Vertebrate bodies illuminated by new imaging technique

Don't let these pictures keep you up at night. The creatures in them, such as this Macklot's python, are just specimens kept for scientific research. These images were created using new techniques developed by W. Leo Smith, an associate professor of ecology and evolutionary biology, along with graduate student Matt Girard and intern Chesney Buck.

Researchers using traditional ways of photographing stained animal bones and cartilage can often encounter difficulty when trying to keep a specimen, with all of its bones, cartilage and skin, together. It can be especially tricky when dealing with all the tiny bones of a creature like this plains spadefoot toad.

In both old and new photographing techniques, stomach enzymes from a cow are used to remove the muscle tissue from specimens like this royal threadfin, leaving just skin, bone, connective tissue and nerves. Without that muscle tissue, the remaining specimen can be quite limp.

The new technique developed by researchers embeds the de-fleshed bones in a gelatin and glycerine mix, which then thickens around the skeleton. This enables the scientists to pose the specimens, such as this plainfish midshipman — placing the bones carefully in the positions they want.

Animals can be configured in novel shapes and configurations not previously possible. Seeing where bones connect and where there are gaps can help scientists understand not only how animals move, but can also help to shed light on evolutionary relationships between species.

Posing the specimens is just one step of the process, though. In both traditional methods and this new method, the creatures' bones are stained with a red dye to help make them more visible for the camera.

Through sheer luck, the team also found that the traditional red dye used to stain animal bones glows fluorescent red under high-energy blue light. This technique enabled them to take much clearer pictures of the bones, as everything else in the image falls away to darkness.

The gelatin mixture is also translucent, so the stained bones are still visible for the camera, as you can see in this blue-lipped tree lizard. After the photo shoot, the gelatin can be washed off without damaging the animal bones.

Other researchers are now using these methods to take photos of their own work. Scientists are hopeful that the ability to more easily position specimens and photograph them with greater precision will help them to better understand evolution, and how species like this big brown bat fly (or walk or crawl or slither) through the world.