The study, published in the journal Nature Communications, focused on the oriental rhinoceros beetle (Oryctes rhinoceros), a species found in tropical and subtropical regions of Asia. During mating, male beetles engage in fierce battles, using their horns to fight off rivals and gain access to females. To withstand the rigors of these battles and protect their soft internal organs, the beetles' exoskeletons must be extremely tough.
The researchers found that the hardening process is triggered by a hormone called ecdysone, which is released by the male beetles during mating. Ecdysone activates a cascade of biochemical reactions that lead to the formation of new bonds between the proteins in the beetle's exoskeleton, resulting in a dramatic increase in hardness.
The researchers also found that the hardening process is reversible. Once mating is complete and ecdysone levels drop, the beetle's shell gradually softens, allowing the beetle to move freely again.
This discovery provides important insights into the mechanisms by which beetles and other insects can control the properties of their exoskeletons. It could also lead to the development of new materials with similar properties, which would be useful in a variety of applications, such as body armor, sports equipment, and construction materials.
