A joint team of paleontologists has now for the first time analyzed bone structures in 400 million-year-old fossils of marine life at unprecedentedly high resolution and in 3D. To be able to view these structures, tomography experts at the Helmholtz-Zentrum Berlin (HZB) examined the samples under the focused ion beam of a scanning electron microscope to calculate 3D images from the data, achieving resolutions in the nanometre range using technology that was initially developed to study battery corrosion.