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Abstract Scientific associations exist to serve their members and advance their science. They also provide a platform for scientists to communicate their science and engage with the public, such as hosting free resources on their web pages and organizing outreach activities with local communities. Historically, scientific associations were often internally focused. Despite the common stereotype of exclusive clubs of gentleman naturalists, there are numerous examples since the 17th century of scientific associations encouraging public engagement. This became increasingly common, and throughout the last several decades, scientific associations like the American Association for Anatomy (AAA) have been working to make changes in how science, scientists, and the public work together to produce the best scientific outcomes. This viewpoint defines different levels of relationships between the scientist and the public and how they affect outcomes related to the public's trust in science and scientists. It then provides a historical perspective on how associations have contributed to the communication of science. Lastly, it discusses the role of associations in science communication and public engagement and whether it is important for associations and why. It concludes with examples of the strategic programs of AAA that demonstrate how scientific associations can support public engagement, resulting in benefits to the public, scientists, and the anatomical sciences. 

The sphenoid bone articulates with multiple basicranial, facial, and calvarial bones, and in humans its synchondroses are known to contribute to elongation of the skull base and possibly to cranial base angulation. Its early development (embryological, early fetal) has frequently been studied in a comparative context. However, the perinatal events in morphogenesis of the sphenoid have been explored in very few primates. Using a cross-sectional age sample of non-human primates (n=39; 22 platyrrhines; 17 strepsirrhines), we used microcomputed tomographic (µCT) and histological methods to track age changes in the sphenoid bone. In the midline, the sphenoid expands its dimensions at three growth centers, including the sphenooccipital, intrasphenoidal (ISS) and presphenoseptal (PSept) synchondroses. Bilaterally, the alisphenoid is enlarged via appositional bone growth that radiates outward from cartilaginous parts of the alisphenoid during midfetal stages. The alisphenoid remains connected to the basitrabecular process of the basisphenoid via the alibasisphenoidal synchondrosis (ABS). Reactivity to proliferating cell-nuclear antigen is observed in all synchondroses, indicating active growth perinatally. Between mid-fetal and birth ages in Saguinus geoffroyi , all synchondroses decrease in the breadth of proliferating columns of chondrocytes. In most primates, the ABS is greatly diminished by birth, and is likely the earliest to fuse, although at least some cartilage may remain by at least one-month of age. Unlike humans, no non-human primate in our sample exhibits perinatal fusion of ISS. A dichotomy among primates is the orientation of the ABS, which is more rostrally directed in platyrrhines. Based on fetal Saguinus geoffroyi specimens, the ABS was initially oriented within a horizontal plane, and redirects inferiorly during late fetal and perinatal stages. These changes occur in tandem with forward orientation of the orbits in platyrrhines, combined with downward growth of the midface. Thus, we postulate that active growth centers direct the orientation of the midface and orbit before birth. 

Diffusible iodine-based contrast-enhanced computed tomography (diceCT) has emerged as a viable tool for discriminating soft tissues in serial CT slices, which can then be used for three-dimensional analysis. This technique has some potential to supplant histology as a tool for identification of body tissues. Here, we studied the head of an adult fruit bat ( Cynopterus sphinx ) and a late fetal vampire bat ( Desmodus rotundus ) using diceCT and µCT. Subsequently, we decalcified, serially sectioned and stained the same heads. The two CT volumes were rotated so that the sectional plane of the slice series closely matched that of histological sections, yielding the ideal opportunity to relate CT observations to corresponding histology. Olfactory epithelium is typically thicker, on average, than respiratory epithelium in both bats. Thus, one investigator (SK), blind to the histological sections, examined the diceCT slice series for both bats and annotated changes in thickness of epithelium on the first ethmoturbinal (ET I), the roof of the nasal fossa, and the nasal septum. A second trial was conducted with an added criterion: radioopacity of the lamina propria as an indicator of Bowman’s glands. Then, a second investigator (TS) annotated images of matching histological sections based on microscopic observation of epithelial type, and transferred these annotations to matching CT slices. Measurements of slices annotated according to changes in epithelial thickness alone closely track measurements of slices based on histologically-informed annotations; matching histological sections confirm blind annotations were effective based on epithelial thickness alone, except for a patch of unusually thick non-OE, mistaken for OE in one of the specimens. When characteristics of the lamina propria were added in the second trial, the blind annotations excluded the thick non-OE. Moreover, in the fetal bat the use of evidence for Bowman’s glands improved detection of olfactory mucosa, perhaps because the epithelium itself was thin enough at its margins to escape detection. We conclude that diceCT can by itself be highly effective in identifying distribution of OE, especially where observations are confirmed by histology from at least one specimen of the species. Our findings also establish that iodine staining, followed by stain removal, does not interfere with subsequent histological staining of the same specimen. 

Abstract ObjectivesThe aim of the present study is to broaden our knowledge of the ontogeny of cranial base cartilaginous joints in primates. Materials and MethodsA cross‐sectional age sample of 66 specimens from four platyrrhine and three strepsirrhine genera were studied using microcomputed tomography, histology, and immunohistochemistry. Specimens were segmented, reconstructed, and measured using Amira software. Ontogenetic scaling of palatal, presphenoid, and basisphenoid length relative to cranial length was examined using standardized major axis regression. After histological sectioning, selected specimens were examined using immunohistochemistry of antibodies to proliferating cell nuclear antigen. ResultsOur results support the hypothesis that the presphenoid in platyrrhines grows more rapidly compared with strepsirrhines, but this study establishes that most or all of this growth discrepancy occurs prenatally, and mostly at the presphenoseptal synchondrosis (PSept). All species have prolonged patency (here meaning absence of any bony bridging across the synchondrosis) of the intrasphenoidal and spheno‐occipital synchondroses (ISS). However, immunohistochemical results suggest growth is only rapid throughout infancy, and mitotic activity is slowing during juvenile ages. The same is indicated for the PSept. DiscussionThese results demonstrate that platyrrhines and strepsirrhines do not follow the pattern of early fusion of ISS seen in humans. In addition, these primates have a more prolonged patency and growth at PSept compared with humans. Finally, results reveal that in bushbabies and tamarins, as in humans, synchondroses remain cartilaginous for a prolonged period after chondrocyte proliferation has slowed or ceased. In light of these results, it is time to reassess related processes, such as differences in timing of brain expansion.