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Abstract Mammalian megafauna have been critical to the functioning of Earth’s biosphere for millions of years. However, since the Plio-Pleistocene, their biodiversity has declined concurrently with dramatic environmental change and hominin evolution. While these biodiversity declines are well-documented, their implications for the ecological function of megafaunal communities remain uncertain. Here, we adapt ecometric methods to evaluate whether the functional link between communities of herbivorous, eastern African megafauna and their environments (i.e., functional trait-environment relationships) was disrupted as biodiversity losses occurred over the past 7.4 Ma. Herbivore taxonomic and functional diversity began to decline during the Pliocene as open grassland habitats emerged, persisted, and expanded. In the mid-Pleistocene, grassland expansion intensified, and climates became more variable and arid. It was then that phylogenetic diversity declined, and the trait-environment relationships of herbivore communities shifted significantly. Our results divulge the varying implications of different losses in megafaunal biodiversity. Only the losses that occurred since the mid-Pleistocene were coincident with a disturbance to community ecological function. Prior diversity losses, conversely, occurred as the megafaunal species and trait pool narrowed towards those adapted to grassland environments.more » « less
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Abstract AimWe investigate locomotor function in artiodactyls, represented by calcaneal gear ratio, as it relates to multiple environments. Using an ecometric approach, we develop a trait–environment model to investigate ecosystem‐level changes through time and to reconstruct past environments. We apply the trait–environment model to a case study of six sites in Kenya to evaluate changes over the past 100 years. LocationGlobal. MethodsLocomotor morphology was represented by calcaneal gear ratios measured as the overall length of a calcaneum divided by length of its in‐lever, that is calcaneal tuber. We collected calcaneal gear ratio measurements from skeletal specimens of 157 artiodactyl species in museum collections and used species’ spatial distributions to determine the composition of 47,420 communities globally. For 21,827 communities with three or more species of artiodactyls, we used maximum likelihood to model ecometric relationships between community‐level locomotor morphology and five environmental variables, including mean annual temperature, annual precipitation, elevation, vegetation cover and ecoregion province. ResultsCommunity mean gear ratios range from 1.43 to 1.56 (µ = 1.50). Mean gear ratios are highest in the tropical regions and lowest in the mid‐latitudes. Variance in mean calcaneal gear ratio is related to ecoregion division (68.6%), vegetation cover (63.5%) and precipitation (60.7%). In a case study of Kenyan sites, we demonstrate habitat homogenization patterns that match mammal community turnover patterns. Main conclusionsWith this ecometric framework, fossils of artiodactyl post‐crania can be used to assist in interpreting past ecoregion, vegetation cover and precipitation for a more comprehensive understanding of palaeoenvironment. These relationships between functional traits and environment will enable better models of biotic responses for conservation of functional diversity under changing environments.more » « less
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An understanding of science concepts is important for living in modern society. Supporting adults’ science learning can be particularly challenging because most adults no longer attend formal educational institutions where access and opportunities are facilitated by teachers and school-sponsored programs. Biological field stations (BFSs) are a newly recognized educational venue that hold considerable intrinsic value for adult science education. In this study, we conducted a survey of 223 U.S. BFSs about their nonformal and informal educational outreach programs for adults. Results show BFSs offer a wide variety of science learning programs for adults, focused heavily on experiential learning to engage learners. These experiences promote interactions with the natural environment and are perceived to increase participants’ knowledge and skills. This study has implications for how adult educators can better support the professional development of science educators at BFSs and enrich the general public's science learning.more » « less
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Llewellyn, Donald A. (Ed.)Peer writing groups serve an important role in providing a venue to improve written productivity, provide support, and brainstorm research ideas. Peer accountability assists with focusing attention on tasks at hand, which often receive less attention due to the demands on agent’s and researcher's time. Establishing dedicated meeting times to prioritize writing and editing improves time management, writing efficiency, research progression, and overall productivity. For extension agents and researchers, these components are essential for completing daily tasks and career advancement. Interdisciplinary writing groups also help broaden the scope of expertise, provide professional development experiences, and support the land grant mission.more » « less
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null (Ed.)Abstract Biological field stations (BFSs) are well positioned through their informal STEM (science, technology, engineering, and mathematics) education programs to improve levels of science literacy and support environmental sustainability. A survey of 223 US BFSs revealed that their outreach programs strive to promote conservation and environmental stewardship in addition to disseminating place-based knowledge and/or skills. In this article, we unpack the educational approaches that BFSs use to engage learners, the aspects of science literacy most often addressed, and the perceived learning outcomes. Most notably, the BFSs reported that their participants develop an interest in and excitement for science, increase or change their knowledge of program topics, identify more with the scientific enterprise, and engage in scientific practices. The results indicate opportunities for BFSs to conduct more rigorous assessments of participant learning and program impact. By focusing on learner engagement, science learning, and participant outcomes, BFSs and other place-based informal education venues can expand their efforts and better support conservation and science learning.more » « less
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null (Ed.)A paleontological deposit near San Clemente de Térapa represents one of the very few Rancholabrean North American Land Mammal Age sites within Sonora, Mexico. During that time, grasslands were common, and the climate included cooler and drier summers and wetter winters than currently experienced in northern Mexico. Here, we demonstrate restructuring in the mammalian community associated with environmental change over the past 40,000 years at Térapa. The fossil community has a similar number of carnivores and herbivores whereas the modern community consists mostly of carnivores. There was also a 97% decrease in mean body size (from 289 kg to 9 kg) because of the loss of megafauna. We further provide an updated review of ungulates and carnivores, recognizing two distinct morphotypes of Equus, including E. scotti and a slighter species; as well as Platygonus compressus; Camelops hesternus; Canis dirus; and Lynx rufus; and the first regional records of Palaeolama mirifica, Procyon lotor, and Smilodon cf. S. fatalis. The Térapa mammals presented here provide a more comprehensive understanding of the faunal community restructuring that occurred in northern Mexico from the late Pleistocene to present day, indicating further potential biodiversity loss with continued warming and drying of the region.more » « less
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null (Ed.)Informal learning institutions (ILIs) create opportunities to increase public understanding of science and promote increased inclusion of groups underrepresented in Science, Technology, Engineering, and Math (STEM) careers but are not equally distributed across the United States. We explore geographic gaps in the ILI landscape and identify three groups of underserved counties based on the interaction between population density and poverty percentage. Among ILIs, National Park Service lands, biological field stations, and marine laboratories occur in areas with the fewest sites for informal learning opportunities and have the greatest potential to reach underserved populations, particularly in rural or high poverty counties. Most counties that are underserved by ILIs occur in the Great Plains, the southeast, and the northwest. Furthermore, these counties have higher Indigenous populations who are underrepresented in STEM careers. These unexpected geographic gaps represent opportunities for investments in ILI offerings through collaborations and expansion of existing resources.more » « less
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