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Fossils from the Fayum Depression, Egypt, are crucial for understanding anthropoid evolution due to the abundance of taxa and the time interval they represent (late Eocene to early Oligocene). Dietary and foraging behavioral interpretations suggest fruits were their dominant food source, although hard foods (e.g., seeds and nuts) and leaves could have been important dietary components for particular groups. In this study, we compare dental chipping patterns in five Fayum primate genera with chipping data for extant primates, to assess potential hard object feeding in early anthropoids. Materials and MethodsOriginal specimens were studied (Aegyptopithecus:n = 100 teeth;Parapithecus:n = 72,Propliopithecus:n = 99,Apidium:n = 82;Catopithecus:n = 68); with the number, severity, and position of chips recorded. Dental caries was also recorded, due to its association with soft fruit consumption in extant primates. ResultsTooth chipping was low across all five genera studied, with a pooled chipping prevalence of 5% (21/421). When split into the three anthropoid families represented, chipping prevalence ranged from 2.6% (4/154) in Parapithecidae, 6% (12/199) in Propliopithecidae, and 7.4% (5/68) in Oligopithecidae. Three carious lesions were identified in Propliopithecidae. DiscussionThe chipping prevalence is low when compared to extant anthropoids (range from 4% to 40%) and is consistent with a predominantly soft fruit diet, but not with habitual hard food mastication. The presence of caries supports consumption of soft, sugary fruits, at least in Propliopithecidae. Our results add support for low dietary diversity in early anthropoids, with soft fruits as likely dominant food sources. 

The living diversity of lemurs includes over 100 species spread across the diverse ecoregions of Madagascar. The late Pleistocene and Holocene subfossil record from Madagascar expands this diversity to include 17 extinct species, all larger than any extant lemur species. Numerous studies have explored this diversity by focusing on variation in life-history strategies in lemurs and other strepsirrhines, comparing them to haplorhine primates. In general, strepsirrhines gestate, wean, and reach sexual maturity more rapidly than haplorhines, but differences in relative brain size, body size, and ecology complicate these comparisons. Megaladapis madagascariensis is an extinct, large bodied (~46 kg) folivorous lemur that can provide an important point of reference in these studies, but early phases of M. madagascariensis ontogeny are necessary to develop these comparisons. Here, we describe a complete juvenile cranium of M. madagascariensis from Anjohibe cave in northern Madagascar. The specimen preserves the complete deciduous premolar row. MicroCT scans reveal the developing paracones of the canine, P2, and P3 are present in the crypts between the roots of the deciduous dentition. The crypt of M1 is preserved, though the crown is absent and the M1 alveoli are not fully developed. Using growth rate data collected from M. edwardsi dentition, the state of dental development in this specimen of M. madagascariensis suggests that it was less than one year-old at time of death. The entire cranium is about 55% the total length of an adult cranium from Anjohibe cave. As expected in such an immature individual, the rostrum is relatively short, post-orbital constriction is limited, and the nuchal crest is relatively small compared to the adult. This specimen also preserves an intact braincase, facilitating comparisons between the juvenile and adult endocasts from Megaladapis and extant lemurs at comparable developmental stages. Overall, the juvenile cranium supports previous observations that – adjusted for its large body mass – Megaladapis life history was consistent with the relatively accelerated life-history of other strepsirrhines. These observations provide important context and model parameters for exploring the impact of the very recent extinction of Megaladapis and other large bodied lemurs in Madagascar. 

The evolutionary journey of primates is complex, as lineages disperse between continents and adapt to new ecosystems. The fossil collection at the Duke Lemur Center (DLC) is well positioned to tell this story using primate specimens from the Paleogene of North America and Africa, and the Neogene of Africa, South America, and Madagascar. Founded in 1977, the collection was primarily only accessible – and interpretable – to specialized researchers. Visitors and students unfamiliar with fragmentary fossils and obscure taxonomy faced the daunting task of keeping track of the primate journey while following staff through cabinets and drawers. This contrasted with significant education and outreach efforts at the DLC’s main campus, where noninvasive research on the colony of over 200 living lemurs was accessible to the public through tours, interpretive exhibits, and classroom outreach. Our goal was to work together with the DLC education team to fabricate an exhibit that helped visitors access our Big Idea: Humans and Lemurs Share an Evolutionary History That Spans the Globe. The exhibit space is relatively small and the taxa and time periods are unfamiliar to most visitors. We designed color-coding and symbols that are consistent throughout the exhibit and collection spaces to create a layered experience for visitors. A visit can focus on primate adaptations, ecological niches, plate tectonics, or the geological timescale – all science curriculum goals for different grade levels in North Carolina. The exhibit is also physically layered, with modern primate diversity at eye-level accompanied by infographics that summarize the anatomical distinctions between major clades. Displayed below modern specimens are fossil specimens, demonstrating how fossils are used to understand modern biodiversity and vice versa. This structure is disrupted in the Madagascar section, where subfossil lemur taxa are displayed alongside osteological specimens, emphasizing the recent extinction of Malagasy megafauna. This reinforces the DLC’s larger mission to understand and conserve remaining biodiversity. Exhibit materials were designed with the explicit goal of making them available for collaboration with international partners. The team trained volunteer docents to help visitors access the space, and the exhibit opened to visitors in May 2023. Visitors can provide feedback through a standardized form so we can evaluate exhibit materials and revise them in response to engagement. 

With most ungulates absent from Africa until the Miocene, the morphologically diverse hyraxes were a major component of the Eocene-Oligocene community at Quarry L-41 (~34 Ma) in the Fayum Depression, Egypt. However, their foraging strategies are poorly understood. This study focuses on four extinct hyraxes: Thyrohyrax meyeri, Thyrohyrax litholagus, and Megalohyrax eocaneus, all expected to be grazers; and Saghatherium bowni, previously described as a browser. Mesowear can place extinct herbivores on a spectrum from grazer to browser based on the abrasiveness oftheir lifetime diets. Crown height, tooth length, and cusp angle were measured for the first lower molars (M1) in these four hyrax species. Specimens were categorized into Wear Classes (WC), which correspond with developmental age. WC ranged from 1, first adult molar fully erupted, to 8, all molars extremely worn with significant dentin exposure. Change in mean crown height and cusp angle across different wear classes was not significantly different. Nonetheless, apparent trends suggest compositional differences in diet. Change in mean crown height for Saghertherium indicates that it incorporated more graze than browse because M1 wear occurred in earlier WCs and increased throughout life. In contrast, less wear for WC 1 through 4 in Thyrohyrax indicates that it incorporated more browse. This agrees with recently collected carbon isotope data, which suggests that Saghatherium’s diet included more graze than Thyrohyrax’s. These data are consistent with the description ofThyrohyrax as an arboreal browser. The change in mean crown height for Megalohyrax also suggests a less abrasive diet, although sample size for Megalohyrax was smaller. The browse-biased diet for Megalohyrax is surprising, as isotope values suggest a more open environment. Browsing in salt-stressed environments, forest canopies or forest edges could explain these combined data. Megalohyrax could have foraged in a wider variety of environments than the other taxa because its larger size enabled a wider range. By reconstructing the diets and niche partitioning among morphologically diverse hyraxes at L-41, we hope to gain insights about the ecosystem represented by L-41 near the Eocene-Oligocene Boundary (EOB). This locality represents a time of ecological dynamism when many mammalian communities were dramatically restructured, though the impact of the EOB on African mammal communities remains poorly understood. 

Abstract Diverse lines of geological and geochemical evidence indicate that the Eocene-Oligocene transition (EOT) marked the onset of a global cooling phase, rapid growth of the Antarctic ice sheet, and a worldwide drop in sea level. Paleontologists have established that shifts in mammalian community structure in Europe and Asia were broadly coincident with these events, but the potential impact of early Oligocene climate change on the mammalian communities of Afro-Arabia has long been unclear. Here we employ dated phylogenies of multiple endemic Afro-Arabian mammal clades (anomaluroid and hystricognath rodents, anthropoid and strepsirrhine primates, and carnivorous hyaenodonts) to investigate lineage diversification and loss since the early Eocene. These analyses provide evidence for widespread mammalian extinction in the early Oligocene of Afro-Arabia, with almost two-thirds of peak late Eocene diversity lost in these clades by ~30 Ma. Using homology-free dental topographic metrics, we further demonstrate that the loss of Afro-Arabian rodent and primate lineages was associated with a major reduction in molar occlusal topographic disparity, suggesting a correlated loss of dietary diversity. These results raise new questions about the relative importance of global versus local influences in shaping the evolutionary trajectories of Afro-Arabia’s endemic mammals during the Oligocene. 

Abstract Zoos and natural history museums are both collections-based institutions with important missions in biodiversity research and education. Animals in zoos are a repository and living record of the world's biodiversity, whereas natural history museums are a permanent historical record of snapshots of biodiversity in time. Surprisingly, despite significant overlap in institutional missions, formal partnerships between these institution types are infrequent. Life history information, pedigrees, and medical records maintained at zoos should be seen as complementary to historical records of morphology, genetics, and distribution kept at museums. Through examining both institution types, we synthesize the benefits and challenges of cross-institutional exchanges and propose actions to increase the dialog between zoos and museums. With a growing recognition of the importance of collections to the advancement of scientific research and discovery, a transformational impact could be made with long-term investments in connecting the institutions that are caretakers of living and preserved animals.