_NEWS Ichthyology

Imaging, Reimagined
At the Academy of Natural Sciences of Drexel university, researchers are using X-ray technology to better analyze their fish collections - and better preserve valuable specimens, too.

_John Lundberg

Lundberg is an emeritus professor in the College of Arts and Sciences and emeritus curator of the Academy.

With the simple click of a mouse, a longer, richer, and increasingly valuable life is bestowed upon the deeply treasured dead things of the Academy of Natural Sciences of Drexel University. Using high-tech imaging equipment, scientists in the department of ichthyology are permanently digitizing nearly 3,000 type specimens, those prized “originals” that give tremendous value to any natural history collection.

This state-of-the-art imaging system now used by the Academy has changed the way scientists study fish, as well as how they protect and share biological collections. This digital system, acquired in 2008, replaced the outdated film and chemical setup and reduces a once tortuous process in the darkroom to a few seconds.

The Academy is one of only a few institutions using this digital X-ray system for imaging specimens.

“Digital images capture minute anatomical detail and increase the accuracy and precision of complex morphological description and understanding,” says department curator John Lundberg.

The department has already digitized roughly 1,500 type specimens (a “type” is the specimen on which species descriptions and scientific names are based). Academy staff members digitally photograph each specimen and then use the equipment to create a high-quality radiograph of the fish, which allows researchers to view the specimen from the inside out, or more like “the outside, through.”

Every living thing on Earth possesses features, or “characters,” used by scientists to distinguish one species from another. In fishes, many of these characters occur in the skeleton, such as the bones of the fins or backbone. In order to physically examine the bones, scientists must first rely on the appetite of meat-eating dermestid beetles to pick clean a specimen, leaving only the skeleton, a rather lengthy process that leaves the fleshy parts of the specimen forever destroyed.

There are many benefits of these radiographs. An online database of these images allows researchers to study the specimens from anywhere in the world—a true benefit for a scientist with a limited research budget. And, sending a digital file is preferred over the risks involved in loaning a specimen through the mail.

“Type specimens are so special—you don’t want to take a chance on losing them or damaging them,” Lundberg says.