RangeVision Spectrum helps scientists 3D scan skulls of proto-mammals

Last year Saint Petersburg State University celebrated the 160th anniversary of its graduate Vladimir P. Amalitsky, a Russian paleontologist. He was first to compare his own findings to various fossils from Africa and India and hypothesize that all continents on Earth used to be a single supercontinent . Now we call this supercontinent Pangaea.

The anniversary was celebrated with an exhibition. It included plaster casts of skulls that had belonged to three proto-mammals named Scutosaurus, Inostrancevia, and Dvinosaurus. The original skulls were found by Amalitsky during excavations on the banks of the Northern Dvina River in North European Russia.

The plaster casts were also made by the paleontologist in the early 20th century. So now, more than a hundred years later, these copies are valuable as a memory of the scientist, too. But SPbU staff needed to restore the plaster casts before putting them on display. The problem was to reconstruct the original form of the skulls.

There was another problem as well. Massive plaster casts may be impressive to look at, but they are too cumbersome to work with. There had to be some way to digitize the artifacts without losing the tiniest details of their form and texture. RangeVision Spectrum, a professional 3D scanner, was chosen for this difficult job.

Restoration

Ekaterina Ageeva, a graduate of the SPbU restoration faculty, became the author of the project. Actually, it was her graduation work. All three proto-mammals in question lived during the Permian Period, more than 250 million years ago.

Scutosaurus was a massive herbivore about three meters long. Its skin was covered in bony deposits forming scales, hence the name (Scutosaurus means ‘shield lizard’ in Latin). According to one version, Scutosaurus spent half its life in water — just like a hippo. This reptile was the first to be found and exhibited in Russia as a skeleton.

Plaster cast of the Scutosaurus skull after restoration. One of the zygomatic bones was reconstructed.

Inostrancevia was a large carnivore measuring more than three meters in length. Its enormous fangs could grow to be 30 cm long, changing over time. Amalitsky named the reptile Inostrancevia alexandri after geologist Alexandr Inostrancev, his scientific mentor. The copy of the Inostrancevia skull required its nasal bones to be restored.

Plaster cast of the Inostrancevia skull with restored nasal bones.

Dvinosaurus was another carnivore, but much smaller. These amphibians, about one meter long, spent their entire lives in water. They breathed through external gills that were sticking out to the sides of their heads. This copy of the Dvinosaurus skull was covered in chips and scratches that had to be painted over.

Plaster cast of the Dvinosaurus skull. Chips and scratches were carefully painted over.

3D Scanning

After the restoring process was finished, associate professor of the SPbU vertebrate zoology faculty Dmitry Grigoryev began to solve the scanning problem. He employed a 3D scanner RangeVision Spectrum to make exact 3D copies of the artifacts. As he put it, “virtual fossils allow us to avoid using real museum artifacts for education”.