Historical dietary ecology of the Yellow-backed Duiker traces dietary change across the 20th century

Dental microwear texture analysis (DMTA) is a versatile tool used to infer diet across an array of animal species. It has been used to explore differences in diet across species, habitat, climate, and both historical and deep time. This study sought to explore the historical dietary ecology of the Yellow-backed Duiker Cephalophus silvicultor to assess how their diet has changed over time, in this near-threatened species. We used DMTA of C. silvicultor from across the 20th century, as well as that from other African bovids including two species of duiker (Philantomba monticola and Sylvicapra grimmia) to reconstruct dietary ecology. Additionally, we ran these data through principal component and quadratic discriminant analysis to create a model to predict foraging ecology. The results show significant increases in complexity and decreases in anisotropy over time, as well as significant differences between cephalophines of the same size or guild. Our model was also very effective at correctly classifying individuals within their observed guild. Notably, our sample of duikers exhibited significant differences in dental microwear despite phylogenetic similarity. This further supports DMTA more strongly reflecting ecological behavior rather than phylogeny. Additionally, the increase in complexity and decrease in anisotropy are consistent with a greater contribution of hard or brittle foods and/or reduced consumption of tough foods over time by Yellow-backed duikers. These patterns may reflect changes in resource use, habitat loss, hunting pressure, or other ecological factors, hinting at potential responses of animals to anthropogenic stresses in the future.Author summary: Diet plays a central role in how animals interact with their environments and respond to ecological change. As climate change, habitat loss, and overhunting continue to reshape ecosystems, understanding how species adapt their feeding behavior has become increasingly important for conservation efforts. Here we used dental microwear texture analysis (DMTA) to examine dietary patterns in more than a dozen species of African bovids. We focused primarily on the Yellow-backed Duiker (Cephalophus silvicultor) a large forest antelope that is currently in decline due to anthropogenic impacts. We found evidence of increasing dental microwear complexity and decreasing anisotropy over the course of the 20th century, a pattern consistent with greater consumption of hard or brittle foods and/or fewer mechanically tough foods. These changes may reflect shifts in feeding ecology, but the specific underlying ecological mechanisms cannot be determined from DMTA alone. In addition, we developed a statistical model that accurately predicts an animal’s foraging guild from dental microwear. We also constructed a model that accurately predicts foraging guild based on dental microwear. This model may help researchers reconstruct the diets and ecological roles of rare, historical, or extinct mammals when direct observations are impossible. Our study demonstrates how dental microwear can reveal long-term ecological change and improve our understanding of how mammals respond to rapidly changing environments.