The Terrific Skink bite force suggests insularity as a likely driver to exceptional resource use

Area of Science:

• Zoology
• Biomechanics
• Evolutionary Biology

Background:

• Museum collections house rare specimens crucial for scientific study.
• Rediscovery of species like Phoboscincus bocourti offers insights into evolutionary pressures.
• Phoboscincus bocourti, a skink from New Caledonia, was recently rediscovered.

Purpose of the Study:

• To investigate the biomechanical properties of Phoboscincus bocourti's bite.
• To determine if the skink's bite force is sufficient to prey on hard-shelled land crabs.
• To compare Phoboscincus bocourti's bite force with that of 44 other skink species.

Main Methods:

• CT and MRI scans of the holotype specimen of Phoboscincus bocourti.
• Segmentation of jaw muscles and bones for biomechanical modeling.
• Bite force estimation and comparison with prey exoskeleton hardness and other skink species.

Main Results:

• Phoboscincus bocourti possesses a significantly higher bite force than required to crush the exoskeleton of its land crab prey.
• This high bite force is greater than that of 44 other skink species studied.
• The skink's bite force is sufficient to overcome the hardness of its prey's exoskeleton.

Conclusions:

• Predation on hard-shelled crabs is a likely selective pressure driving the evolution of Phoboscincus bocourti's powerful bite.
• High bite force is essential for survival in resource-scarce, extreme island environments.
• Phoboscincus bocourti is an apex predator and the only known skink to consume hard-shelled land crabs.