Researchers found that scorpion stingers and pincers contain metals including zinc, manganese and iron, and said the pattern points to evolution rather than chance [1]. The study examined 18 scorpion taxa from a Smithsonian National Museum of Natural History collection and used high-resolution scanning electron microscopy and micro-X-ray fluorescence imaging to map the weapons [1].
Sam Campbell said the metal content was not a new discovery, but the team wanted to know why it was there. “That the metals are there has been known since the 1990s,” Campbell said. “What we didn’t know was whether scorpions evolved to be like that or if it was accidental and they were just picking the metals up from the environment.” [1]
In most of the specimens studied, zinc was highly concentrated at the extreme tip of the aculeus, while manganese often dominated the area just below the tip [1]. Campbell said zinc helps keep the stinger hard, saying, “Zinc has all to do with hardness and ensuring that we retain the strength of the tip of the stinger” [1].
Campbell and colleagues published the findings in the Journal of The Royal Society Interface [1].
