Sexually selected weapons can wear out, decreasing their effectiveness in combat

Area of Science:

• Evolutionary biology
• Animal behavior
• Morphological diversity

Background:

• Sexual selection leads to elaborate animal weapons.
• Morphological variation in these weapons is often attributed to genetics and environment.
• The impact of weapon wear on morphology and function is understudied.

Purpose of the Study:

• To investigate if sexually selected weapons wear out with use.
• To determine if weapon wear affects an individual's fighting ability.
• To explore weapon wear as a factor in morphological diversity and combat frequency.

Main Methods:

• Experimental manipulation of weapon usage in animals.
• Quantification of weapon shape changes after repeated use.
• Assessment of fighting ability in individuals with worn vs. unworn weapons.

Main Results:

• Sexually selected weapons showed significant wear from repeated use.
• Weapon wear led to changes in weapon shape.
• Individuals with worn weapons exhibited decreased fighting ability.

Conclusions:

• Weapon usage can contribute to morphological diversity within species.
• Weapon wear can influence contest outcomes by reducing fighting ability.
• Limited effective weapon use due to wear may influence combat frequency in animals.