1
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Goldsborough Z, Crofoot MC, Barrett BJ. Male-biased stone tool use by wild white-faced capuchins (Cebus capucinus imitator). Am J Primatol 2024; 86:e23594. [PMID: 38196199 DOI: 10.1002/ajp.23594] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 12/13/2023] [Accepted: 12/27/2023] [Indexed: 01/11/2024]
Abstract
Tool-using primates often show sex differences in both the frequency and efficiency of tool use. In species with sex-biased dispersal, such within-group variation likely shapes patterns of cultural transmission of tool-use traditions between groups. On the Panamanian islands of Jicarón and Coiba, a population of white-faced capuchins (Cebus capucinus imitator)-some of which engage in habitual stone tool use-provide an opportunity to test hypotheses about why such sex-biases arise. On Jicarón, we have only observed males engaging in stone tool use, whereas on Coiba, both sexes are known to use tools. Using 5 years of camera trap data, we provide evidence that this variation likely reflects a sex difference in tool use rather than a sampling artifact, and then test hypotheses about the factors driving this pattern. Differences in physical ability or risk-aversion, and competition over access to anvils do not account for the sex-differences in tool-use we observe. Our data show that adult females are physically capable of stone tool use: adult females on Coiba and juveniles on Jicarón smaller than adult females regularly engage in tool use. Females also have ample opportunity to use tools: the sexes are equally terrestrial, and competition over anvils is low. Finally, females rarely scrounge on left-over food items either during or after tool-using events, suggesting they are not being provisioned by males. Although it remains unclear why adult white-faced capuchin females on Jicarón do not use stone-tools, our results illustrate that such sex biases in socially learned behaviors can arise even in the absence of obvious physical, environmental, and social constraints. This suggests that a much more nuanced understanding of the differences in social structure, diet, and dispersal patterns are needed to explain why sex-biases in tool use arise in some populations but not in others.
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Affiliation(s)
- Zoë Goldsborough
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany
- Department of Biology, University of Konstanz, Konstanz, Germany
- Center for the Advanced Study of Collective Behavior, University of Konstanz, Konstanz, Germany
- Smithsonian Tropical Research Institute, Ancon, Panama
| | - Margaret C Crofoot
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany
- Department of Biology, University of Konstanz, Konstanz, Germany
- Center for the Advanced Study of Collective Behavior, University of Konstanz, Konstanz, Germany
- Smithsonian Tropical Research Institute, Ancon, Panama
| | - Brendan J Barrett
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany
- Department of Biology, University of Konstanz, Konstanz, Germany
- Center for the Advanced Study of Collective Behavior, University of Konstanz, Konstanz, Germany
- Smithsonian Tropical Research Institute, Ancon, Panama
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2
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Ndiaye YH, Ndiaye PI, Lindshield SM, Pruetz JD. Updating Chimpanzee Nesting Data at Mount Assirik (Niokolo Koba National Park, Senegal): Implications for Conservation. Animals (Basel) 2024; 14:553. [PMID: 38396522 PMCID: PMC10886333 DOI: 10.3390/ani14040553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Revised: 11/12/2023] [Accepted: 01/16/2024] [Indexed: 02/25/2024] Open
Abstract
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.
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Affiliation(s)
- Yaya Hamady Ndiaye
- Département de Biologie Animale, Faculté des Sciences et Techniques, Université Cheikh Anta Diop, Dakar 5005, Senegal;
| | - Papa Ibnou Ndiaye
- Département de Biologie Animale, Faculté des Sciences et Techniques, Université Cheikh Anta Diop, Dakar 5005, Senegal;
- Observatoire International Homme-Milieux Téssékéré, IRL3189 “Environnement, Santé, Sociétés”, Université Cheikh Anta Diop, Dakar 5005, Senegal
| | | | - Jill Daphne Pruetz
- Department of Anthropology, Texas State University, San Marcos, TX 78666, USA;
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3
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Hobaiter C, Klein H, Gruber T. Habitual ground nesting in the Bugoma Forest chimpanzees (Pan troglodytes schweinfurthii), Uganda. Am J Primatol 2024; 86:e23583. [PMID: 38037523 DOI: 10.1002/ajp.23583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 11/05/2023] [Accepted: 11/24/2023] [Indexed: 12/02/2023]
Abstract
We report the presence of habitual ground nesting in a newly studied East African chimpanzee (Pan troglodytes schweinfurthii) population in the Bugoma Central Forest Reserve, Uganda. Across a 2-year period, we encountered 891 night nests, 189 of which were classified as ground nests, a rate of ~21%. We find no preliminary evidence of socio-ecological factors that would promote its use and highlight local factors, such as high incidence of forest disturbance due to poaching and logging, which appear to make its use disadvantageous. While further study is required to establish whether this behavior meets the strict criteria for nonhuman animal culture, we support the argument that the wider use of population and group-specific behavioral repertoires in flagship species, such as chimpanzees, offers a tool to promote the urgent conservation action needed to protect threatened ecosystems, including the Bugoma forest.
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Affiliation(s)
- Catherine Hobaiter
- Wild Minds Lab, School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
- Bugoma Primate Conservation Project, Bugoma Central Forest Reserve, Hoima, Uganda
| | - Harmonie Klein
- Wild Minds Lab, School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK
| | - Thibaud Gruber
- Bugoma Primate Conservation Project, Bugoma Central Forest Reserve, Hoima, Uganda
- Faculty of Psychology and Educational Sciences and Swiss Center for Affective Sciences, University of Geneva, Geneva, Switzerland
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4
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Whittaker BA, Nolet-Mulholland L, Nevoit A, Yun D, Lambert CT, Blunk SC, Guillette LM. Zebra finches have style: Nest morphology is repeatable and associated with experience. iScience 2023; 26:108194. [PMID: 37965145 PMCID: PMC10641255 DOI: 10.1016/j.isci.2023.108194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2023] [Revised: 07/17/2023] [Accepted: 10/10/2023] [Indexed: 11/16/2023] Open
Abstract
We investigated whether birds build nests in repeatable styles and, if so, whether styles were associated with past nest-building experience. Laboratory, captive bred zebra finches in an Experimental group were given nest-building experience, whereas, birds in a Control group were not. Each pair (n = 20) then built four nests that underwent image analyses for nest size, geometric shape and entrance orientation. Birds built nests in repeatable styles, with lower morphometric variation among nests built by the same pair and higher morphometric variation among nests built by different pairs. Morphology was not associated with construction time, body weight, nor age of birds. We found lower morphometric variation among nests built by the Experimental group, which also used less material to build nests compared to the Control group. Prior experience may therefore have been advantageous, as learning to reduce material usage while achieving a similar product (nest) may have lowered building costs.
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Affiliation(s)
| | | | - Anna Nevoit
- Department of Psychology, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Deborah Yun
- Department of Psychology, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Connor T. Lambert
- Department of Psychology, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Sara C. Blunk
- Department of Psychology, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Lauren M. Guillette
- Department of Psychology, University of Alberta, Edmonton, AB T6G 2R3, Canada
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5
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Tédonzong LRD, Ndju'u MBM, Tchamba M, Angwafo TE, Lens L, Tagg N, Willie J. The influence of vegetation structure on sleeping site selection by chimpanzees (Pan troglodytes troglodytes). Am J Primatol 2023:e23505. [PMID: 37157167 DOI: 10.1002/ajp.23505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 04/17/2023] [Accepted: 04/29/2023] [Indexed: 05/10/2023]
Abstract
Sleep is an important aspect of great ape life; these animals build sleeping platforms every night. In a community of chimpanzees, each subgroup selects a sleeping site where each individual builds a sleeping platform, mostly on a tree. Previous studies have measured the heights of sleeping platforms and sleeping trees to test the predation avoidance and thermoregulation hypotheses of sleeping site selection. However, it remains unclear how components of vegetation structure (vertical and horizontal) together determine the selection of sleeping sites by chimpanzees. Using botanical inventories around sleeping sites in a tropical rainforest of Cameroon, we found that chimpanzees preferentially sleep in trees measuring 40-50 cm in diameter. Regarding height, on average, sleeping trees measured 26 m and sleeping platforms were built at 16 m. To build sleeping platforms, chimpanzees preferred four tree species, which represent less than 3% of tree species in the study area. We demonstrate that the variation in abundance of tree species and the vertical and horizontal structure of the vegetation drive chimpanzee sleeping site selection. It was previously thought that preference for vegetation types was the driver of sleeping site selection in chimpanzees. However, results from this study indicate that the importance of vegetation types in sleeping site selection depends on their botanical characteristics including the variation in tree size, the abundance of all trees, the abundance of sleeping trees, and the occurrence of preferred sleeping tree species, which predict sleeping site selection. The height and diameter of trees are considered by chimpanzees when selecting a particular tree for sleeping and when selecting a site with a specific vertical structure. In addition to tree height, the abundance of smaller neighboring trees may also play a role in the chimpanzee antipredation strategy. Our results demonstrate that chimpanzees consider several vegetation parameters to establish sleeping sites.
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Affiliation(s)
- Luc Roscelin Dongmo Tédonzong
- Projet Grands Singes (PGS), Yaoundé, Cameroon
- Centre for Research and Conservation (CRC), Royal Zoological Society of Antwerp (RZSA), Antwerp, Belgium
- Section on Great Apes, Primate Specialist Group, IUCN Species Survival Commission, Yaoundé, Cameroon
| | | | - Martin Tchamba
- Department of Forestry, University of Dschang, Dschang, Cameroon
| | | | - Luc Lens
- Department of Biology, Ghent University (UGent), Ghent, Belgium
| | - Nikki Tagg
- Projet Grands Singes (PGS), Yaoundé, Cameroon
- Centre for Research and Conservation (CRC), Royal Zoological Society of Antwerp (RZSA), Antwerp, Belgium
| | - Jacob Willie
- Projet Grands Singes (PGS), Yaoundé, Cameroon
- Centre for Research and Conservation (CRC), Royal Zoological Society of Antwerp (RZSA), Antwerp, Belgium
- Department of Biology, Ghent University (UGent), Ghent, Belgium
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6
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Mbouombouo Mfossa D, Abwe EE, Whytock RC, Morgan BJ, Huynen M, Beudels‐Jamar RC, Brotcorne F, Tchouamo RI. Distribution, habitat use and human disturbance of gorillas (
Gorilla gorilla
) in the Ebo forest, Littoral Region, Cameroon. Afr J Ecol 2022. [DOI: 10.1111/aje.13052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Ekwoge Enang Abwe
- Ebo Forest Research Project Douala Cameroon
- San Diego Zoo Wildlife Alliance San Diego California USA
| | - Robin Cameron Whytock
- Ebo Forest Research Project Douala Cameroon
- Faculty of Natural Sciences The University of Stirling Scotland UK
| | - Bethan J. Morgan
- Ebo Forest Research Project Douala Cameroon
- San Diego Zoo Wildlife Alliance San Diego California USA
- Faculty of Natural Sciences The University of Stirling Scotland UK
| | | | | | | | - Roger Isaac Tchouamo
- ERAIFT The University of Kinshasa, DRC Kinshasa DRC
- The University of Dschang Dschang Cameroon
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7
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Giuliano C, Stewart FA, Piel AK. Chimpanzee (Pan troglodytes schweinfurthii) grouping patterns in an open and dry savanna landscape, Issa Valley, western Tanzania. J Hum Evol 2022; 163:103137. [DOI: 10.1016/j.jhevol.2021.103137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 12/09/2021] [Accepted: 12/14/2021] [Indexed: 11/25/2022]
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8
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Fei H, de Guinea M, Yang L, Chapman CA, Fan P. Where to sleep next? Evidence for spatial memory associated with sleeping sites in Skywalker gibbons (Hoolock tianxing). Anim Cogn 2022; 25:891-903. [PMID: 35099623 DOI: 10.1007/s10071-022-01600-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 01/11/2022] [Accepted: 01/13/2022] [Indexed: 12/29/2022]
Abstract
Finding suitable sleeping sites is highly advantageous but challenging for wild animals. While suitable sleeping sites provide protection against predators and enhance sleep quality, these sites are heterogeneously distributed in space. Thus, animals may generate memories associated with suitable sleeping sites to be able to approach them efficiently when needed. Here, we examined traveling trajectories (i.e., direction, linearity, and speed of traveling) in relation to sleeping sites to assess whether Skywalker gibbons (Hoolock tianxing) use spatial memory to locate sleeping trees. Our results show that about 30% of the sleeping trees were efficiently revisited by gibbons and the recursive use of trees was higher than a randomly simulated visiting pattern. When gibbons left the last feeding tree for the day, they traveled in a linear fashion to sleeping sites out-of-sight (> 40 m away), and linearity of travel to sleeping trees out-of-sight was higher than 0.800 for all individuals. The speed of the traveling trajectories to sleeping sites out-of-sight increased not only as sunset approached, but also when daily rainfall increased. These results suggest that gibbons likely optimized their trajectories to reach sleeping sites under increasing conditions of predatory risk (i.e., nocturnal predators) and uncomfortable weather. Our study provides novel evidence on the use of spatial memory to locate sleeping sites through analyses of movement patterns, which adds to an already extensive body of literature linking cognitive processes and sleeping patterns in human and non-human animals.
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Affiliation(s)
- Hanlan Fei
- Department of Ecology, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, China.,College of Life Science, China West Normal University, Nanchong, 637002, China
| | - Miguel de Guinea
- Movement Ecology Laboratory, Department of Ecology Evolution and Behavior, Alexander Silverman Institute of Life Science, The Hebrew University of Jerusalem, 91904, Jerusalem, Israel
| | - Li Yang
- Department of Ecology, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Colin A Chapman
- Wilson Center, 1300 Pennsylvania Avenue NW, Washington, DC, 20004, USA.,Department of Anthropology, The George Washington University, Washington, DC, 20037, USA.,School of Life Sciences, University of KwaZulu-Natal, Scottsville, Pietermaritzburg, 3209, South Africa.,Shaanxi Key Laboratory for Animal Conservation, Northwest University, Xi'an, 710127, China
| | - Pengfei Fan
- Department of Ecology, School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, China.
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9
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Lindshield S, Hernandez-Aguilar RA, Korstjens AH, Marchant LF, Narat V, Ndiaye PI, Ogawa H, Piel AK, Pruetz JD, Stewart FA, van Leeuwen KL, Wessling EG, Yoshikawa M. Chimpanzees (Pan troglodytes) in savanna landscapes. Evol Anthropol 2021; 30:399-420. [PMID: 34542218 DOI: 10.1002/evan.21924] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 12/17/2020] [Accepted: 07/29/2021] [Indexed: 12/22/2022]
Abstract
Chimpanzees (Pan troglodytes) are the only great apes that inhabit hot, dry, and open savannas. We review the environmental pressures of savannas on chimpanzees, such as food and water scarcity, and the evidence for chimpanzees' behavioral responses to these landscapes. In our analysis, savannas were generally associated with low chimpanzee population densities and large home ranges. In addition, thermoregulatory behaviors that likely reduce hyperthermia risk, such as cave use, were frequently observed in the hottest and driest savanna landscapes. We hypothesize that such responses are evidence of a "savanna landscape effect" in chimpanzees and offer pathways for future research to understand its evolutionary processes and mechanisms. We conclude by discussing the significance of research on savanna chimpanzees to modeling the evolution of early hominin traits and informing conservation programs for these endangered apes.
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Affiliation(s)
- Stacy Lindshield
- Department of Anthropology, Purdue University, West Lafayette, Indiana, USA
| | - R Adriana Hernandez-Aguilar
- Department of Social Psychology and Quantitative Psychology, Faculty of Psychology, University of Barcelona, Barcelona, Spain.,Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Amanda H Korstjens
- Life and Environmental Sciences Department, Bournemouth University, Talbot Campus, Poole, UK
| | | | - Victor Narat
- CNRS/MNHN/Paris Diderot, UMR 7206 Eco-anthropology, Paris, France
| | - Papa Ibnou Ndiaye
- Département de Biologie Animale, Faculté des Sciences et Techniques, Université Cheikh Anta Diop de Dakar, Dakar, Senegal
| | - Hideshi Ogawa
- School of International Liberal Studies, Chukyo University, Toyota, Aichi, Japan
| | - Alex K Piel
- Department of Anthropology, University College London, London, UK
| | - Jill D Pruetz
- Department of Anthropology, Texas State University, San Marcos, Texas, USA
| | - Fiona A Stewart
- Department of Anthropology, University College London, London, UK.,School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, UK
| | - Kelly L van Leeuwen
- Department of Life and Environmental Sciences, Bournemouth University, Talbot Campus, Poole, UK
| | - Erin G Wessling
- Department of Human Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Midori Yoshikawa
- Department of Zoology, National Museum of Nature and Science, Ibaraki, Tokyo, Japan
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10
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van Dijk K, Cibot M, McLennan MR. Chimpanzees (Pan troglodytes) adapt their nesting behavior after large-scale forest clearance and community decline. Am J Primatol 2021; 83:e23323. [PMID: 34455609 DOI: 10.1002/ajp.23323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2021] [Revised: 07/20/2021] [Accepted: 08/12/2021] [Indexed: 11/12/2022]
Abstract
Chimpanzees (Pan troglodytes) build nests at night for sleeping and occasionally during daytime for resting. Over the course of seven years, forest fragments in Bulindi, Uganda, were reduced in size by about 80% when landowners converted forest to agricultural land. However, unlike other studies on nesting behavior in response to habitat disturbance, chimpanzees at Bulindi had no opportunity to retreat into nearby undisturbed forest. To understand behavioral adaptations to forest clearance, we compared Bulindi chimpanzees' nesting characteristics before and after this period of major deforestation. After deforestation, chimpanzees built nests at lower heights in shorter trees, and reused a larger proportion of their nests. Additionally, average nest group size increased after deforestation, even though community size declined by approximately 20% over the same period. The substantial decrease in available forest habitat may have caused the chimpanzees to aggregate for nesting. However, more cohesive nesting may also have been influenced by dietary shifts (increased reliance on agricultural crops) and a need for enhanced safety with increased human encroachment. Conversely, the chimpanzees selected similar tree species for nesting after deforestation, apparently reflecting a strong preference for particular species, nested less often in exotic species, and built integrated nests (constructed using multiple trees) at a similar frequency as before fragment clearance. Chimpanzees living in unprotected habitat in Uganda, as at Bulindi, face mounting anthropogenic pressures that threaten their survival. Nevertheless, our study shows that chimpanzees can adjust their nesting behavior flexibly in response to rapid, extensive habitat change. While behavioral flexibility may enable them to cope with deforestation, at least to a certain point, the long-term survival of chimpanzees in fast-changing human-modified landscapes requires intensive conservation efforts.
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Affiliation(s)
- Kim van Dijk
- Bulindi Chimpanzee and Community Project, Hoima, Uganda.,Animal Behaviour and Cognition, Utrecht University, Utrecht, The Netherlands
| | - Marie Cibot
- Bulindi Chimpanzee and Community Project, Hoima, Uganda.,Anicoon Vétérinaires, Ploemeur, Larmor-Plage, France
| | - Matthew R McLennan
- Bulindi Chimpanzee and Community Project, Hoima, Uganda.,Department of Social Sciences, Faculty of Humanities and Social Sciences, Oxford Brookes University, Oxford, UK.,Centre for Ecology and Conservation, University of Exeter, Cornwall, UK
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11
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Fotang C, Bröring U, Roos C, Enoguanbhor EC, Dutton P, Tédonzong LRD, Willie J, Yuh YG, Birkhofer K. Environmental and anthropogenic effects on the nesting patterns of Nigeria-Cameroon chimpanzees in North-West Cameroon. Am J Primatol 2021; 83:e23312. [PMID: 34343361 DOI: 10.1002/ajp.23312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 07/11/2021] [Accepted: 07/24/2021] [Indexed: 11/09/2022]
Abstract
Environmental conditions and human activity influence the selection of nest sites by chimpanzees and may have serious conservation implications. We examined the characteristics of nesting trees preferred by chimpanzees, investigated the effect of vegetation composition and topography on nest site locations and seasonality on nesting heights of chimpanzees, and verified the effect of predator occurrence and human activity on the nesting behavior of the Nigeria-Cameroon chimpanzee (Pan troglodytes ellioti) in Kom-Wum Forest Reserve (KWFR) and surrounding unprotected forest in Cameroon. We recorded 923 nests, 502 signs of human activity, and 646 nesting trees along line transects and recces (reconnaissance) for two seasons. We found that chimpanzees constructed more arboreal nests on tall primary trees with high lowest branch height and large diameter at breast height. Moreover, they oriented their nests within trees in the slope direction when the nesting trees were located on slopes. Additionally, the occurrence of chimpanzee nests was positively related to increasing elevation and slope and decreased with distance to primary forest. In contrast, the number of nests increased with distance to secondary forest, open land, and villages, and nesting height was not influenced by seasons. While we recorded no signs of large nocturnal chimpanzee predators at nesting trees, we found signs of hunting activity at nesting locations. Nesting high in trees is likely a way of avoiding hunting, while nest orientation within trees in slope direction shortens escape routes from human hunters. Our findings suggest that chimpanzees select safe trees (tall trees with high lowest branch height) located in nesting areas (primary forest, high elevation, and steep slopes) that are not easily accessible by humans. Therefore, conservation efforts should focus on protecting primary forests at high elevation and steep slopes and reducing human impact.
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Affiliation(s)
- Chefor Fotang
- Department of Ecology, Brandenburg University of Technology Cottbus-Senftenberg, Cottbus, Brandenburg, Germany
| | - Udo Bröring
- Department of Ecology, Brandenburg University of Technology Cottbus-Senftenberg, Cottbus, Brandenburg, Germany
| | - Christian Roos
- German Primate Centre Leibniz Institute for Primate Research, Gene Bank of Primates and Primate Genetics, Gottingen, Germany
| | - Evidence C Enoguanbhor
- Department of Geography, Humboldt University of Berlin, Applied Geoinformation Science Laboratory Berlin, Brandenburg, Germany
| | - Paul Dutton
- Independent Researcher, Waikato, New Zealand
| | - Luc R D Tédonzong
- Centre for Research and Conservation (CRC), Royal Zoological Society of Antwerp (RZSA), Antwerp, Belgium
| | - Jacob Willie
- Centre for Research and Conservation (CRC), Royal Zoological Society of Antwerp (RZSA), Antwerp, Belgium.,Department of Biology, Terrestrial Ecology Unit (TEREC), Ghent University (UGent), Ghent, Belgium
| | - Yisa G Yuh
- Hochschule fur nachhaltige Entwicklung Eberswalde, Forestry and Environment, Eberswalde, Germany.,Szkola Glowna Gospodarstwa Wiejskiego, Warszawa, Poland.,Concordia University Montreal, Montreal, Quebec, Canada
| | - Klaus Birkhofer
- Department of Ecology, Brandenburg University of Technology Cottbus-Senftenberg, Cottbus, Brandenburg, Germany
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12
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Corredor-Ospina N, Kreyer M, Rossi G, Hohmann G, Fruth B. First report of a leopard (Panthera pardus)-bonobo (Pan paniscus) encounter at the LuiKotale study site, Democratic Republic of the Congo. Primates 2021; 62:555-562. [PMID: 33950405 PMCID: PMC8225524 DOI: 10.1007/s10329-021-00897-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 02/07/2021] [Indexed: 02/07/2023]
Abstract
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.
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Affiliation(s)
- Nicolas Corredor-Ospina
- LuiKotale Bonobo Project, Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium
- SEC Semillero de Evolución Y Conservación, Universidad Militar Nueva Granada, Cajica, Colombia
| | - Melodie Kreyer
- LuiKotale Bonobo Project, Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium
- Faculty of Science, School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, UK
| | - Giulia Rossi
- LuiKotale Bonobo Project, Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium
| | - Gottfried Hohmann
- Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Barbara Fruth
- LuiKotale Bonobo Project, Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium.
- Faculty of Science, School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, UK.
- Department for the Ecology of Animal Societies, Max Planck Institute for Animal Behavior, Konstanz, Germany.
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13
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Bessone M, Booto L, Santos AR, Kühl HS, Fruth B. No time to rest: How the effects of climate change on nest decay threaten the conservation of apes in the wild. PLoS One 2021; 16:e0252527. [PMID: 34191810 PMCID: PMC8244864 DOI: 10.1371/journal.pone.0252527] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 05/17/2021] [Indexed: 11/18/2022] Open
Abstract
Since 1994, IUCN Red List assessments apply globally acknowledged standards to assess species distribution, abundance and trends. The extinction risk of a species has a major impact on conservation science and international funding mechanisms. Great ape species are listed as Endangered or Critically Endangered. Their populations are often assessed using their unique habit of constructing sleeping platforms, called nests. As nests rather than apes are counted, it is necessary to know the time it takes for nests to disappear to convert nest counts into ape numbers. However, nest decomposition is highly variable across sites and time and the factors involved are poorly understood. Here, we used 1,511 bonobo (Pan paniscus) nests and 15 years of climatic data (2003-2018) from the research site LuiKotale, Democratic Republic of the Congo, to investigate the effects of climate change and behavioural factors on nest decay time, using a Bayesian gamma survival model. We also tested the logistic regression method, a recommended time-efficient option for estimating nest decay time. Our climatic data showed a decreasing trend in precipitation across the 15 years of study. We found bonobo nests to have longer decay times in recent years. While the number of storms was the main factor driving nest decay time, nest construction type and tree species used were also important. We also found evidence for bonobo nesting behaviour being adapted to climatic conditions, namely strengthening the nest structure in response to unpredictable, harsh precipitation. By highlighting methodological caveats, we show that logistic regression is effective in estimating nest decay time under certain conditions. Our study reveals the impact of climate change on nest decay time in a tropical remote area. Failure to account for these changes would invalidate biomonitoring estimates of global significance, and subsequently jeopardize the conservation of great apes in the wild.
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Affiliation(s)
- Mattia Bessone
- School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Lambert Booto
- LuiKotale Bonobo Project, Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium
| | - Antonio R. Santos
- School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Hjalmar S. Kühl
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Barbara Fruth
- School of Biological and Environmental Sciences, Liverpool John Moores University, Liverpool, United Kingdom
- LuiKotale Bonobo Project, Centre for Research and Conservation, Royal Zoological Society of Antwerp, Antwerp, Belgium
- Faculty of Biology/Department of Neurobiology, Ludwig Maximilians University of Munich, Planegg-Martinsried, Germany
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, Germany
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14
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Affiliation(s)
- William C McGrew
- School of Psychology and Neuroscience, University of St Andrews, South Street, Fife, St Andrews, KY16 9AJ, Scotland, UK.
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15
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Something Scary Is Out There: Remembrances of Where the Threat Was Located by Preschool Children and Adults with Nighttime Fear. EVOLUTIONARY PSYCHOLOGICAL SCIENCE 2021. [DOI: 10.1007/s40806-021-00279-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
AbstractYoung children frequently report imaginary scary things in their bedrooms at night. This study examined the remembrances of 140 preschool children and 404 adults selecting either above, side, or below locations for a scary thing relative to their beds. The theoretical framework for this investigation posited that sexual-size dimorphism in Australopithecus afarensis, the presumed human ancestor in the Middle Pliocene, constrained sleeping site choice to mitigate predation. Smaller-bodied females nesting in trees would have anticipated predatory attacks from below, while male nesting on the ground would have anticipated attacks from their side. Such anticipation of nighttime attacks from below is present in many arboreal primates and might still persist as a cognitive relict in humans. In remembrances of nighttime fear, girls and women were predicted to select the below location and males the side location. Following interviews of children and adult questionnaires, multinomial log-linear analyses indicated statistically significant interactions (p < 0.001) of sex by location for the combined sample and each age class driven, in part, by larger frequencies of males selecting the side location and females selecting the below location. Data partitioning further revealed that males selected the side location at larger frequencies (p < 0.001) than the below location, whereas female selection of side and below locations did not differ significantly. While indicative of evolutionary persistence in cognitive appraisal of threat locations, the female hypothesis did not consider natural selection acting on assessment of nighttime terrestrial threats following the advent of early Homo in the Late Pliocene.
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16
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Hernandez-Aguilar RA, Reitan T. Deciding Where to Sleep: Spatial Levels of Nesting Selection in Chimpanzees (Pan troglodytes) Living in Savanna at Issa, Tanzania. INT J PRIMATOL 2020. [DOI: 10.1007/s10764-020-00186-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
AbstractTo understand how animals select resources we need to analyze selection at different spatial levels or scales in the habitat. We investigated which physical characteristics of trees (dimensions and structure, e.g., height, trunk diameter, number of branches) determined nesting selection by chimpanzees (Pan troglodytes) on two different spatial scales: individual nesting trees and nesting sites. We also examined whether individual tree selection explained the landscape pattern of nesting site selection. We compared the physical characteristics of actual (N = 132) and potential (N = 242) nesting trees in nesting sites (in 15 plots of 25 m × 25 m) and of all trees in actual and potential nesting sites (N = 763 in 30 plots of 25 m × 25 m). We collected data in May and June 2003 in Issa, a dry and open savanna habitat in Tanzania. Chimpanzees selected both the site they used for nesting in the landscape and the trees they used to build nests within a nesting site, demonstrating two levels of spatial selection in nesting. Site selection was stronger than individual tree selection. Tree height was the most important variable for both nesting site and tree selection in our study, suggesting that chimpanzees selected both safe sites and secure trees for sleeping.
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17
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Jucá T, Boyle S, Cavalcanti G, Cavalcante T, Tomanek P, Clemente S, de Oliveira T, Barnett AA. Being hunted high and low: do differences in nocturnal sleeping and diurnal resting sites of howler monkeys (Alouatta nigerrima and Alouatta discolor) reflect safety from attack by different types of predator? Biol J Linn Soc Lond 2020. [DOI: 10.1093/biolinnean/blaa102] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Abstract
Predation risk is important in influencing animal behaviour. We investigated how the choice of nocturnal sleeping and diurnal resting sites by two species of primates was influenced by the most likely forms of attack (diurnal raptors and nocturnal felids). We recorded vertical and horizontal patterns of occupancy for 47 sleeping and 31 resting sites, as well as the presence of lianas or vines on trees. We compared the heights of trees used as resting or sleeping sites by the monkeys with those of 200 forest trees that the monkeys did not use. Trees used as nocturnal sleeping sites were taller than those used as diurnal resting sites, and taller than trees that the monkeys did not use. However, while trees used as diurnal resting sites were not significantly taller than non-used trees, diurnal resting sites were located on branches closer to the ground, closer to the main trunk of the tree and in trees with more lianas/vines than nocturnal sleeping sites. The differences in site location can be explained by the type of predator most likely to attack at a particular time: raptors in the day and felids at night.
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Affiliation(s)
- Thays Jucá
- Amazonian Mammals Research Group, National Institute for Amazonian Research (INPA), Manaus, Amazonas, Brazil
| | - Sarah Boyle
- Department of Biology, Rhodes College, Memphis, Tennessee, USA
| | - Gitana Cavalcanti
- Department of Ecology, Conservation and Wildlife Management, Institute of Biological Science, Federal University of Minas Gerais (UFMG), Belo Horizonte, Minas Gerais, Brazil
| | - Thiago Cavalcante
- Amazonian Mammals Research Group, National Institute for Amazonian Research (INPA), Manaus, Amazonas, Brazil
| | - Pavel Tomanek
- Department of Animal Science and Ethology, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences Prague, Prague, Czech Republic
| | - Salatiel Clemente
- Ecology and Natural Resource Management, Federal University of Acre (UFAC), Acre, Brazil
| | - Tadeu de Oliveira
- Department of Biology, Maranhão State University (UEMA), São Luís, Maranhão, Brazil
| | - Adrian A Barnett
- Amazonian Mammals Research Group, National Institute for Amazonian Research (INPA), Manaus, Amazonas, Brazil
- Zoology Department, Amazonas Federal University (UFAM), Manaus, Amazonas, Brazil
- Centre for Research in Evolutionary Anthropology, University of Roehampton, London, UK
- Department of Zoology, Federal University of Pernambuco (UFPE), Recife, Pernambuco, Brazil
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18
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Storks L, Leal M. Sleeping Behavior of the Secretive Puerto Rican Twig Anole, Anolis occultus. CARIBB J SCI 2020. [DOI: 10.18475/cjos.v50i1.a18] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Levi Storks
- Division of Biological Sciences, University of Missouri, Columbia, Missouri, U.S.A
| | - Manuel Leal
- Division of Biological Sciences, University of Missouri, Columbia, Missouri, U.S.A
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19
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Stewart FA, Pruetz JD. Sex Bias and Social Influences on Savanna Chimpanzee (Pan troglodytes verus) Nest Building Behavior. INT J PRIMATOL 2020. [DOI: 10.1007/s10764-020-00157-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
AbstractMany primates show sex differences in behavior, particularly social behavior, but also tool use for extractive foraging. All great apes learn to build a supportive structure for sleep. Whether sex differences exist in building, as in extractive foraging, is unknown, and little is known about how building skills develop and vary between individuals in the wild. We therefore aimed to describe the nesting behavior of savanna chimpanzees (Pan troglodytes verus) in Fongoli, Senegal to provide comparative data and to investigate possible sex or age differences in nest building behaviors and nest characteristics. We followed chimpanzee groups to their night nesting sites to record group (55 nights) and individual level data (17 individuals) on nest building initiation and duration (57 nests) during the dry season between October 2007 and March 2008. We returned the following morning to record nest and tree characteristics (71 nests built by 25 individuals). Fongoli chimpanzees nested later than reported for other great apes, but no sex differences in initiating building emerged. Observations were limited but suggest adult females and immature males to nest higher, in larger trees than adult males, and adult females to take longer to build than either adult or immature males. Smaller females and immature males may avoid predation or access thinner, malleable branches, by nesting higher than adult males. These differences suggest that sex differences described for chimpanzee tool use may extend to nest building, with females investing more time and effort in constructing a safe, warm structure for sleep than males do.
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20
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Nautiyal H, Mathur V, Sinha A, Huffman MA. The Banj oak Quercus leucotrichophora as a potential mitigating factor for human-langur interactions in the Garhwal Himalayas, India: People’s perceptions and ecological importance. Glob Ecol Conserv 2020. [DOI: 10.1016/j.gecco.2020.e00985] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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21
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Same Space, Different Species: The Influence of Exhibit Design on the Expression of Zoo-Housed Apes' Species-Typical Retiring Behaviors. Animals (Basel) 2020; 10:ani10050836. [PMID: 32408572 PMCID: PMC7278436 DOI: 10.3390/ani10050836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 04/28/2020] [Accepted: 04/30/2020] [Indexed: 11/16/2022] Open
Abstract
Wild chimpanzees frequently make arboreal nests, while wild lowland gorillas typically nest on the ground. We aimed to understand whether zoo-housed apes' use of elevated spaces for retiring similarly differed between species and across exhibits. Using a pre-planned exhibit switch at Lincoln Park Zoo (Chicago, USA), we compared where (elevated or terrestrial) two groups of apes (Pan troglodytes and Gorilla gorilla gorilla) performed retiring behaviors (inactive, sleeping, and nest-building behaviors). We studied a group of six chimpanzees and a group of four gorillas in two exhibits of similar size and configuration for two three-month periods (between 3 and 5 p.m.) before and after the groups switched exhibits. We predicted that chimpanzees would be more likely to retire in elevated locations compared to gorillas, irrespective of the exhibit. We found a significant effect of exhibit on where the apes retired but no effect of species, such that both species were more likely to retire in elevated locations in one exhibit but not the other. This suggests that the specific characteristics of the exhibits (e.g., number of visual barriers) influenced the expression of the apes' retiring behaviors. These findings offer further insight in how exhibit design can influence the expression of natural behaviors in these species.
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22
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Tédonzong LRD, Willie J, Makengveu ST, Lens L, Tagg N. Variation in behavioral traits of two frugivorous mammals may lead to differential responses to human disturbance. Ecol Evol 2020; 10:3798-3813. [PMID: 32313637 PMCID: PMC7160177 DOI: 10.1002/ece3.6178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Revised: 02/15/2020] [Accepted: 02/18/2020] [Indexed: 11/28/2022] Open
Abstract
Human activities can lead to a shift in wildlife species' spatial distribution. Understanding the specific effects of human activities on ranging behavior can improve conservation management of wildlife populations in human-dominated landscapes. This study evaluated the effects of forest use by humans on the spatial distribution of mammal species with different behavioral adaptations, using sympatric western lowland gorilla and central chimpanzee as focal species. We collected data on great ape nest locations, ecological and physical variables (habitat distribution, permanent rivers, and topographic data), and anthropogenic variables (distance to trails, villages, and a permanent research site). Here, we show that anthropogenic variables are important predictors of the distribution of wild animals. In the resource model, the distribution of gorilla nests was predicted by nesting habitat distribution, while chimpanzee nests were predicted first by elevation followed by nesting habitat distribution. In the anthropogenic model, the major predictors of gorilla nesting changed to human features, while the major predictors of chimpanzee nesting remained elevation and the availability of their preferred nesting habitats. Animal behavioral traits (body size, terrestrial/arboreal, level of specialization/generalization, and competitive inferiority/superiority) may influence the response of mammals to human activities. Our results suggest that chimpanzees may survive in human-encroached areas whenever the availability of their nesting habitat and preferred fruits can support their population, while a certain level of human activities may threaten gorillas. Consequently, the survival of gorillas in human-dominated landscapes is more at risk than that of chimpanzees. Replicating our research in other sites should permit a systematic evaluation of the influence of human activity on the distribution of mammal populations. As wild animals are increasingly exposed to human disturbance, understanding the resulting consequences of shifting species distributions due to human disturbance on animal population abundance and their long-term survival will be of growing conservation importance.
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Affiliation(s)
- Luc Roscelin Dongmo Tédonzong
- Projet Grands Singes (PGS), CameroonCentre for Research and Conservation (CRC)Royal Zoological Society of Antwerp (RZSA)AntwerpenBelgium
- Terrestrial Ecology Unit (TEREC)Department of BiologyGhent University (UGent)GhentBelgium
- Present address:
Wild Chimpanzee Foundation (WCF)MonroviaLiberia
| | - Jacob Willie
- Projet Grands Singes (PGS), CameroonCentre for Research and Conservation (CRC)Royal Zoological Society of Antwerp (RZSA)AntwerpenBelgium
- Terrestrial Ecology Unit (TEREC)Department of BiologyGhent University (UGent)GhentBelgium
| | - Sandra Tewamba Makengveu
- Projet Grands Singes (PGS), CameroonCentre for Research and Conservation (CRC)Royal Zoological Society of Antwerp (RZSA)AntwerpenBelgium
- Department of ForestryFaculty of Agronomy and Agricultural Sciences (FASA)University of DschangDschangCameroon
| | - Luc Lens
- Terrestrial Ecology Unit (TEREC)Department of BiologyGhent University (UGent)GhentBelgium
| | - Nikki Tagg
- Projet Grands Singes (PGS), CameroonCentre for Research and Conservation (CRC)Royal Zoological Society of Antwerp (RZSA)AntwerpenBelgium
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23
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Comparing Methods for Assessing Chimpanzee (Pan troglodytes schweinfurthii) Party Size: Observations, Camera Traps, and Bed Counts from a Savanna–Woodland Mosaic in the Issa Valley, Tanzania. INT J PRIMATOL 2020. [DOI: 10.1007/s10764-020-00142-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
AbstractStudying animal grouping behavior is important for understanding the causes and consequences of sociality and has implications for conservation. Chimpanzee (Pan troglodytes) party size is often assessed by counting individuals or extracted indirectly from camera trap footage or the number of nests. Little is known, however, about consistency across methods for estimating party size. We collected party size data for wild chimpanzees in the Issa valley, western Tanzania, using direct observations, camera traps, and nest counts over six years (2012–2018). We compared mean monthly party size estimates calculated using each method and found that estimates derived from direct observations were weakly positively correlated with those derived from camera traps. Estimates from nest counts were not significantly correlated with either direct observations or camera traps. Overall observed party size was significantly larger than that estimated from both camera traps and nest counts. In both the dry and wet seasons, observed party size was significantly larger than camera trap party size, but not significantly larger than nest party size. Finally, overall party size and wet season party size estimated from camera traps were significantly smaller than nest party size, but this was not the case in the dry season. Our results reveal how data collection methods influence party size estimates in unhabituated chimpanzees and have implications for comparative analysis within and across primate communities. Specifically, future work must consider how estimates were calculated before we can reliably investigate environmental influences on primate behavior.
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Samson DR, Louden LA, Gerstner K, Wylie S, Lake B, White BJ, Nunn CL, Hunt KD. Chimpanzee (Pan troglodytes schweinfurthii) Group Sleep and Pathogen-Vector Avoidance: Experimental Support for the Encounter-Dilution Effect. INT J PRIMATOL 2019. [DOI: 10.1007/s10764-019-00111-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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25
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Kamgang SA, Carme TC, Bobo KS, Abwe EE, Gonder MK, Sinsin B. Assessment of in situ nest decay rate for chimpanzees (Pan troglodytes ellioti Matschie, 1914) in Mbam-Djerem National Park, Cameroon: implications for long-term monitoring. Primates 2019; 61:189-200. [PMID: 31659555 PMCID: PMC7080673 DOI: 10.1007/s10329-019-00768-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 10/08/2019] [Indexed: 11/12/2022]
Abstract
Accurate assessment of great ape populations is a prerequisite for conservation planning. Indirect survey methods using nest and dung, and a set of conversion parameters related to nest decay rates, are increasingly used. Most surveys use the standing crop nest count (SCNC) method, whereby nests are counted along transects and the estimated nest density is converted into chimpanzee density using an often non-local nest decay rate. The use of non-local decay rate is thought to introduce substantial bias to ape population estimates given that nest decay rates vary with location, season, rainfall, nest shape, and tree species used. SCNC method has previously been applied in Mbam-Djerem National Park (MDNP) in Cameroon, for chimpanzee surveys using a non-local nest decay rate. This current study aimed to measure a local nest decay rate for MDNP and implications for chimpanzee population estimates in the MDNP. The mean nest decay rate estimated using a logistic regression analysis was 127 [95% CI (100–160)] days. Moreover, the results suggested that rainfall strongly influenced the nest decay rate over the early stage of the lifetime of the nests. The study confirms that estimates of chimpanzee density and abundance using non-local decay rates should be treated with caution. Our research emphasized the importance of using local nest decay rates and other survey methods which do not depend on decay rates to obtain more accurate estimates of chimpanzee densities in order to inform conservation strategies of these great apes in MDNP.
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Affiliation(s)
- Serge Alexis Kamgang
- Garoua Wildlife School, Face aéroport International de Garoua, PO Box 271, Garoua, Cameroon. .,Ministry of Forestry and Wildlife, Yaoundé, Cameroun. .,Laboratory of Applied Ecology, Faculty of Agricultural Science, University of Abomey-Calavi, 01, PO Box 526, Cotonou, Bénin.
| | - Tuneu Corral Carme
- Department of Animal Biology, Plant Biology and Ecology, Autonomous University of Barcelona, Bellaterra, 08193, Barcelona, Spain
| | - Kadiri Serge Bobo
- Department of Forestry, Faculty of Agronomy and Agricultural Sciences, University of Dschang, PO Box 222, Dschang, Cameroon
| | - Ekwoge Enang Abwe
- Department of Biology, Drexel University, Philadelphia, PA, 19104, USA
| | | | - Brice Sinsin
- Laboratory of Applied Ecology, Faculty of Agricultural Science, University of Abomey-Calavi, 01, PO Box 526, Cotonou, Bénin
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26
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Nesting, sleeping, and nighttime behaviors in wild and captive great apes. Primates 2019; 60:321-332. [PMID: 30972523 DOI: 10.1007/s10329-019-00723-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Accepted: 03/22/2019] [Indexed: 12/30/2022]
Abstract
The past few decades have seen a burgeoning of scientific studies on great apes' use of nests for sleeping in the wild, as well as their nesting behavior and sleep in captivity. We review recent advances in knowledge of these topics, with the aim of promoting information exchange between people working in the field and with captive great apes. We trace developments in research into nest-building techniques in adults and immatures, factors that influence selection of general sleeping sites and specific locations, social aspects of sleep, postures, and nighttime activities. We argue that exchanges of information deriving from studies of captive and wild apes are valuable for obtaining a better understanding of sleep-related adaptations in our nearest evolutionary neighbors, and conclude by making some recommendations regarding sleeping arrangements in captivity from a welfare perspective.
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27
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McLester E, Sweeney K, Stewart FA, Piel AK. Leopard (Panthera pardus) predation on a red-tailed monkey (Cercopithecus ascanius) in the Issa Valley, western Tanzania. Primates 2019; 60:15-19. [PMID: 30448971 PMCID: PMC6331503 DOI: 10.1007/s10329-018-0700-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 11/11/2018] [Indexed: 11/29/2022]
Abstract
Predation is predicted to be an important selection pressure for primates. Evidence for this hypothesis is rare, however, due to the scarcity of direct observations of primate predation. We describe an observation of leopard (Panthera pardus) predation on a red-tailed monkey (Cercopithecus ascanius schmidti) at the Issa Valley, a savanna-woodland mosaic landscape in western Tanzania. We compare rates of evidence of leopard presence between Issa and other primate study sites in sub-Saharan Africa. An increase in direct observations of leopards at Issa in recent years suggests that leopards may be habituating to researcher presence.
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Affiliation(s)
- Edward McLester
- School of Natural Sciences and Psychology, Liverpool John Moores University, Byrom Street, Liverpool, L33AF, UK.
| | - Kyle Sweeney
- Greater Mahale Ecosystem Research and Conservation Project, Box 60118, Dar es Salaam, Tanzania
| | - Fiona A Stewart
- School of Natural Sciences and Psychology, Liverpool John Moores University, Byrom Street, Liverpool, L33AF, UK
- Greater Mahale Ecosystem Research and Conservation Project, Box 60118, Dar es Salaam, Tanzania
| | - Alex K Piel
- School of Natural Sciences and Psychology, Liverpool John Moores University, Byrom Street, Liverpool, L33AF, UK
- Greater Mahale Ecosystem Research and Conservation Project, Box 60118, Dar es Salaam, Tanzania
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28
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Tagg N, McCarthy M, Dieguez P, Bocksberger G, Willie J, Mundry R, Stewart F, Arandjelovic M, Widness J, Landsmann A, Agbor A, Angedakin S, Ayimisin AE, Bessone M, Brazzola G, Corogenes K, Deschner T, Dilambaka E, Eno-Nku M, Eshuis H, Goedmakers A, Granjon AC, Head J, Hermans V, Jones S, Kadam P, Kambi M, Langergraber KE, Lapeyre V, Lapuente J, Lee K, Leinert V, Maretti G, Marrocoli S, Meier A, Nicholl S, Normand E, Ormsby LJ, Piel A, Robinson O, Sommer V, Ter Heegde M, Tickle A, Ton E, van Schijndel J, Vanleeuwe H, Vergnes V, Wessling E, Wittig RM, Zuberbuehler K, Kuehl H, Boesch C. Nocturnal activity in wild chimpanzees (Pan troglodytes): Evidence for flexible sleeping patterns and insights into human evolution. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 166:510-529. [PMID: 29989158 DOI: 10.1002/ajpa.23478] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 03/23/2018] [Accepted: 03/23/2018] [Indexed: 02/02/2023]
Abstract
OBJECTIVES We investigated occurrences and patterns of terrestrial nocturnal activity in wild chimpanzees (Pan troglodytes) and modelled the influence of various ecological predictors on nocturnal activity. METHODS Data were extracted from terrestrial camera-trap footage and ecological surveys from 22 chimpanzee study sites participating in the Pan African Programme: The Cultured Chimpanzee. We described videos demonstrating nocturnal activity, and we tested the effects of the percentage of forest, abundance of predators (lions, leopards and hyenas), abundance of large mammals (buffalos and elephants), average daily temperature, rainfall, human activity, and percent illumination on the probability of nocturnal activity. RESULTS We found terrestrial nocturnal activity to occur at 18 of the 22 study sites, at an overall average proportion of 1.80% of total chimpanzee activity, and to occur during all hours of the night, but more frequently during twilight hours. We found a higher probability of nocturnal activity with lower levels of human activity, higher average daily temperature, and at sites with a larger percentage of forest. We found no effect of the abundance of predators and large mammals, rainfall, or moon illumination. DISCUSSION Chimpanzee terrestrial nocturnal activity appears widespread yet infrequent, which suggests a consolidated sleeping pattern. Nocturnal activity may be driven by the stress of high daily temperatures and may be enabled at low levels of human activity. Human activity may exert a relatively greater influence on chimpanzee nocturnal behavior than predator presence. We suggest that chimpanzee nocturnal activity is flexible, enabling them to respond to changing environmental factors.
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Affiliation(s)
- Nikki Tagg
- Antwerp Zoo Centre for Research and Conservation, Royal Zoological Society of Antwerp, Belgium
| | - Maureen McCarthy
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Paula Dieguez
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | | | - Jacob Willie
- Antwerp Zoo Centre for Research and Conservation, Royal Zoological Society of Antwerp, Belgium
- Terrestrial Ecology Department, University of Gent, Belgium
| | - Roger Mundry
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Fiona Stewart
- School of Natural Sciences and Psychology, University of Liverpool, Liverpool, United Kingdom
| | - Mimi Arandjelovic
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Jane Widness
- Department of Anthropology, Yale University, New Haven, Connecticut
| | - Anja Landsmann
- University Medical Center, University of Leipzig, Leipzig, Germany
| | - Anthony Agbor
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Samuel Angedakin
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | | | - Mattia Bessone
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Gregory Brazzola
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | | | - Tobias Deschner
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | | | | | - Henk Eshuis
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | | | | | - Josephine Head
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Veerle Hermans
- Antwerp Zoo Centre for Research and Conservation, Royal Zoological Society of Antwerp, Belgium
| | - Sorrel Jones
- School of Biological Sciences, Royal Holloway University of London, Egham, United Kingdom
| | - Parag Kadam
- Faculty of Forestry, University of Toronto, Toronto, Canada
| | - Mohamed Kambi
- Pennsylvania State University (USA), Tanzania Program, c/o Udzungwa Mountains National Park, Kilombero, Tanzania
| | - Kevin E Langergraber
- School of Human Evolution and Social Change, Arizona State University, Tempe, Arizona
| | - Vincent Lapeyre
- Wild Chimpanzee Foundation (WCF), Abidjan, Côte d'Ivoire, Africa
| | - Juan Lapuente
- Comoé Chimpanzee Conservation Project, Comoé Research Station, Animal Ecology and Tropical Biology, Biozentrum, Universität Würzburg Tierökologie und Tropenbiologie (Zoologie III), Würzburg, Germany
| | - Kevin Lee
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Vera Leinert
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Giovanna Maretti
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Sergio Marrocoli
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Amelia Meier
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- Nicholas School of the Environment, Duke University, Durham
| | - Sonia Nicholl
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | | | - Lucy Jayne Ormsby
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Alex Piel
- School of Natural Sciences and Psychology Liverpool John Moores University, Liverpool, United Kingdom
| | - Orume Robinson
- Korup Rainforest Conservation Society, Mundemba, Cameroon, Africa
| | - Volker Sommer
- Department of Anthropology, University College London, London, United Kingdom
| | - Martijn Ter Heegde
- KfW Biodiversity Conservation and Sustainable Forest Management Program for GFA Consulting Group, Kinshasa, Democratic Republic of the Congo, Africa
| | - Alexander Tickle
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
| | - Els Ton
- Chimbo Foundation, Amsterdam, The Netherlands
| | | | | | - Virginie Vergnes
- Wild Chimpanzee Foundation (WCF), Abidjan, Côte d'Ivoire, Africa
| | - Erin Wessling
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- German Centre for Integrative Biodiversity Research (iDiv), Leipzig, Germany
| | - Roman M Wittig
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- Taï Chimpanzee Project, Centre Suisse des Recherche Scientifique, Abidjan, Côte d'Ivoire, Africa
| | | | - Hjalmar Kuehl
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
- German Centre for Integrative Biodiversity Research (iDiv), Leipzig, Germany
| | - Christophe Boesch
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
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Fruth B, Tagg N, Stewart F. Sleep and nesting behavior in primates: A review. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 166:499-509. [PMID: 29989164 DOI: 10.1002/ajpa.23373] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Revised: 11/30/2017] [Accepted: 12/02/2017] [Indexed: 12/30/2022]
Abstract
Sleep is a universal behavior in vertebrate and invertebrate animals, suggesting it originated in the very first life forms. Given the vital function of sleep, sleeping patterns and sleep architecture follow dynamic and adaptive processes reflecting trade-offs to different selective pressures. Here, we review responses in sleep and sleep-related behavior to environmental constraints across primate species, focusing on the role of great ape nest building in hominid evolution. We summarize and synthesize major hypotheses explaining the proximate and ultimate functions of great ape nest building across all species and subspecies; we draw on 46 original studies published between 2000 and 2017. In addition, we integrate the most recent data brought together by researchers from a complementary range of disciplines in the frame of the symposium "Burning the midnight oil" held at the 26th Congress of the International Primatological Society, Chicago, August 2016, as well as some additional contributors, each of which is included as a "stand-alone" article in this "Primate Sleep" symposium set. In doing so, we present crucial factors to be considered in describing scenarios of human sleep evolution: (a) the implications of nest construction for sleep quality and cognition; (b) the tree-to-ground transition in early hominids; (c) the peculiarities of human sleep. We propose bridging disciplines such as neurobiology, endocrinology, medicine, and evolutionary ecology, so that future research may disentangle the major functions of sleep in human and nonhuman primates, namely its role in energy allocation, health, and cognition.
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Affiliation(s)
- Barbara Fruth
- Centre for Research and Conservation/KMDA, Antwerp, Belgium.,Faculty of Science/School of Natural Sciences and Psychology, Liverpool John Moores University, United Kingdom.,Department of Developmental and Comparative Psychology, Max-Planck-Institute for Evolutionary Anthropology, Leipzig, Germany.,Faculty of Biology/Department of Neurobiology, Ludwig Maximilians University of Munich, Germany
| | - Nikki Tagg
- Centre for Research and Conservation/KMDA, Antwerp, Belgium
| | - Fiona Stewart
- Faculty of Science/School of Natural Sciences and Psychology, Liverpool John Moores University, United Kingdom
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30
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Stewart FA, Piel AK, Azkarate JC, Pruetz JD. Savanna chimpanzees adjust sleeping nest architecture in response to local weather conditions. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 166:549-562. [PMID: 29989162 DOI: 10.1002/ajpa.23461] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 01/10/2018] [Accepted: 03/03/2018] [Indexed: 11/05/2022]
Abstract
OBJECTIVES Great ape nests are hypothesized to aid safe, secure sleep via providing thermoregulation or protection from predators and vectors. We aimed to describe and investigate variation in chimpanzee nest architecture across two populations in response to local weather conditions. MATERIALS AND METHODS We experimentally tested whether nests provide insulation by measuring heat loss within and outside nests, and took detailed measurements of the number, size, and type of materials used in nest building across two dry-habitat research sites (Fongoli, Senegal, and Issa, Tanzania). We tested application of principal components analysis (PCA) to extract composite quantitative measures of the key components of shape and architecture, before testing how PCs vary across populations with overnight weather conditions that reflect hypothesized thermoregulatory function. RESULTS Heat loss is greater and occurs faster outside of nests. PCA allowed meaningful comparison of nests within and between sites. Nest variation at both sites revealed chimpanzees built thicker nests in cooler conditions and used more broken branches and support in moister conditions. Chimpanzees in Fongoli used more lining and mattress material in colder conditions, whilst in Issa nest depth and support branch size were larger in windier conditions. DISCUSSION Shape and architectural measures reflected insulation and stability of nest structure. Chimpanzees in Fongoli and Issa may achieve the same functional goals by adjusting nest shape and architecture in different ways. These results suggest that wild chimpanzees show flexible building techniques in response to local, overnight weather conditions in making an insulating and stable, supportive platform for sleep.
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Affiliation(s)
- Fiona A Stewart
- School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, L3 3AF, United Kingdom.,Department of Archaeology and Anthropology, University of Cambridge, Cambridge, CB2 3QG, United Kingdom
| | - Alexander K Piel
- School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, L3 3AF, United Kingdom
| | | | - Jill D Pruetz
- Department of Anthropology, Iowa State University, Ames, Iowa 50011
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31
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Samson DR, Bray J, Nunn CL. The cost of deep sleep: Environmental influences on sleep regulation are greater for diurnal lemurs. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2018; 166:578-589. [DOI: 10.1002/ajpa.23455] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 02/21/2018] [Accepted: 02/26/2018] [Indexed: 12/30/2022]
Affiliation(s)
- David R. Samson
- Department of Anthropology; University of Toronto; Mississauga
- Evolutionary Anthropology; Duke University; Tempe AZ
| | - Joel Bray
- School of Human Evolution and Social Change; Arizona State University
| | - Charles L. Nunn
- Evolutionary Anthropology; Duke University; Tempe AZ
- Duke Global Health Institute, Duke University
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32
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Thoemmes MS, Stewart FA, Hernandez-Aguilar RA, Bertone MA, Baltzegar DA, Borski RJ, Cohen N, Coyle KP, Piel AK, Dunn RR. Ecology of sleeping: the microbial and arthropod associates of chimpanzee beds. ROYAL SOCIETY OPEN SCIENCE 2018; 5:180382. [PMID: 29892462 PMCID: PMC5990838 DOI: 10.1098/rsos.180382] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 04/13/2018] [Indexed: 06/08/2023]
Abstract
The indoor environment created by the construction of homes and other buildings is often considered to be uniquely different from other environments. It is composed of organisms that are less diverse than those of the outdoors and strongly sourced by, or dependent upon, human bodies. Yet, no one has ever compared the composition of species found in contemporary human homes to that of other structures built by mammals, including those of non-human primates. Here we consider the microbes and arthropods found in chimpanzee beds, relative to the surrounding environment (n = 41 and 15 beds, respectively). Based on the study of human homes, we hypothesized that the microbes found in chimpanzee beds would be less diverse than those on nearby branches and leaves and that their beds would be primarily composed of body-associated organisms. However, we found that differences between wet and dry seasons and elevation above sea level explained nearly all of the observed variation in microbial diversity and community structure. While we can identify the presence of a chimpanzee based on the assemblage of bacteria, the dominant signal is that of environmental microbes. We found just four ectoparasitic arthropod specimens, none of which appears to be specialized on chimpanzees or their structures. These results suggest that the life to which chimpanzees are exposed while in their beds is predominately the same as that of the surrounding environment.
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Affiliation(s)
- Megan S. Thoemmes
- Department of Applied Ecology and Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, USA
| | - Fiona A. Stewart
- Ugalla Primate Project, Katavi Region, Tanzania
- School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK
- Department of Archaeology and Anthropology, University of Cambridge, Cambridge, UK
| | - R. Adriana Hernandez-Aguilar
- Ugalla Primate Project, Katavi Region, Tanzania
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Oslo, Norway
| | - Matthew A. Bertone
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC, USA
| | - David A. Baltzegar
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
- Genomic Sciences Laboratory, Office of Research, Innovation and Economic Development, North Carolina State University, Raleigh, NC, USA
| | - Russell J. Borski
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Naomi Cohen
- Ugalla Primate Project, Katavi Region, Tanzania
| | - Kaitlin P. Coyle
- Department of Biological Sciences, North Carolina State University, Raleigh, NC, USA
| | - Alexander K. Piel
- Ugalla Primate Project, Katavi Region, Tanzania
- School of Natural Sciences and Psychology, Liverpool John Moores University, Liverpool, UK
| | - Robert R. Dunn
- Department of Applied Ecology and Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC, USA
- The Center for Macroecology, Ecology and Conservation, Museum of Natural History, University of Copenhagen, Copenhagen, Denmark
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33
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Rakotomalala EJ, Rakotondraparany F, Perofsky AC, Lewis RJ. Characterization of the Tree Holes Used by Lepilemur ruficaudatus in the Dry, Deciduous Forest of Kirindy Mitea National Park. Folia Primatol (Basel) 2017; 88:28-41. [PMID: 28407630 DOI: 10.1159/000464406] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 02/21/2017] [Indexed: 11/19/2022]
Abstract
Knowledge of the key resources for a species is critical for developing an effective conservation strategy. Kirindy Mitea National Park is an important refuge for the red-tailed sportive lemur (Lepilemur ruficaudatus), a nocturnal folivorous lemur endemic to the dry deciduous forest of western Madagascar. Because L. ruficaudatus sleeps in tree holes during the day, sleeping trees may be an important resource for this species. Our goal was to characterize the sleeping sites used by L. ruficaudatus at the Ankoatsifaka Research Station in Kirindy Mitea National Park. In July and August 2012, tree characteristics were recorded for 60 L. ruficaudatus sleeping sites. Intact and alive trees, particularly Strychnos madagascariensis, were preferred by L. ruficaudatus. Sleeping holes were generally located in taller trees (median hole height = 4 m) and in trees with large girths (median = 20.5 cm). Greater protection from predators and thermal shifts may be provided by intact trees and concealed tree holes. Because tree characteristics can influence the presence and abundance of forest-living primates, the availability and characteristics of particular trees as potential sleeping shelters in a habitat must be taken into account in conservation strategies for L. ruficaudatus.
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Affiliation(s)
- Elvis J Rakotomalala
- Department of Animal Biology, University of Antananarivo, Antananarivo, Madagascar
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34
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Aronsen GP, Kirkham M. Inventory and Assessment of thePan troglodytes(Blumenbach, 1799) Skeletal Collection Housed at the Yale Peabody Museum. BULLETIN OF THE PEABODY MUSEUM OF NATURAL HISTORY 2017. [DOI: 10.3374/014.058.0107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Gary P. Aronsen
- Department of Anthropology, Biological Anthropology Laboratories, Yale University, P.O. Box 208277, New Haven CT 06520-8277 USA
| | - Megan Kirkham
- Division of Anthropology, Peabody Museum of Natural History, Yale University, New Haven CT USA
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35
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Feeding in fear? How adult male western chimpanzees (Pan troglodytes verus) adjust to predation and savanna habitat pressures. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2017; 163:480-496. [DOI: 10.1002/ajpa.23221] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 03/08/2017] [Accepted: 03/13/2017] [Indexed: 11/07/2022]
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36
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Do Predators and Thermoregulation Influence Choice of Sleeping Sites and Sleeping Behavior in Azara’s Owl Monkeys (Aotus azarae azarae) in Northern Argentina? INT J PRIMATOL 2017. [DOI: 10.1007/s10764-016-9946-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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37
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Factors Influencing the Survival of Sympatric Gorilla (Gorilla gorilla gorilla) and Chimpanzee (Pan troglodytes troglodytes) Nests. INT J PRIMATOL 2016. [DOI: 10.1007/s10764-016-9934-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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38
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Abstract
Over the past four decades, scientists have made substantial progress in understanding the evolution of sleep patterns across the Tree of Life. Remarkably, the specifics of sleep along the human lineage have been slow to emerge. This is surprising, given our unique mental and behavioral capacity and the importance of sleep for individual cognitive performance. One view is that our species' sleep architecture is in accord with patterns documented in other mammals. We promote an alternative view, that human sleep is highly derived relative to that of other primates. Based on new and existing evidence, we specifically propose that humans are more efficient in their sleep patterns than are other primates, and that human sleep is shorter, deeper, and exhibits a higher proportion of REM than expected. Thus, we propose the sleep intensity hypothesis: Early humans experienced selective pressure to fulfill sleep needs in the shortest time possible. Several factors likely served as selective pressures for more efficient sleep, including increased predation risk in terrestrial environments, threats from intergroup conflict, and benefits arising from increased social interaction. Less sleep would enable longer active periods in which to acquire and transmit new skills and knowledge, while deeper sleep may be critical for the consolidation of those skills, leading to enhanced cognitive abilities in early humans.
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Affiliation(s)
- David R Samson
- Department of Evolutionary Anthropology, Duke University, Durham, North Carolina, 27708, USA
| | - Charles L Nunn
- Duke Global Health Institute, Durham, North Carolina, 27710, USA
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39
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Kappelman J, Ketcham RA, Pearce S, Todd L, Akins W, Colbert MW, Feseha M, Maisano JA, Witzel A. Perimortem fractures in Lucy suggest mortality from fall out of tall tree. Nature 2016; 537:503-507. [PMID: 27571283 DOI: 10.1038/nature19332] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 07/25/2016] [Indexed: 11/09/2022]
Abstract
The Pliocene fossil 'Lucy' (Australopithecus afarensis) was discovered in the Afar region of Ethiopia in 1974 and is among the oldest and most complete fossil hominin skeletons discovered. Here we propose, on the basis of close study of her skeleton, that her cause of death was a vertical deceleration event or impact following a fall from considerable height that produced compressive and hinge (greenstick) fractures in multiple skeletal elements. Impacts that are so severe as to cause concomitant fractures usually also damage internal organs; together, these injuries are hypothesized to have caused her death. Lucy has been at the centre of a vigorous debate about the role, if any, of arboreal locomotion in early human evolution. It is therefore ironic that her death can be attributed to injuries resulting from a fall, probably out of a tall tree, thus offering unusual evidence for the presence of arborealism in this species.
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Affiliation(s)
- John Kappelman
- Department of Anthropology, The University of Texas at Austin, Austin, Texas 78712, USA.,Department of Geological Sciences, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Richard A Ketcham
- Department of Geological Sciences, The University of Texas at Austin, Austin, Texas 78712, USA
| | | | - Lawrence Todd
- Department of Anthropology, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Wiley Akins
- Department of Radio-Television-Film, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Matthew W Colbert
- Department of Geological Sciences, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Mulugeta Feseha
- Paleoanthropology and Paleoenvironment Program, Addis Ababa University, Addis Ababa, Ethiopia
| | - Jessica A Maisano
- Department of Geological Sciences, The University of Texas at Austin, Austin, Texas 78712, USA
| | - Adrienne Witzel
- Department of Anthropology, The University of Texas at Austin, Austin, Texas 78712, USA
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40
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Eppley TM, Donati G, Ganzhorn JU. Unusual sleeping site selection by southern bamboo lemurs. Primates 2016; 57:167-73. [DOI: 10.1007/s10329-016-0516-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 01/21/2016] [Indexed: 12/13/2022]
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41
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Harrison T. The Fossil Record and Evolutionary History of Hylobatids. DEVELOPMENTS IN PRIMATOLOGY: PROGRESS AND PROSPECTS 2016. [DOI: 10.1007/978-1-4939-5614-2_4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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42
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Johnson C, Piel AK, Forman D, Stewart FA, King AJ. The ecological determinants of baboon troop movements at local and continental scales. MOVEMENT ECOLOGY 2015; 3:14. [PMID: 26137307 PMCID: PMC4487562 DOI: 10.1186/s40462-015-0040-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 04/20/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND How an animal moves through its environment directly impacts its survival, reproduction, and thus biological fitness. A basic measure describing how an individual (or group) travels through its environment is Day Path Length (DPL), i.e., the distance travelled in a 24-hour period. Here, we investigate the ecological determinants of baboon (Papio spp.) troop DPL and movements at local and continental scales. RESULTS At the continental scale we explore the ecological determinants of annual mean DPL for 47 baboon troops across 23 different populations, updating a classic study by Dunbar (Behav Ecol Sociobiol 31: 35-49, 1992). We find that variation in baboon DPLs is predicted by ecological dissimilarity across the genus range. Troops that experience higher average monthly rainfall and anthropogenic influences have significantly shorter DPL, whilst troops that live in areas with higher average annual temperatures have significantly longer DPL. We then explore DPLs and movement characteristics (the speed and distribution of turning angles) for yellow baboons (Papio cynocephalus) at a local scale, in the Issa Valley of western Tanzania. We show that our continental-scale model is a good predictor of DPL in Issa baboons, and that troops move significantly slower, and over shorter distances, on warmer days. We do not find any effect of season or the abundance of fruit resources on the movement characteristics or DPL of Issa baboons, but find that baboons moved less during periods of high fruit availability. CONCLUSION Overall, this study emphasises the ability of baboons to adapt their ranging behaviour to a range of ecological conditions and highlights how investigations of movement patterns at different spatial scales can provide a more thorough understanding of the ecological determinants of movement.
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Affiliation(s)
- Caspian Johnson
- />Department of Biosciences, College of Science, Swansea University, Swansea, UK
| | - Alex K Piel
- />Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, Cambridge, UK
| | - Dan Forman
- />Department of Biosciences, College of Science, Swansea University, Swansea, UK
| | - Fiona A Stewart
- />Division of Biological Anthropology, Department of Archaeology and Anthropology, University of Cambridge, Cambridge, UK
| | - Andrew J King
- />Department of Biosciences, College of Science, Swansea University, Swansea, UK
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43
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Piel AK, Cohen N, Kamenya S, Ndimuligo SA, Pintea L, Stewart FA. Population status of chimpanzees in the Masito-Ugalla Ecosystem, Tanzania. Am J Primatol 2015; 77:1027-35. [PMID: 26119006 DOI: 10.1002/ajp.22438] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2014] [Accepted: 05/27/2015] [Indexed: 12/24/2022]
Abstract
More than 75 percent of Tanzania's chimpanzees live at low densities on land outside national parks. Chimpanzees are one of the key conservation targets in the region and long-term monitoring of these populations is essential for assessing the overall status of ecosystem health and the success of implemented conservation strategies. We aimed to assess change in chimpanzee density within the Masito-Ugalla Ecosystem (MUE) by comparing results of re-walking the same line transects in 2007 and 2014. We further used published remote sensing data derived from Landsat satellites to assess forest cover change within a 5 km buffer of these transects over that same period. We detected no statistically significant decline in chimpanzee density across the surveyed areas of MUE between 2007 and 2014, although the overall mean density of chimpanzees declined from 0.09 individuals/km(2) in 2007 to 0.05 individuals/km(2) in 2014. Whether this change is biologically meaningful cannot be determined due to small sample sizes and large, entirely overlapping error margins. It is therefore possible that the MUE chimpanzee population has been stable over this period and indeed in some areas (Issa Valley, Mkanga, Kamkulu) even showed an increase in chimpanzee density. Variation in chimpanzee habitat preference for ranging or nesting could explain variation in density at some of the survey sites between 2007 and 2014. We also found a relationship between increasing habitat loss and lower mean chimpanzee density. Future surveys will need to ensure a larger sample size, broader geographic effort, and random survey design, to more precisely determine trends in MUE chimpanzee density and population size over time.
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Affiliation(s)
- Alex K Piel
- Department of Archaeology and Anthropology, University of Cambridge, Cambridge CB2 3QG, United Kingdom.,Ugalla Primate Project, Kigoma, Tanzania
| | | | | | - Sood A Ndimuligo
- Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Blindern, Oslo, Norway
| | - Lilian Pintea
- The Jane Goodall Institute, 1595 Spring Hill Road, Suite 550 Vienna, Virginia
| | - Fiona A Stewart
- Department of Archaeology and Anthropology, University of Cambridge, Cambridge CB2 3QG, United Kingdom.,Ugalla Primate Project, Kigoma, Tanzania
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Abstract
Not all tropical fruits are equally desired by rainforest foragers and some fruit trees get depleted more quickly and carry fruit for shorter periods than others. We investigated whether a ripe-fruit specialist, the chimpanzee (Pan troglodytes verus), arrived earlier at breakfast sites with very ephemeral and highly sought-after fruit, like figs, than sites with less ephemeral fruit that can be more predictably obtained throughout the entire day. We recorded when and where five adult female chimpanzees spent the night and acquired food for a total of 275 full days during three fruit-scarce periods in a West African tropical rainforest. We found that chimpanzees left their sleeping nests earlier (often before sunrise when the forest is still dark) when breakfasting on very ephemeral fruits, especially when they were farther away. Moreover, the females positioned their sleeping nests more in the direction of the next day's breakfast sites with ephemeral fruit compared with breakfast sites with other fruit. By analyzing departure times and nest positioning as a function of fruit type and location, while controlling for more parsimonious explanations, such as temperature, we found evidence that wild chimpanzees flexibly plan their breakfast time, type, and location after weighing multiple disparate pieces of information. Our study reveals a cognitive mechanism by which large-brained primates can buffer the effects of seasonal declines in food availability and increased interspecific competition to facilitate first access to nutritious food. We discuss the implications for theories on hominoid brain-size evolution.
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45
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Granier N, Hambuckers A, Matsuzawa T, Huynen MC. Density estimates and nesting-site selection in chimpanzees of the Nimba Mountains, Côte d'Ivoire, and Guinea. Am J Primatol 2014; 76:999-1010. [PMID: 25099739 DOI: 10.1002/ajp.22278] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2013] [Revised: 02/12/2014] [Accepted: 02/24/2014] [Indexed: 11/09/2022]
Abstract
We investigated nesting behavior of non habituated chimpanzees populating the Nimba Mountains to document their abundance and their criterions of nesting-site selection. During a 19-month study we walked 80 km of transects and recces each month, and recorded 764 nests (mean group size = 2.23 nests) along with characteristics of vegetation structure and composition, topography, and seasonality. Population density estimated with two nest count methods ranged between 0.14 and 0.65 chimpanzee/km(2) . These values are lower than previous estimates, emphasizing the necessity of protecting remaining wild ape populations. Chimpanzees built nests in 108 tree species out of 437 identified, but 2.3% of total species comprised 52% of nests. Despite they preferred nesting in trees of 25-29 cm DBH and at a mean height of 8.02 m, we recorded an important proportion of terrestrial nests (8.2%) that may reflect a cultural trait of Nimba chimpanzees. A logistic model of nest presence formulated as a function of 12 habitat variables revealed preference for gallery and mountain forests rather than lowland forest, and old-growth forest rather than secondary forests. They nested more frequently in the study area during the dry season (December-April). The highest probability of observing nests was at 770 m altitude, particularly in steep locations (mean ground declivity = 15.54%). Several of the reported nest characteristics combined with the existence of two geographically separated clusters of nest, suggest that the study area constitutes the non-overlapping peripheral areas of two distinct communities. This nest-based study led us to findings on the behavioral ecology of Nimba chimpanzees, which constitute crucial knowledge to implement efficient and purpose-built conservation.
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Affiliation(s)
- Nicolas Granier
- Biology Ecology and Evolution, University of Liège, Liege, Belgium
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McGrew WC, Baldwin PJ, Marchant LF, Pruetz JD, Tutin CEG. Chimpanzees (Pan troglodytes verus) and their mammalian sympatriates: Mt. Assirik, Niokolo-Koba National Park, Senegal. Primates 2014; 55:525-32. [PMID: 24990446 DOI: 10.1007/s10329-014-0434-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 06/08/2014] [Indexed: 11/24/2022]
Abstract
In intact, mosaic ecosystems, chimpanzees are sympatric with a wide range of other mammals, which may be predators, prey, or competitors. We delve beyond the nominal data of species lists to interval-level data on 35 medium-bodied and large-bodied mammals encountered at a hot, dry, and open field site in far West Africa. Frequency of encounter, habitat where found, and number of individuals encountered are analysed for species for which enough data were accumulated. Further, we compare findings over three periods (1976-1979, 2000, 2012). Species most often encountered were those normally classed as typical savanna forms. Even a crude classification into forest, woodland, and grassland ecotypes yields differences in species likely to meet apes. Comparison of encounter rates over time was surprisingly congruent, although not all species seen in the 1970s survived to the 2000s. Overall, Assirik's mammalian fauna is comparable to palaeo-faunal guilds sympatric with various extinct hominins.
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Affiliation(s)
- William C McGrew
- Department of Archaeology and Anthropology, University of Cambridge, Fitzwilliam St., Cambridge, CB2 1QH, UK,
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Samson DR, Hunt KD. Chimpanzees preferentially select sleeping platform construction tree species with biomechanical properties that yield stable, firm, but compliant nests. PLoS One 2014; 9:e95361. [PMID: 24740283 PMCID: PMC3989313 DOI: 10.1371/journal.pone.0095361] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Accepted: 03/25/2014] [Indexed: 11/28/2022] Open
Abstract
The daily construction of a sleeping platform or “nest” is a universal behavior among large-bodied hominoids. Among chimpanzees, most populations consistently select particular tree species for nesting, yet the principles that guide species preferences are poorly understood. At Semliki, Cynometra alexandri constitutes only 9.6% of all trees in the gallery forest in which the study populations ranges, but it was selected for 73.6% of the 1,844 chimpanzee night beds we sampled. To determine whether physical properties influence nesting site selection, we measured the physical characteristics of seven common tree species at the Toro-Semliki Wildlife Reserve, Uganda. We determined stiffness and bending strength for a sample of 326 branches from the seven most commonly used tree species. We selected test-branches with diameters typically used for nest construction. We measured internode distance, calculated mean leaf surface area (cm2) and assigned a tree architecture category to each of the seven species. C. alexandri fell at the extreme of the sample for all four variables and shared a tree architecture with only one other of the most commonly selected species. C. alexandri was the stiffest and had the greatest bending strength; it had the smallest internode distance and the smallest leaf surface area. C. alexandri and the second most commonly selected species, Cola gigantea, share a ‘Model of Koriba’ tree architecture. We conclude that chimpanzees are aware of the structural properties of C. alexandri branches and choose it because its properties afford chimpanzees sleeping platforms that are firm, stable and resilient.
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Affiliation(s)
- David R. Samson
- Department of Anthropology, University of Nevada, Las Vegas, Las Vegas, Nevada, United States of America
- * E-mail:
| | - Kevin D. Hunt
- Department of Anthropology, Indiana University, Bloomington, Indiana, United States of America
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Genetic diversity at the edge: comparative assessment of Y-chromosome and autosomal diversity in eastern chimpanzees (Pan troglodytes schweinfurthii) of Ugalla, Tanzania. CONSERV GENET 2013. [DOI: 10.1007/s10592-013-0556-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Sleeping site selection by savanna chimpanzees in Ugalla, Tanzania. Primates 2013; 55:269-82. [PMID: 24293003 DOI: 10.1007/s10329-013-0400-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Accepted: 11/14/2013] [Indexed: 10/26/2022]
Abstract
We examined sleeping site selection by chimpanzees (Pan troglodytes) in the Ugalla savanna woodland area, western Tanzania, from 1994 to 2012. We established 488 km of line transects and recorded 379 chimpanzee beds within 30 m perpendicular to the transects. Comparisons between 60 × 60 m(2) quadrats containing new and recent beds and the remaining quadrats without beds along the transects indicated that evergreen forests accounted for disproportionately more area in quadrats with beds than in those without beds during both the dry and rainy seasons. In Ugalla, chimpanzees coexist with lions (Panthera leo) and leopards (Panthera pardus). They may sleep in forests to reduce predation risk by these carnivores, as trees are dense and the canopy is high and closed. The angle of slope was steeper in quadrats containing beds than in those without beds during the dry season, whereas the angle was less steep in quadrats with beds than in those without beds during the rainy season. Additionally, fewer beds were found further from forests. The distance between beds and forests during the dry season was shorter than that during the rainy season. Chimpanzees may sleep in or near forests and on slopes because of water pools in the valley forests along the slopes during the dry season. Quadrats with beds were at slightly higher altitude than those without beds during the rainy season; however, the difference was not significant during the dry season. The number of beds found in or close to feeding trees was not related to the fruiting period. Sleeping site selection by chimpanzees may be affected by predation pressure and water availability in the savanna woodland area.
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Tagg N, Willie J, Petre CA, Haggis O. Ground Night Nesting in Chimpanzees: New Insights from Central Chimpanzees(Pan troglodytes troglodytes)in South-East Cameroon. Folia Primatol (Basel) 2013; 84:362-83. [DOI: 10.1159/000353172] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2012] [Accepted: 05/21/2013] [Indexed: 11/19/2022]
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