Health monitoring and medicinal plant use by bonobos at LuiKotale in the Democratic Republic of the Congo

Infectious diseases are a major threat to the survival and fitness of all great ape species. Because of their close genetic relatedness, great apes share human susceptibility to a variety of viral, bacterial and parasitic infections. In the context of a growing human population and increasing habitat encroachment, pathogen transmission is of great concern for both humans and great apes. Therefore, monitoring great ape health status is key to understanding pathogen-host dynamics. Here, I studied two communities of habituated bonobos (Pan paniscus) at the LuiKotale field site in the Democratic Republic of the Congo (DRC) between December 2018 and July 2020. I first looked at health impairments and how they influence feeding behaviour and food choice in bonobos. I then investigated the consumption of Manniophyton fulvum leaves and stem bark by bonobos, and its association with parasite presence in faeces. Lastly, I measured individual urinary neopterin levels as a marker for the activation of cellular immunity, and studied how urinary neopterin varied with season, individual age, sex, reproductive status, and the presence of visual sickness symptoms. I found the presence of health impairments predicted neither a change in feeding behaviour nor an increased consumption of medicinal plant candidates. I hypothesized that bonobos used medicinal plant candidates as prophylaxis rather than cures. The consumption of M. fulvum leaves and stem bark was not associated with the presence of strongyle worms and cestode proglottids in faeces. My results suggest alternative triggers of the consumption of M. fulvum, including intestinal pain and discomfort. Finally, I found urinary neopterin levels increased with the presence of respiratory symptoms and fluctuated over a one-year period. I discussed the possible link to malaria and other infectious diseases in bonobo’s neopterin variation. This study highlights the extent of medicinal plant use by bonobos at LuiKotale and sheds light on ecoimmunological aspects of the species. Further research is needed to understand the nature of diseases and infections carried by and affecting bonobos in order to better understand how individuals use medicinal plant candidates to maintain and restore health in the wild

Optically trapped Feshbach molecules of fermionic 161Dy and 40K

We report on the preparation of a pure ultracold sample of bosonic DyK Feshbach molecules, which are composed of the fermionic isotopes 161Dy and 40K. Employing a magnetic sweep across a resonance located near 7.3 G, we produce up to 5000 molecules at a temperature of about 50 nK. For purification from the remaining atoms, we apply a Stern-Gerlach technique based on magnetic levitation of the molecules in a very weak optical dipole trap. With the trapped molecules we finally reach a high phase-space density of about 0.1. We measure the magnetic field dependence of the molecular binding energy and the magnetic moment, refining our knowledge of the resonance parameters. We also demonstrate a peculiar anisotropic expansion effect observed when the molecules are released from the trap and expand freely in the magnetic levitation field. Moreover, we identify an important lifetime limitation that is imposed by the 1064-nm infrared trap light itself and not by inelastic collisions. The light-induced decay rate is found to be proportional to the trap light intensity and the closed-channel fraction of the Feshbach molecule. These observations suggest a one-photon coupling to electronically excited states to limit the lifetime and point to the prospect of loss suppression by optimizing the wavelength of the trapping light. Our results represent important insights and experimental steps on the way to achieve quantum-degenerate samples of DyK molecules and novel superfluids based on mass-imbalanced fermion mixtures

What fecal analyses reveal about Manniophyton fulvum consumption in LuiKotale bonobos (Pan paniscus): A medicinal plant revisited

Observations of animals in the wild can result in the discovery of plants for human medicinal purposes. In this context, our closest relatives, the great apes, are of particular interest. The Euphorbiaceae Manniophyton fulvum possesses both phytochemical and biomechanical properties. Its use in the genus Pan (P. troglodytes; P. paniscus) is thought to be based on its mechanical properties promoting the egestion of intestinal parasites, but additional observations from different habitats where the behavior is performed may shed more light on its true purpose. To improve our understanding of what triggers this behavior, we investigated M. fulvum consumption in wild bonobos at LuiKotale, Democratic Republic of the Congo between December 2018 and July 2020. Specifically, we tested the hypothesis that M. fulvum ingestion is related to gastro-intestinal parasite expulsion. Of 649 focal follows of 37 individuals from two habituated communities, consumption of M. fulvum was observed on 111 days (N = 507), independent of seasons, environmental factors and the plant's availability. A total of 588 fecal samples were assessed for the presence/absence of gastro-intestinal parasites. We found strongyle eggs in 2.89% of samples and their presence was not associated with the ingestion of M. fulvum or environmental conditions. We discuss the importance of seasonality in the life cycle of strongyle species that may influence the pattern of M. fulvum consumption observed at LuiKotale. Our data open additional perspectives concerning behavioral parameters such as the existence of a cultural component when comparing ingestion behavior between communities

First report of a leopard (Panthera pardus)-bonobo (Pan paniscus) encounter at the LuiKotale study site, Democratic Republic of the Congo

Predation is a major cause of mortality in non-human primates, and considered a selective force in the evolution of primate societies. Although larger body size is considered as protection against predation, evidence for predation on great apes by carnivores comes from chimpanzees (Pan troglodytes), gorillas (Gorilla gorilla), and orangutans (Pongo spp.). Here, we describe the first encounter between wild bonobos (Pan paniscus) and a leopard (Panthera pardus). A single leopard was confronted by a group of habituated bonobos for three hours. Two adult males and one adolescent female bonobo actively harassed the leopard, which remained still for most of the encounter and reacted only to close approaches by bonobos. While no predation was observed, their behaviours confirm that bonobos perceive leopards as potential predators. Our report adds novel information to descriptions from other African ape species, and sheds light on the behavioural repertoire of bonobos’ anti-predation strategies. For future investigations, we suggest tagging leopards to remotely monitor their movements and allow assessment of encounter rates as one of several factors influencing predation pressure

Bumble Bees (Bombus spp) along a Gradient of Increasing Urbanization

BACKGROUND: Bumble bees and other wild bees are important pollinators of wild flowers and several cultivated crop plants, and have declined in diversity and abundance during the last decades. The main cause of the decline is believed to be habitat destruction and fragmentation associated with urbanization and agricultural intensification. Urbanization is a process that involves dramatic and persistent changes of the landscape, increasing the amount of built-up areas while decreasing the amount of green areas. However, urban green areas can also provide suitable alternative habitats for wild bees. METHODOLOGY/PRINCIPAL FINDINGS: We studied bumble bees in allotment gardens, i.e. intensively managed flower rich green areas, along a gradient of urbanization from the inner city of Stockholm towards more rural (periurban) areas. Keeping habitat quality similar along the urbanization gradient allowed us to separate the effect of landscape change (e.g. proportion impervious surface) from variation in habitat quality. Bumble bee diversity (after rarefaction to 25 individuals) decreased with increasing urbanization, from around eight species on sites in more rural areas to between five and six species in urban allotment gardens. Bumble bee abundance and species composition were most affected by qualities related to the management of the allotment areas, such as local flower abundance. The variability in bumble bee visits between allotment gardens was higher in an urban than in a periurban context, particularly among small and long-tongued bumble bee species. CONCLUSIONS/SIGNIFICANCE: Our results suggest that allotment gardens and other urban green areas can serve as important alternatives to natural habitats for many bumble bee species, but that the surrounding urban landscape influences how many species that will be present. The higher variability in abundance of certain species in the most urban areas may indicate a weaker reliability of the ecosystem service pollination in areas strongly influenced by human activity

Quantitative Historical Change in Bumblebee (Bombus spp.) Assemblages of Red Clover Fields

Flower visiting insects provide a vitally important pollination service for many crops and wild plants. Recent decline of pollinating insects due to anthropogenic modification of habitats and climate, in particular from 1950's onwards, is a major and widespread concern. However, few studies document the extent of declines in species diversity, and no studies have previously quantified local abundance declines. We here make a quantitative assessment of recent historical changes in bumblebee assemblages by comparing contemporary and historical survey data. species observed in the 1930's, five species were not observed at present. The latter were all long-tongued, late-emerging species.Because bumblebees are important pollinators, historical changes in local bumblebee assemblages are expected to severely affect plant reproduction, in particular long-tubed species, which are pollinated by long-tongued bumblebees

Performance studies of the CMS strip tracker before installation

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