Abstract
Dental wear analyses have been widely used to interpret the dietary ecology in primates. However, it remains unclear to what extent a combination of wear analyses acting at distinct temporal scales can be beneficial in interpreting the tooth use of primates with a high variation in their intraspecific dietary ecology. Here, we combine macroscopic tooth wear (occlusal fingerprint analysis, long-term signals) with microscopic 3D surface textures (short-term signals) exploring the tooth use of a historical western chimpanzee population from northeastern Liberia with no detailed dietary records. We compare our results to previously published tooth wear and feeding data of the extant and continually monitored chimpanzees of Taї National Park in Ivory Coast. Macroscopic tooth wear results from molar wear facets of the Liberian population indicate only slightly less wear when compared to the Taї population. This suggests similar long-term feeding behavior between both populations. In contrast, 3D surface texture results show that Liberian chimpanzees have many and small microscopic wear facet features that group them with those Taї chimpanzees that knowingly died during dry periods. This coincides with historical accounts, which indicate that local tribes poached and butchered the Liberian specimens during dust-rich dry periods. In addition, Liberian females and males differ somewhat in their 3D surface textures, with females having more microscopic peaks, smaller hill and dale areas and slightly rougher wear facet surfaces than males. This suggests a higher consumption of insects in Liberian females compared to males, based on similar 3D surface texture patterns previously reported for Taї chimpanzees. Our study opens new options for uncovering details of feeding behaviors of chimpanzees and other living and fossil primates, with macroscopic tooth wear tracing the long-term dietary and environmental history of a single population and microscopic tooth wear addressing short-term changes (e.g. seasonality).
Highlights
The diet of chimpanzees (Pan troglodytes) is highly variable, and includes fruits, leaves and other vegetative plant parts as well as animal resources [e.g. 1–5]
The occlusal fingerprint analysis (OFA) results reveal that both populations differ to some extent in their macroscopic wear pattern; the angle of facet inclination shows a trend towards steeper phase II wear facets and smaller phase II wear facet areas in the Liberian population of chimpanzees compared to Taï chimpanzees (Fig 2, Table 1)
When testing for presence of a seasonality signal, using Factor Analysis (FA) with two factors we found that the 3D surface texture (3DST) of the Liberian upper and lower M1s and M2s overlap with those individuals of the Taï chimpanzees that died during the dry period but are significantly different from those that died during the rainy period (Fig 3, Table 2)
Summary
The diet of chimpanzees (Pan troglodytes) is highly variable, and includes fruits, leaves and other vegetative plant parts as well as animal resources [e.g. 1–5]. Verus) communities of the population from the Taї National Park (Ivory Coast) [12]. Both communities feed mainly on fruits and other plant parts, but with varying number of plant species. Female chimpanzees engage more in nut cracking than males [1, 15], and they more often consume insects while males consume more meat from hunted vertebrates [13, 16] Environmental factors such as grit and dust have a strong effect on the feeding ecology of chimpanzees. Western chimpanzees of the Taї National Park are recurrently exposed to large amounts of wind-borne dust particles during specific dry periods of the year affecting their chewing and digestive efficiency [13]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
