Nuclear techniques confirm crocodile was dinosaur eater

Research on the fossils, which were discovered in 2010, has been carried out by scientists from the Australian Age of Dinosaurs Museum in association with the University of New England, and has been published in the journal Godwana Research.

Early neutron imaging of one of the rock fragments from the shattered boulder in which the fossils were found detected bones of the small chicken-sized juvenile dinosaur in the gut. ANSTO Senior Instrument Scientist Joseph Bevitt said the dinosaur bones were entirely embedded within the dense ironstone rock and were discovered serendipitously using the Dingo thermal neutron radiography/tomography/imaging station at the OPAL research reactor at Lucas Heights in New South Wales.

"In the initial scan in 2015, I spotted a buried bone in there that looked like a chicken bone with a hook on it and thought straight away that it was a dinosaur," Bevitt said. "Human eyes had never seen it previously, as it was, and still is, totally encased in rock.”

Further high-resolution scans using Dingo and the Imaging and Medical beamline at ANSTO's Australian Synchrotron, carried out over a number of years, confirmed the findings and built a detailed picture.

Bevitt and research team leader Matt White pictured with one of the samples on the with the sample on the Imaging and Medical beamline at the Australian Synchrotron (Image: ANSTO)

It is believed to be the first time a synchrotron beamline has been used in this way. The full intensity of the synchrotron X-ray beam was used to achieve the results on dense rock, and new software mechanisms were developed to process and merge different data sets from the fragmented crocodile, enabling it to be reconstructed as a digital, 3D "jigsaw puzzle". To confirm the dinosaur was actually in the gut of the crocodile, the team observed infilled worm tunnels, plant roots and geological features that extended between rock fragments, gathering further evidence from the chemistry of the rock.

"The results were outstanding in providing an entire picture of the crocodile and its last meal, a partially digested juvenile dinosaur," Bevitt said.

Investigators think it likely that the 2-2.5 metre long crocodile - now known as Confractosuchus sauroktonos, which translates as 'the broken crocodile dinosaur killer' - was caught up in a megaflood event, in which it was buried and died suddenly.

The fossils are now on display at the museum, which is in Queensland.