He examined fossils to arrive at this new classification of Protemnodon, a genus of extinct kangaroo that lived in Australia and New Guinea five million years ago and up to twelve thousand years before the present. For five years, Isaac Kerr, a young doctor in paleontology from Flinders University (Adelaide, Australia), photographed and 3D scanned more than 800 fossils scattered in the reserves of museums and universities in four countries. Identified one hundred and fifty years ago, the Protemnodon has benefited from renewed interest thanks to the discovery of new fossils between 2013 and 2019, including this almost complete specimen. Named Protemnodon viator, this species was much larger than the others. Weighing up to 170 kilograms, about twice as much as the largest living marsupial, the red kangaroo, it could jump quite quickly and efficiently using its limbs. Other Protemnodon species lived on four legs. More than an article, it is a sum of 261 pages that Isaac Kerr published on April 14 in Megataxa.