Nature visible only digitally

Abstract

Recent progress in imaging technology has enabled paleontologists to visualize all fossils inside solid rocks. Consequently, we can now imagine the natural worlds hidden not only inside our research materials but also within the opaque solids of everyday life. Here, we introduce the unique visual-spatial worlds that emerge from inside rocks and the creativity this discovery fosters.

Figure 1

Fossil excavation in the field (A) Somerset Island, Nunavut, Arctic Canada. Due to the absence of vegetation, strata over 1 billion years old are exposed during the summer. Microfossils of the earliest eukaryotes are hidden within these rocks. (B) Hokkaido Island, Japan. The photo depicts a pebble of a sedimentary rock cracked with a hammer. Numerous fossils of various marine organisms (white spots are shells) are visible on the surface. These are 85 million years old. In previous studies, fossils were extracted from hard rock using hammers and dental tools.

Figure 2

Inside rocks: Nature visible only digitally (A) The digitized rock obtained through grinding tomography and volume rendering. It contains internal information hidden within the opaque solid that cannot be perceived in the real world. (B–E) Numerous fossils visualized from the digitized rock. Each of them retains its internal structure. The rock sample, dated to 100 million years ago, was collected from Hokkaido Island. Volume rendering was performed using Amira 2022.1 (Thermo Fisher Scientific). The scale bar at the bottom right represents 10 mm for (A)–(D) and 1.5 mm for (E).

Figure 3

Comparison between X-ray computed tomography and grinding tomography (A) Synchrotron X-ray computed tomography. (B) Grinding tomography. The fossiliferous rock sample, which is 90 million years old, was collected from northern Hokkaido. The cross-sectional images used in (A) were obtained by X-ray phase-contrast tomography, with a pixel size of 48 μm/pixel at an energy of 113 keV, at BL20B2 of SPring-8, Japan. The images used in (B) were obtained through the same methods as in Figure 2. The scale bar at the bottom right represents 10 mm.