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This work focuses on the nesting behavior of the West African chimpanzee (Pan troglodytes verus) in the anthropized habitats of the village of Tikankali and its surroundings. Studies on chimpanzee nesting behavior are carried out at several sites of Senegal but never in Tikankaly. Thus, proximity with the Niokolo Koba National Park and the presence of a gold mining industry mean that data on chimpanzee nesting behavior and anthropogenic impacts in their habitats for decisions-making about chimpanzee conservation in this area. We recorded a total of 213 chimpanzee nests during two surveys over a distance of 47.81 km (i.e., 47.81 km x 2). Data were collected in October 2020 and October 2021. The majority of nests (63%) were found in wooded savannah, 19% in bamboo savannah, 09% in gallery forest and 07% in open forest. The results showed that 22 plant species belonging to 08 families are used for chimpanzee nests in and around Tikankali. However, half of the nests were in Pterocarpus erinaceus (53%); followed by Hexalobus monopetalus (8%); Diospyros mespiliformis (6%), Piliostigma thonningii (6%), Lannea acida (6%); and Grewia bicolor (4%). The average height of trees used as chimpanzee nest supports was 9.88 m (SD=3.60) and the average height of nests was 7.46 m (SD=3.23). Linear regression analysis (r=0.84; N=213; p< 0.05) suggested a preference for nesting at a particular height but also that nest height is a function of the supporting tree's height. The current study contributes to the knowledge of chimpanzee nesting behavior in Tikankali, the anthropogenic disruption and will help in the implementation of a good chimpanzee management and conservation strategy in Senegal. [ABSTRACT FROM AUTHOR]

Simple Summary: The aim of protected areas is to conserve nature. However, the wild animal populations they shelter are not immune to extinction. It is, therefore, important for researchers to provide regular information on the ecology of these populations in order to guide management actions and enhance knowledge. From studies based on chimpanzee nests, we revealed that chimpanzees in Niokolo Koba National Park nest more in closed habitats than in open ones, and that certain plant species are preferentially chosen for nest construction. Diospyros mespiliformis and Pterocarpus erinaceus are the trees most used by chimpanzees for bearing their nests. In addition, we found that chimpanzee nest height and nest life were influenced by the environmental factors. We conclude that the preservation of nesting sites of chimpanzees is crucial for the conservation of this great ape, considered to be on the border of extinction in Senegal. The Niokolo Koba National Park (NKNP) is the largest protected area in Senegal and lies at the northern limit of the chimpanzee's range in West Africa. Recent information on nesting behavior and factors influencing nesting behavior is available for several sites outside NKNP. However, the information available for NKNP is obsolete. Considering that the adequate management of chimpanzee populations cannot be achieved without strong scientific knowledge, it is essential to update data on chimpanzee, Pan troglodytes verus, nesting behavior in NKNP. For this reason, we surveyed their habitat in Mt. Assirik and recorded 626 chimpanzee nests. The results of the study showed that chimpanzees nest more often in closed-canopy habitats such as gallery forests. The average nest height observed in this study was 8.07 ± 0.36 m, varying between 2 and 20 m, which is well below the heights described in most sites where chimpanzees cohabit with large carnivores. Botanical surveys confirmed that chimpanzees select tree species bearing their nests. In Assirik, 12 of the 37 tree species bearing nests are the most used. The nest decay rate (or the time it takes for a nest to go from the fresh to the skeletal stage) at Assirik averaged 68.8 ± 5.8 days. [ABSTRACT FROM AUTHOR]

Objectives: To understand the function of food sharing among our early hominin ancestors, we can turn to our nonhuman primate relatives for insight. Here, we examined the function of meat sharing by Fongoli chimpanzees, a community of western chimpanzees (Pan troglodytes verus) in southeastern Sénégal. Materials and Methods: We tested three non‐mutually exclusive hypotheses that have been used to explain patterns of food sharing: kin selection, generalized reciprocity, and meat‐for‐mating opportunities. We analyzed meat sharing events (n = 484) resulting from hunts, along with data on copulations, age‐sex class, and kinship to determine which variables predict the likelihood of meat sharing during this study period (2006–2019). Results: We found full or partial support for kin selection, direct reciprocity, and meat‐for‐mating‐opportunities. However, the analyses reveal that reciprocity and a mother/offspring relationship were the strongest predictors of whether or not an individual shared meat. Conclusions: The results of this study emphasize the complexity of chimpanzee meat sharing behaviors, especially at a site where social tolerance offers increased opportunities for meat sharing by individuals other than dominant males. These findings can be placed in a referential model to inform hypotheses about the sensitivity of food sharing to environmental pressures, such as resource scarcity in savanna landscapes. [ABSTRACT FROM AUTHOR]

Few-shot learning (FSL) describes the challenge of learning a new task using a minimum amount of labeled data, and we have observed significant progress made in this area. In this paper, we explore the effectiveness of the FSL theory by considering a real-world problem where labels are hard to obtain. To assist a large study on chimpanzee hunting activities, we aim to classify various animal species that appear in our in-the-wild camera traps located in Senegal. Using the philosophy of FSL, we aim to train an FSL network to learn to separate animal species using large public datasets and implement the network on our data with its novel species/classes and unseen environments, needing only to label a few images per new species. Here, we first discuss constraints and challenges caused by having in-the-wild uncurated data, which are often not addressed in benchmark FSL datasets. Considering these new challenges, we create two experiments and corresponding evaluation metrics to determine a network's usefulness in a real-world implementation scenario. We then compare results from various FSL networks, and describe how factors may affect a network's potential real-world usefulness. We consider network design factors such as distance metrics or extra pre-training, and examine their roles in a real-world implementation setting. We also consider additional factors such as support set selection and ease of implementation, which are usually ignored when a benchmark dataset has been established. [ABSTRACT FROM AUTHOR]

The ultrastructure of the mature spermatozoa of Tergestia clonacantha and T. laticollis collected from the digestive tracts of fishes from New Caledonia is described using transmission electron microscopy and compared to that of related species. The spermatozoa of the two species exhibit the general pattern described in most digeneans, namely two axonemes with the 9 + “1” pattern of the Trepaxonemata, nucleus, mitochondrion, cortical microtubules, an external ornamentation of the plasma membrane, spine-like bodies and granules of glycogen. The spermatozoa of T. clonacantha and T. laticollis show the same ultrastructural model with some specificities in each case, particularly in the disposition of the structures in the posterior extremities of the spermatozoon. This study confirms that ultrastructural characters of the mature spermatozoon are useful tools for the phylogenetic analysis of the Digenea.

New liquid–liquid equilibrium data of ternary systems of mono ethylene glycol + n‐pentane + methanol, mono‐ethylene glycol (MEG) + n‐pentane + ethanol, and mono ethylene glycol + n‐pentane + n‐butanol from 283.15 to 293 K are presented in this work. Binodal curves were obtained by the cloud point titration method. Tie‐line compositions were obtained through density and sound velocity measurements of phases in equilibrium. Results show that the solubility increases with temperature in all systems and decreases as the alcohol chain increases. The relative solubility data indicate that the alcohols are more soluble in MEG than in n‐C5. The obtained experimental data were successfully correlated using the CPA and the PC‐SAFT equation with appropriate binary interaction parameters. [ABSTRACT FROM AUTHOR]