How to x-ray a fish
Pristis pectinata (Smalltooth sawfish). Credit: Sandra J. Raredon. © Source: Smithsonian Institution.
Lynne R. Parenti, How do you x-ray a fish? Inside the Smithsonian’s National Collection of Fishes, Australian National Maritime Museum, 26 October 2015
Have you explored the striking images on display in X-Ray Vision: Fish Inside Out? The Smithsonian Institution’s Traveling Exhibition Service (SITES) produced the exhibit on at the Australian National Maritime Museum until 28 February 2016; it features 40 black-and-white digital prints of x-rays or radiographs arranged in evolutionary sequence, taking visitors on a tour through the long stream of fish evolution.
Curators of the exhibition, Lynne Parenti and Sandra Raredon, work at the National Collection of Fishes at the National Museum of Natural History. Sandra prepares thousands of x-rays to help ichthyologists understand and document the diversity of fishes. Here, Lynne, a research curator, describes what’s involved in capturing these mesmerising x-ray images.
Radiographs or x-rays allow the study of the skeleton of a fish without dissecting or in any other way altering the specimen. Radiographs may be prepared of any specimen, often unique or rare specimens, or, alternatively, large samples in which a researcher wishes to compare features among a group of individuals.
The radiographic images in this exhibit largely follow scientific, not artistic, conventions: there is one specimen per frame, and that individual fish is facing left. When grouped together, they are done so to save time of radiograph preparation or to facilitate comparison.