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Abstract In 1967 G.G. Simpson described three partial mandibles from early Miocene deposits in Kenya that he interpreted as belonging to a new strepsirrhine primate,Propotto. This interpretation was quickly challenged, with the assertion thatPropottowas not a primate, but rather a pteropodid fruit bat. The latter interpretation has not been questioned for almost half a century. Here we re-evaluate the affinities ofPropotto, drawing upon diverse lines of evidence to establish that this strange mammal is a strepsirrhine primate as originally suggested by Simpson. Moreover, our phylogenetic analyses support the recognition ofPropotto, together with late EocenePlesiopithecusfrom Egypt, as African stem chiromyiform lemurs that are exclusively related to the extant aye-aye (Daubentonia) from Madagascar. Our results challenge the long-held view that all lemurs are descended from a single ancient colonization of Madagascar, and present an intriguing alternative scenario in which two lemur lineages dispersed from Africa to Madagascar independently, possibly during the later Cenozoic.
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The Epic Journey of Primates: Building a New Exhibit and Tour at the Duke Lemur Center Museum of Natural History
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.
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- Award ID(s):
- 2023087
- PAR ID:
- 10523477
- Publisher / Repository:
- Society of Vertebrate Paleontology
- Date Published:
- Subject(s) / Keyword(s):
- Outreach Exhibit General Public Fossil Primate Evolution
- Format(s):
- Medium: X
- Location:
- Annual Meeting of the Society of Vertebrate Paleontology in Cincinnati, Ohio
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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