Extended Data Fig. 5: Stratigraphy and palaeomagnetic results of the upper part of the Walanae Formation, including the Calio excavation site.

The stratigraphy is based on the Cabenge-Pampanua road section reported previously¹⁹. Celebochoerus icons indicate the fluvial deposits that contained vertebrate fossils as described in the prior study¹⁹ and the current paper. The panel to the right shows the paleomagnetic results of 14 samples. The approximate stratigraphic levels of palaeomagnetic samples taken at a distance from the recorded road section are based on extrapolation using the measured strike and dip of 258°/60° (see Extended Data Fig. 1). Sample Sp9 yielded intermediate results. Horizontal error bars indicate the 95% confidence limit of the mean directions (α95) (see Extended Data Table 2). The low sampling density does not allow for a correlation with the geomagnetic polarity time scale; however, the Reverse polarities near Ciangkange (Sp6 and Sp9 to Sp11) likely fall within the Matuyama Chron, because the top of the underlying marine Burecing Member (Sp14) contains nannofossils pertaining to nannoplankton zone CN12, which ranges in age from 3.75 to 1.95 Ma (ref. ¹⁹). R = Reverse polarity, N = Normal polarity, I = Intermediate polarity. F1 = Celebochoerus fossil maxilla excavated from the Calio site and dated using coupled Uranium-series and Electron Spin Resonance (US-ESR) to a minimum of 1.04 Ma.