and dental development, it possesses no definitive hylobatid synapomorphies. The combined evidence suggests that nyanzapithecines were stem hominoids close to the origin of extant apes, and that hylobatid-like facial features evolved multiple times during catarrhine evolution.Hominoids underwent a major evolutionary radiation during the Miocene epoch, with over 40 widely recognized species in at least 30 genera 1 . Despite this multitude of taxa, only about one-third are known from any cranial remains, and no more than half a dozen preserve any significant portion beyond the face and palate 2 . Thus, much about hominoid cranial evolution remains poorly understood, especially with respect to the ancestral morphology that gave rise to the clade containing extant apes and humans. Importantly, the African fossil record lacks any reasonably complete hominoid crania between 17 and 7 million years (Myr) ago, and no cranial specimens are known at all from between 14 and 10 Myr (refs 3-6), greatly hampering the analysis of hominoid evolution. The KNM-NP 59050 cranium reported here was recovered from Napudet (South Turkana, Kenya) and dated to 13 Myr; it thus falls within this critical yet poorly represented period. The infant specimen is nearly complete, but is missing the deciduous dental crowns (Fig. 1a-d and Extended Data Fig. 1a-f). The unerupted adult dentition, brain endocast, and bony labyrinths were visualized using propagation phase-contrast X-ray synchrotron microtomography (PPC-SR-CT; Fig. 1e-h Locality and horizon. Napudet (2° 57′ N, 35° 52′ E), Turkana Basin, Kenya, Emunyan Beds, Brown Bedded Tuffs (Extended Data Fig. 2a).Geological age. 13 Myr. Diagnosis.A large species of Nyanzapithecus, with M 1 significantly larger than in N. pickfordi (P < 0.05), N. harrisoni (P < 0.01), and probably N. vancouveringorum ( Fig. 3a and Extended Data Table 1a; Cranial morphologyKNM-NP 59050 is a nearly complete but somewhat distorted cranium of an infant primate (Fig. 1). The cranium is slightly crushed bilaterally and the posterior portion of the basicranium is both broken and distorted. All the deciduous tooth crowns are broken off, but their roots are preserved. The permanent teeth are unerupted, with the right I 1 being visible in its crypt.The overall dimensions of KNM-NP 59050 are similar to those of Symphalangus crania of equivalent dental age, except for the maxillo-alveolar size, which is similar to Hoolock (Extended Data Table 1b). Relative to overall cranial size, the snout is small as in juvenile hylobatids, and smaller than in extant juvenile hominids . This difference between hylobatids and hominids persists into adulthood (Extended Data Fig. 4b, d), and assuming that N. alesi followed the same pattern, its snout would have been relatively small as an adult, unlike that of Afropithecus and Saadanius.The orbits appear large, but are well within the expected range for an extant juvenile hominoid of its size (Extended Data Fig. 4e). The orbits are slightly taller than wide, which may reflect the bilateral dist...
The ferrierite crystal structure has often been subject to discussion because of the possible lowering of symmetry from the space group Immm. It mainly occurs in nature with a fibrous crystal habit, and because of the existence of line/planar defects in the framework, texture and preferred orientation effects it has been difficult to obtain an exact crystallographic model based only on the results from powder diffraction data. Therefore, nano‐single‐crystal diffraction and tomography data have been combined in order to improve the refinement with a meaningful model. High‐quality single‐crystal data, providing reliable structural information, and tomography images have been used as input for a Rietveld refinement which took into account a phenomenological description of stacking disorder and the analytical description of the preferred orientation, by means of spherical harmonics for strong texture effects. This is one of the first examples of application of synchrotron nano‐diffraction for the structure solution of fibrous minerals of micrometre to nanometre size. The high quality of the crystals allowed collection of single‐crystal X‐ray diffraction data of up to 0.6 Å resolution, leading to an unambiguous solution and precise anisotropic refinement. Nano‐single‐crystal diffraction and phase contrast tomography data were collected at ID11 and the high‐resolution powder diffraction patterns at ID22 of the European Synchrotron Radiation Facility. This detailed crystallographic characterization provides a basis for understanding the potential of ferrierite for toxicity and carcinogenicity.
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