Go big or go fish: morphological specializations in carnivorous bats

Area of Science:

• Evolutionary biology
• Comparative anatomy
• Mammalogy

Background:

• Specialized carnivory is rare in mammals, with bats exhibiting multiple independent evolutionary origins.
• Phenotypic traits linked to the recent evolution of carnivory in bats remain poorly understood.

Purpose of the Study:

• To identify phenotypic traits associated with ecological divergence in carnivorous bats.
• To investigate morphological convergence among bats with independent carnivory origins and other carnivorous mammals.

Main Methods:

• Geometric morphometrics applied to skull shape analysis.
• Phylogenetic comparative analyses to link morphology with diet and evolutionary history.

Main Results:

• Carnivorous bats are larger and possess skull shapes enhancing bite force at wide gapes, occupying a subset of insectivorous bat morphospace.
• Piscivorous bats show distinct cranial adaptations for high bite force at narrow gapes.
• Positive allometry in rostrum elongation observed in all animal-eating bats, potentially aiding in capturing larger prey.

Conclusions:

• Skull morphology in carnivorous bats shows convergence, particularly for increased bite force.
• Bat carnivory evolution involves distinct adaptations, with piscivores being morphologically unique.
• Bat cranial shapes for carnivory share similarities with generalized carnivorans but are optimized for bite force over gape.