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Leaf and fruit species eaten (%) by 10 adult chimpanzees at Kanyawara, Kibale National Park, Uganda, over 17 focal sample periods (June–December 2008) vs. proportion of leaf and fruit species identified in their fecal samples (N = 81). Shaded area denotes focal sample periods during wet season, between two drier periods.
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Ascertaining the full range of dietary constituents of a primate population allows the identification of habitats with important food resources and can assist efforts to conserve primates. For unhabituated populations, we can acquire otherwise unobtainable dietary information from macroscopic inspection of fecal samples. This method has made a sign...
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Examining the diets of primate populations inhabiting different habitat types could be useful in understanding local adaptation and divergence between these populations. In Cameroon, the Nigeria–Cameroon chimpanzee (Pan troglodytes ellioti) is subdivided into two genetically distinct populations that occupy different habitat types; one occurs in fo...
Citations
... For invertebrate contents, all identified matter were those of insects, so hereafter we refer to them as insect to clarify that we did not detect non-insect invertebrates. We did not identify the vertebrate remains to species level, recording skin, bone, and hair in the samples as 'vertebrates' (Phillips & McGrew 2013). Regarding insects and vertebrates, it is often the case that their bodies make up less than 5% of fecal volume. ...
... In this study, we used fecal analysis to reveal the diet of chimpanzees. Some limitations of this method are well established (McGrew et al. 2009;Phillips & McGrew 2013;Moore et al. 2017), with vegetative foods (pith, leaf, stem) and flowers typically not identifiable and thus not accurately represented in comprehensive food lists (Tutin & Fernandez 1993b). Consequently, our results are likely to have underestimated plant food diversity. ...
Characterizing the diet of wild chimpanzees is fundamental to understanding ecological variation, flexibility, and adaptation within and among populations. Here, we describe the diet composition of central chimpanzees (Pan troglodytes troglodytes) in Moukalaba-Doudou National Park, southwestern Gabon. The chimpanzee diet in this area has not previously been described. Based on a macroanalysis of 809 fecal samples and 1,119 minutes of direct observation of their foraging, we showed that they consume fewer insects and more vertebrate prey than those in other study sites. No evidence for the consumption of termites or driver ants was found. Fruits of Ficus spp. was the most frequently identified plant food and appeared in the diet of Moukalaba chimpanzees throughout the year. Chimpanzees at Moukalaba, like at other study sites, exhibit a preference for a small number of fruit species, including Ficus spp., among the foods available at any given period or area while flexibly changing the foods they eat in response to seasonal changes in fruit quantity in the habitat.
... Metabarcoding is perhaps the most efficient technique for describing the arthropod feeding ecology of this primate species, compared to for example, direct observations and items remaining in the scats 38,39,68 . Nevertheless, this method still has some disadvantages [69][70][71] . ...
Primates are very selective in the foods they include in their diets with foraging strategies that respond to spatial and temporal changes in resource availability, distribution and quality. Colombian woolly monkeys ( Lagothrix lagotricha lugens ), one of the largest primate species in the Americas, feed mainly on fruits, but they also eat a high percentage of arthropods. This differs from closely related Atelid species that supplement their diet with leaves. In an 11 month study, we investigated the foraging strategies of this endemic monkey and assessed how resource availability affects dietary selection. Using behavioural, phenological, arthropod sampling and metabarcoding methods, we recorded respectively foraging time, forest productivity, arthropod availability in the forest and arthropod consumption. Scat samples and capturing canopy substrates (i.e. moss, bromeliads, aerial insects) were used for assigning arthropod taxonomy. The most important resource in the diet was fruits (54%), followed by arthropods (28%). Resource availability predicted feeding time for arthropods but not for fruits. Further, there was a positive relationship between feeding time on fruits and arthropods, suggesting that eating both resources during the same periods might work as an optimal strategy to maximize nutrient intake. Woolly monkeys preferred and avoided some fruit and arthropod items available in their home range, choosing a wide variety of arthropods. Geometrid moths (Lepidoptera) were the most important and consistent insects eaten over time. We found no differences in the type of arthropods adults and juveniles ate, but adults invested more time foraging for this resource, especially in moss. Although woolly monkeys are generalist foragers, they do not select their food items randomly or opportunistically.
... En la ecología, la identificación de semillas de excrementos de animales, encontradas en el suelo o transportados por humanos, puede proporcionar información sobre las relaciones ecológicas o posibles amenazas para la conservación. Aunque las técnicas moleculares se utilizan cada vez más, la identificación macroscópica de semillas sigue siendo una herramienta vital en la ecología (Phillips & McGrew, 2013;Srivathsan et al., 2015). Dicha identificación solo es posible gracias a la existencia de colecciones de referencia adecuadas en bancos de semillas y herbarios. ...
Las semillas pueden ser pequeñas e ignoradas por un observador casual, pero ejercen fuerzas poderosas. Regeneran ecosistemas enteros y soportan redes alimenticias complejas. Han sido refinados por la selección natural para incrementar la supervivencia de las plantas y la persistencia de sus genes en el espacio y en el tiempo (Cain et al., 2000). Las semillas no actúan solas, sino que reclutan fuerzas abióticas o de origen animal para ayudarlos a moverse. Las tortugas gigantes, las iguanas de tierra y las aves transportan las semillas de muchas especies a través del paisaje de Galápagos (Blake et al., 2012; Traveset et al., 2016), actividad que ha ayudado a restaurar y mantener poblaciones clave de cactus (Gibbs et al., 2008). El hecho de que estas interacciones semilla-animal también puedan ser adoptadas por especies invasoras (Blake et al., 2015) simplemente refuerza su importancia en la reproducción exitosa de las plantas. Este es el contexto ecológico dentro del cual las semillas cumplen su misión de regeneración. Para comprender el papel de las semillas en la reproducción de las plantas, necesitamos primero conocer la fisiología de la germinación y la latencia de las semillas. Conocer la estructura básica de semillas y frutos también nos dará una idea de cómo interactúan las plantas con sus agentes de dispersión al moverse a través del espacio hasta lugares en donde crece la próxima generación de plantas. Esta guía introduce la estructura de semillas y frutos dentro del contexto ecológico de la biología de dispersión.
... In ecology, the identification of seeds in animal droppings, on the ground, or transported by humans, can provide insight into ecological relations or conservation threats. Although molecular techniques are increasingly used, macroscopic identification of seeds remains a vital tool in ecology (Phillips & McGrew, 2013;Srivathsan et al., 2015). Such identification is only possible if there are appropriate reference collections available, usually maintained by seed banks and herbaria. ...
Seeds may be small and overlooked by a casual observer, but they exert powerful forces. They regenerate whole ecosystems and support complex food webs. They have been refined by natural selection to increase the persistence of plants and their genes over time and space (Cain et al., 2000). Seeds do not act alone, but rather enlist abiotic forces or animals to help them move. Giant tortoises and iguanas carry the seeds of many species across the Galapagos landscape (Blake et al., 2012; Traveset et al., 2016), an activity that has helped restore and maintain keystone populations of cactus (Gibbs et al., 2008). The fact that these seed-animal interactions can be co-opted by invasive species (Blake et al., 2015) merely reinforces their importance in successful plant reproduction. This is the ecological context within which seeds accomplish their mission of regeneration. To understand the role of seeds in plant reproduction, we need to understand the physiology of seed germination and dormancy. Knowing the basic structure of seeds and fruits will also give us an insight into how plants interact with dispersal vectors as they move through the environment to places where they can originate the next generation of plants. This guide introduces seed and fruit structure within the ecological context of dispersal biology.
... The use of fecal analysis is an inexpensive and noninvasive method of investigating the diet of terrestrial vertebrates (Litvaitis 2000). Seeds and fruits can be easily extracted from fecal material and identified macroscopically (McGrew et al. 2009, Phillips andMcGrew 2013). However, identification of smaller, sometimes microscopic, vegetation fragments remaining after mastication and digestion depends on the ability to identify epidermal features including cuticle, stomata, cell walls, glands, trichomes, silica cells, druses, crystals, starch grains, and general cellular configurations distinctive to a taxon (Storr 1961, Litvaitis 2000. ...
We developed a simple and environmentally‐friendly protocol for identifying herbivore diets by isolating and identifying microscopic vegetation fragments from fecal materials that can be easily applied in remote areas where laboratories are absent. We used feces from human‐habituated Virunga mountain gorillas (Gorilla beringei beringei), whose diet is well‐known, to develop and validate the protocol. First, fresh materials from parts of the 5 most frequently consumed plants by the Virunga gorillas were collected from June to July, 2016, processed, and their distinctive features photographed using a digital microscope to establish a plant reference collection. Second, we collected fresh fecal samples from 16 known gorillas and successfully identified distinctive vegetation fragments of the 5 key food plants. The method is inexpensive, environmentally friendly, and does not require sophisticated laboratory equipment. It has the potential to be applied to species that cannot be easily studied by direct observation and those ranging in remote regions. The method can also be used in other studies involving plant‐animal interactions, the ontogeny of feeding behavior, and animal ecology. © 2020 The Wildlife Society. Dietary studies of unhabituated herbivores living in remote areas present special challenges. We developed an environmentally‐friendly protocol for isolating and identifying vegetative fragments from fecal material of herbivores. We successfully validated the protocol using human habituated Virunga mountain gorillas with known diets.
... Therefore we used systematic fecal analysis to describe their diet (McGrew, Marchant, & Phillips, 2009). Although fruit and insect residues are often identifiable in feces, macroscopic fecal analysis is less useful for assessing nonfruit plants eaten because foliage items like leaves and piths are rarely identifiable taxonomically (Phillips & McGrew, 2013). ...
Behavioral flexibility, including an ability to modify feeding behavior, is a key trait enabling primates to survive in forest fragments. In human‐dominated landscapes, unprotected forest fragments can become progressively degraded, and may be cleared entirely, challenging the capacity of primates to adjust to the changes. We examined responses of wild chimpanzees (Pan troglodytes schweinfurthii) to major habitat change: that is, clearance of forest fragments for agriculture. Over 7 years, fragments in Bulindi, Uganda, were reduced in size by 80%. We compared the chimpanzees’ diet at the start and end of this period of rapid deforestation, using data derived mainly from fecal analysis. Similar to other long‐term study populations, chimpanzees in Bulindi have a diverse diet comprising over 169 plant foods. However, extensive deforestation seemed to impact their feeding ecology. Dietary changes after fragment clearance included reduced overall frugivory, reduced intake of figs (Ficus spp.; formerly a dietary “staple” for these chimpanzees), and reduced variety of fruits in fecal samples. Nevertheless, the magnitude of most changes was remarkably minor given the extent of forest loss. Agricultural fruits increased in dietary importance, with crops accounting for a greater proportion of fruits in fecal samples after deforestation. In particular, cultivated jackfruit (Artocarpus heterophyllus) became a “staple” food for the chimpanzees but was scarcely eaten before fragment clearance. Crops offer some nutritional benefits for primates, being high in carbohydrate energy and low in hard‐to‐digest fiber. Thus, crop feeding may have offset foraging costs associated with loss of wild foods and reduced overall frugivory for the chimpanzees. The adaptability of many primates offers hope for their conservation in fragmented, rural landscapes. However, long‐term data are needed to establish whether potential benefits (i.e. energetic, reproductive) of foraging in agricultural matrix habitats outweigh fitness costs from anthropogenic mortality risk for chimpanzees and other adaptable primates. Two adult males of the Bulindi chimpanzee community sharing a large cultivated jackfruit (Artocarpus heterophyllus) (Photo by Jacqueline Rohen). Chimpanzees in Bulindi experienced 80% forest loss in 7 years Chimpanzees adapted to fragment clearance by eating more agricultural crops, especially jackfruit Long‐term data are needed to establish if crop foraging benefits in matrix habitats outweigh costs (i.e., anthropogenic mortality risk) Chimpanzees in Bulindi experienced 80% forest loss in 7 years Chimpanzees adapted to fragment clearance by eating more agricultural crops, especially jackfruit Long‐term data are needed to establish if crop foraging benefits in matrix habitats outweigh costs (i.e., anthropogenic mortality risk)
... The study provided no discussion or explanation as to why this was the case, but it could be argued that the digestibility of young leaves may account for the difference. Research comparing the number of plant or animal items detected from focal observations and macroscopic fecal inspection in Kibale National Park, Uganda concluded that the indirect method was less accurate in describing folivorous and faunivorous diet types (Phillips and McGrew 2013). The difference here was likely due to the difficulties of identifying leaf, pith, or animal fragments in the fecal samples (Tutin and Fernandez 1993;Phillips and McGrew 2013). ...
... Research comparing the number of plant or animal items detected from focal observations and macroscopic fecal inspection in Kibale National Park, Uganda concluded that the indirect method was less accurate in describing folivorous and faunivorous diet types (Phillips and McGrew 2013). The difference here was likely due to the difficulties of identifying leaf, pith, or animal fragments in the fecal samples (Tutin and Fernandez 1993;Phillips and McGrew 2013). This research also indicated that when analyzing fecal samples in two subsets, one considering gut passage rates and the other not, the results were similar (Phillips and McGrew 2013). ...
... The difference here was likely due to the difficulties of identifying leaf, pith, or animal fragments in the fecal samples (Tutin and Fernandez 1993;Phillips and McGrew 2013). This research also indicated that when analyzing fecal samples in two subsets, one considering gut passage rates and the other not, the results were similar (Phillips and McGrew 2013). However, the study did not examine the time spent feeding on different food types. ...
Both observational and indirect evidence are widely used to determine the diets of wild animals. Direct observations are often assumed to provide the most comprehensive reflection of diet, but many wild animals are logistically challenging to observe. Despite the regular use of observational and indirect methods for inferring diet in wild animals, they have rarely been compared in detail for the same study population. Over 12 months this study assessed the congruence of methods in estimating the diet of a montane community of eastern chimpanzees Pan troglodytes schweinfurthii in Nyungwe National Park, Rwanda using observational scan samples and macroscopic fecal inspection. The assessment of the number of food species consumed each month was comparable between methods, but the estimation of the composition of items in the diet differed significantly. Most notably, the fecal samples significantly underestimated the consumption of flowers, and certain fruit species, which based on direct behavioural observations were seasonally consumed at very high rates. Conversely, direct observations underestimated the consumption of leaves and pith in comparison to results present in the fecal samples. These results suggest that combining methods where possible is most useful for accurate monitoring of dietary trends, particularly for species that experience significant seasonal shifts in their diet.
... Based on Phillips and McGrew (2013) we expected to identify around 80% of the species 133 from which fruit had been eaten, but only around 20% from which leaves had been eaten, 134 and 60% of species overall in the faecal samples, due to the difficulty of identifying non-135 frugivory dietary parts at species level (Phillips and McGrew, 2013). We expected the 136 proportional abundance of seeds of a species in the faecal samples to increase the longer 137 we observed the chimpanzees to feed on that species. ...
... Based on Phillips and McGrew (2013) we expected to identify around 80% of the species 133 from which fruit had been eaten, but only around 20% from which leaves had been eaten, 134 and 60% of species overall in the faecal samples, due to the difficulty of identifying non-135 frugivory dietary parts at species level (Phillips and McGrew, 2013). We expected the 136 proportional abundance of seeds of a species in the faecal samples to increase the longer 137 we observed the chimpanzees to feed on that species. ...
... We defined a feeding event as "item placed into mouth, remaining there (or parts thereof) 236 and seen to be either chewed or swallowed" (Phillips and McGrew, 2013). We identified the 237 plant species being eaten (Observed Feeding Plant) with the help of an experienced 238 ...
Some East African chimpanzee ( Pan troglodytes schweinfurthii ) communities, such as the Sonso chimpanzees, display an unusually limited range of tool-use, but it remains unclear whether this is due to ecological and/or cultural factors. Information on ecological conditions and the diet of the Sonso chimpanzees in relation to neighbouring communities is needed. Here, we studied three adjacent communities in Budongo Forest (Sonso, Waibira, and Kamira), and the presumed core area of an undescribed community (Mwera), in the neighbouring Bugoma Forest. Through line-transects, we investigated (i) whether there were differences in food diversity and abundance between the communities’ home ranges; (ii) whether the home ranges differed in abundance of sticks and insect nests; and (iii) whether Sonso and Mwera chimpanzees differed in their diet (using faecal samples). Across communities, Sonso had the richest food availability and the lowest insect nest abundance. However, food availability in Mwera, Bugoma, was richer than Budongo communities that neighbour the Sonso territory, suggesting that there may be variation within Budongo. Data from faecal samples replicated our direct observations of food availability suggesting that Sonso chimpanzees had a broader diet than Mwera chimpanzees. This difference in foods availability may partially explain the Sonso chimpanzees’ lack of stick-tool-use, and low levels of insectivory. The tool repertoire of the other communities is currently unknown; however, we make predictions based on our ecological data. More detailed knowledge of small-scale variation in ecology within and between forest habitats may be important to advancing our understanding of the drivers of tool-use.
SIGNIFICANCE STATEMENT – HIGHLIGHTED STUDENT PAPER
To advance our knowledge of the role of ecological factors in the emergence of tool use in chimpanzees, a nuanced understanding of the ecological conditions different chimpanzee communities experience is needed. We studied four Ugandan chimpanzee communities in two forests. One of these communities, Sonso, in the Budongo Forest, is well-known for its restricted range of tool types, including a total absence of stick use. Food diversity and abundance were highest, and stick tool use opportunities (abundance of sticks and insect nests) were lowest for the core-habitat of the Sonso chimpanzees in contrast to the other communities. We argue that ecological factors play a role in their unusual pattern of tool use, and make predictions about the expected types of tool use in the other communities based on their ecology. Thus, our study provides information that may help advance our understanding of how tool use arises under varied socioecological circumstances.
... Food items that have been thoroughly masticated or digested by herbivores (e.g., leaves) may be unrecognizable in faecal matter (Phillips and Mcgrew, 2013), compared to indigestible items. However, by surviving both mastication and digestion, phytoliths have proved to be good indicators of a full dietary repertoire of species ingested by the consumers (Phillips and Lancelotti, 2014). ...
Phytoliths are silica casts of plant cells, created within and between living tissues across almost all plant clades.
Because they are abundant, durable and distinctive, phytoliths are used to deduce historic vegetation patterns and
human uses across the fields of archeology, paleoethnobotany, paleoecology, and historical ecology, particularly at
sites where preservation of larger plant-derived samples is poor. Nonetheless, phytolith research has recently
contributed to advances in biogeochemical cycling and carbon sequestration. Although much progress has been made
over the past few decades, some basic methodological concerns in phytolith systematics and Si cycling still hamper
the overall development of this emerging field of science. Here, we first review basic scenarios of phytolith studies
across different disciplines of science and then advocate interdisciplinary phytolith research to overcome the
challenges of phytolith systematics, inform the representation of Si and C cycling in biogeochemical models, and
improve the utility of phytoliths as proxies in archeology and paleontology.
... Studies on modern animals have demonstrated that delicate food remains are underrepresented in faeces, while more resistant objects have the opposite pattern [34]. Thus, we cannot exclude that other food sources such as softer prey and plant fragments, which are not found in the coprolites, formed at least parts of the diet of the coprolite producer. ...
Diets of extinct animals can be difficult to analyse if no direct evidence, such as gut contents, is preserved in association with body fossils. Inclusions from coprolites (fossil faeces), however, may also reflect the diet of the host animal and become especially informative if the coprolite producer link can be established. Here we describe, based on propagation phase-contrast synchrotron microtomography (PPC-SRμCT), the contents of five morphologically similar coprolites collected from two fossil-bearing intervals from the highly fossiliferous Upper Triassic locality at Krasiejów in Silesia, Poland. Beetle remains, mostly elytra, and unidentified exoskeleton fragments of arthropods are the most conspicuous inclusions found in the coprolites. The abundance of these inclusions suggests that the coprolite producer deliberately targeted beetles and similar small terrestrial invertebrates as prey, but the relatively large size of the coprolites shows that it was not itself a small animal. The best candidate from the body fossil record of the locality is the dinosauriform Silesaurus opolensis Dzik, 2003, which had an anatomy in several ways similar to those of bird-like neotheropod dinosaurs and modern birds. We hypothesize that the beak-like jaws of S. opolensis were used to efficiently peck small insects off the ground, a feeding behaviour analogous to some extant birds.
