A biomechanical view on stinger diversity in scorpions

Area of Science:

• Zoology
• Biomechanics
• Evolutionary Morphology

Background:

• Scorpions utilize their telson (stinger) for defense, prey capture, and mating, exhibiting diverse stinging behaviors.
• The functional demands of varied stinging behaviors may influence the evolution of telson (stinger) shape.

Purpose of the Study:

• To investigate the diversity of scorpion telson shapes.
• To analyze the biomechanical properties of scorpion stingers using finite element analysis (FEA).

Main Methods:

• Morphological measurements of telson shape (curvature, tip angle) were taken.
• Finite element analysis (FEA) was used to simulate stingers under load, assessing strain energy and stress concentrations.
• Load force angle was optimized to determine the lowest strain energy for different telson shapes.

Main Results:

• Aculeus (stinger barb) length and height correlated with minimal strain energy.
• Optimal stinging angle differed from the tip angle by approximately 28.4°.
• More venomous species possess longer aculei with larger curvature, showing basal stress concentrations.
• Less venomous species or those with shorter, thicker aculei exhibited stress concentrations primarily at the tip.
• No significant difference in scaled strain energy was found between more and less venomous species groups.

Conclusions:

• Scorpion stingers appear to be biomechanically optimized, with shape variations potentially reflecting different stinging behaviors.
• Telson morphology may be influenced by venom potency and the specific functions of the stinger in different scorpion species.