, March 5 -- Scientists have found a way to examine Charles Darwin's original specimens from his HMS Beagle voyage (1831-1836) without opening the nearly 200-year-old jars that preserve them.

The study focused on 46 historic specimens at London's Natural History Museum, including mammals, reptiles, fish, jellyfish, and shrimp collected by Darwin and other early naturalists. Researchers found that preservation methods varied by organism and time period. While mammals and reptiles were often treated with formalin before storage in ethanol, invertebrates were kept in a mix of fluids, including formalin, buffered solutions, or glycerol-based liquids.

Using a portable laser spectroscopy technique called Spatially Offset Raman Spectroscopy (S...