Ever wanted to see inside the body of a crocodile in the highest of resolutions? Now you can, thanks to Ohio University Professor of Anatomy and Paleontology Larry Witmer. To understand dinosaur anatomy, he's turned to birds and crocodilians, their closest living relatives.

The thing about fossils is that there's so much of the animal that gets lost to eternity. The carcass rots away, or gets eaten by scavengers, and all that remains are the bones. They're useful, to be sure, but they only provide a partial picture. "Skeletonization is an inherently destructive process that can change the skeleton in important ways," Witmer explains on his lab's facebook page. So he takes intact corpses of modern avian dinosaurs (birds) and crocodilians (alligators, crocodiles, and gharials), freezes them, trucks them to a nearby Ohio hospital, and takes high-resolution CT scans.

Above: Witmer inspects his reptilian acquisition.

This time, he got his hands on an 8.5 foot long Siamese crocodile, probably in its thirties, that died of natural causes at a reptile facility called Alligator Adventure in South Carolina. (Alligator Adventure, it should be stated, is not an AZA accredited zoo.)


The Siamese crocodile (Crocodylus siamensis) is a freshwater variety, native to Indonesia, Laos, Cambodia, Burma, Thailand, Vietnam, and parts of Malaysia. They're classified as critically endangered, and are already limited to just a few spots in their range.

The lab has released photos of the process, as well as the results of the scan, on their facebook page. Witmer thinks he might now have the most detailed images of a croc's innards ever taken: "8.5 feet of croc, scanned at slices only 300 microns (less than 0.012 inches) thick, yielding well over 8000 slices."

Witmer picks his cars based on their ability to haul his frozen cargo. "Let the record show that a Ford Edge can comfortably accommodate a family of five and an eight-and-a-half-foot croc...but not at the same time."

Witmer prepares the croc for scanning.

In order to get the massive reptile to fit inside the narrow scanning tube, they had to turn it into a croc-sicle torpedo. The team first thawed the croc, cinched its limbs with rope to lay snug against the torso, and then refroze it.

Below are some preliminary images generated from the CT scan. In the image of the skull it is easy to see why the Siamese crocodile is sometimes thought of as "horned."

[WitmerLab at Ohio University]