bats in the Neotropical f amily Phyllostomidae. These species represent a range of morphologies and f eeding adaptations: Tonatia silvicola, a surface-gleaning insectivore; Arti beus jamaicensis and A. literatus, canopy frugivores; and Carollia perspici llata and C castanea, understory frugivores. Bats of known morphology were presented with three different obstacle arrangements chosen in random order . In order to control for wing span, spacing between obstacles was scaled t o the wing span of the individual (1 x, 0.75 x, 0.5 x the wing span of the bat). Performance was measured as the number of times a bat hit an obstacle hard enough to deflect it. Morphological variables were analysed using pri ncipal components analysis and were summarized by the first two principal c omponents (PC): PC 1, 'size', with which size-related variables were strong ly, positively correlated; PC 2, 'camber', on which variables associated wi th maximum depth of wing camber weighted most heavily. Obstacle course perf ormance was significantly correlated with both size and camber at all obsta cle spacings: larger bats hit more obstacles, even though obstacle spacing was scaled to wing span, and bats with better ability to camber wings hit f ewer obstacles. These results show that bat species that forage in more clu ttered habitats are more likely to be small in size and/or have wings able to produce the high camber necessary to maintain lift at low flight speeds.