Abrupt Decline in a Protected Population of Siamangs (Symphalangus syndactylus) in Southern Sumatra
Between 2011 and 2016, approximately 50% of siamangs in the Way Canguk Research Area disappeared, including members of 7 of 12 habituated groups. Demographic data from 1998 to 2015 confirm that the population decline in the habituated groups reflects a larger trend in the local population. There was no evidence of hunting of primates in the area, and ecological data do not suggest substantial changes in food availability or predation pressure during this period. From 2011 to 2014, we monitored the habituated groups only intermittently, and most deaths or disappearances were not observed. However, in 2014-2016, we monitored...
Source: Folia Primatologica - August 23, 2017 Category: Physiology Source Type: research
Techniques Used by Bearded Capuchin Monkeys (Sapajus libidinosus) to Access Water in a Semi-Arid Environment of North-Eastern Brazil
The exploratory behaviour and the ability of capuchin monkeys to use tools allows them to thrive at times and places of limited food and water abundance, such as in semi-arid environments. Here, we report the behaviours employed by individuals belonging to a wild group of bearded capuchin monkeys (Sapajus libidinosus) to access natural water sources in a dry forest of north-eastern Brazil. An adult female employed a twig as a tool and her tail to gain access to accumulated rainwater in a tree hole, and other individuals used their hands and mouth to manipulate orchids' pseudobulbs and the liquid endosperm of palm nuts. The...
Source: Folia Primatologica - August 23, 2017 Category: Physiology Source Type: research
Group Composition and Monandry in Grizzled Langurs, Presbytis comata, on Java
Grizzled langurs,Presbytis comata, a largely sexually monomorphic species, are reported to occur in populations where either the majority of groups comprise 1 adult male with 1 adult female, or where groups comprise 1 adult male with multiple females. As such, they may have a monandrous mating system. I investigated whether 1-male/1-female groups indeed form a significant part of the species' social system, and whether habitat variation (forest fragment size, distance to the forest edge, altitude) affects social organization. I found the species from sea level to 2,565 m above sea level in groups from 1 to 13 individuals. ...
Source: Folia Primatologica - August 23, 2017 Category: Physiology Source Type: research
Abrupt Decline in a Protected Population of Siamangs ( < b > < i > Symphalangus syndactylus < /i > < /b > ) in Southern Sumatra
Between 2011 and 2016, approximately 50% of siamangs in the Way Canguk Research Area disappeared, including members of 7 of 12 habituated groups. Demographic data from 1998 to 2015 confirm that the population decline in the habituated groups reflects a larger trend in the local population. There was no evidence of hunting of primates in the area, and ecological data do not suggest substantial changes in food availability or predation pressure during this period. From 2011 to 2014, we monitored the habituated groups only intermittently, and most deaths or disappearances were not observed. However, in 2014-2016, we monitored...
Source: Folia Primatologica - August 22, 2017 Category: Physiology Source Type: research
Techniques Used by Bearded Capuchin Monkeys ( < b > < i > Sapajus libidinosus < /i > < /b > ) to Access Water in a Semi-Arid Environment of North-Eastern Brazil
The exploratory behaviour and the ability of capuchin monkeys to use tools allows them to thrive at times and places of limited food and water abundance, such as in semi-arid environments. Here, we report the behaviours employed by individuals belonging to a wild group of bearded capuchin monkeys (Sapajus libidinosus) to access natural water sources in a dry forest of north-eastern Brazil. An adult female employed a twig as a tool and her tail to gain access to accumulated rainwater in a tree hole, and other individuals used their hands and mouth to manipulate orchids' pseudobulbs and the liquid endosperm of palm nuts. The...
Source: Folia Primatologica - August 22, 2017 Category: Physiology Source Type: research
Group Composition and Monandry in Grizzled Langurs, < b > < i > Presbytis comata, < /i > < /b > on Java
Grizzled langurs,Presbytis comata, a largely sexually monomorphic species, are reported to occur in populations where either the majority of groups comprise 1 adult male with 1 adult female, or where groups comprise 1 adult male with multiple females. As such, they may have a monandrous mating system. I investigated whether 1-male/1-female groups indeed form a significant part of the species' social system, and whether habitat variation (forest fragment size, distance to the forest edge, altitude) affects social organization. I found the species from sea level to 2,565 m above sea level in groups from 1 to 13 individuals. ...
Source: Folia Primatologica - August 22, 2017 Category: Physiology Source Type: research
Tooth Wear Inclination in Great Ape Molars
In this study, we analyze and compare the wear patterns ofPongo pygmaeus,Gorilla gorillagorilla andPan troglodytes schweinfurthiilower molars, focusing on the degree of inclination of specific wear facets. The variation in wear angles appears to be indicative of jaw movements and the specific stresses imposed on food during mastication, reflecting thus the ecology of these species. Orangutans exhibit flatter wear angles, more typical of a diet consisting of hard and brittle foods, while gorillas show a wear pattern with a high degree of inclination, reflecting thus their more leafy diet. Chimpanzees, on the other hand, sho...
Source: Folia Primatologica - August 15, 2017 Category: Physiology Source Type: research
Laterality of Grooming and Tool Use in a Group of Captive Bonobos (Pan paniscus)
Humans exhibit population level handedness for the right hand; however, the evolution of this behavioral phenotype is poorly understood. Here, we compared the laterality of a simple task (grooming) and a complex task (tool use) to investigate whether increasing task difficulty elicited individual hand preference among a group of captive bonobos (Pan paniscus). Subjects were 17 bonobos housed at the Columbus Zoo and Aquarium. Laterality of grooming was recorded using group scans; tool use was recorded using all-occurrence sampling. Grooming was characterized as unimanual or bimanual, and both tasks were scored as right-hand...
Source: Folia Primatologica - August 14, 2017 Category: Physiology Source Type: research
Laterality of Grooming and Tool Use in a Group of Captive Bonobos ( < b > < i > Pan paniscus < /i > < /b > )
Humans exhibit population level handedness for the right hand; however, the evolution of this behavioral phenotype is poorly understood. Here, we compared the laterality of a simple task (grooming) and a complex task (tool use) to investigate whether increasing task difficulty elicited individual hand preference among a group of captive bonobos (Pan paniscus). Subjects were 17 bonobos housed at the Columbus Zoo and Aquarium. Laterality of grooming was recorded using group scans; tool use was recorded using all-occurrence sampling. Grooming was characterized as unimanual or bimanual, and both tasks were scored as right-hand...
Source: Folia Primatologica - August 11, 2017 Category: Physiology Source Type: research
XXIII Italian Association of Primatology Congress. Trento, Italy, September 14-16, 2017: Abstracts
Folia Primatol 2017;88:189-209 (Source: Folia Primatologica)
Source: Folia Primatologica - August 9, 2017 Category: Physiology Source Type: research
7th European Federation for Primatology Meeting. 30e Colloque de la Soci été Francophone de Primatologie Strasbourg, France, August 21-25, 2017: Abstracts
Folia Primatol 2017;88:77-188 (Source: Folia Primatologica)
Source: Folia Primatologica - August 2, 2017 Category: Physiology Source Type: research
7th European Federation for Primatology Meeting. 30 < sup > e < /sup > Colloque de la Soci été Francophone de Primatologie Strasbourg, France, August 21-25, 2017: Abstracts
Folia Primatol 2017;88:77-188 (Source: Folia Primatologica)
Source: Folia Primatologica - July 28, 2017 Category: Physiology Source Type: research
Fran çoise-Kyou Jouffroy (1931-2016)
Folia Primatol 2017;88:75-76 (Source: Folia Primatologica)
Source: Folia Primatologica - July 18, 2017 Category: Physiology Source Type: research
Diet and Activity of Macaca assamensis in Wild and Semi-Provisioned Groups in Shivapuri Nagarjun National Park, Nepal
Studying the behavioural flexibility and adaptability of macaques to different habitats is one approach to designing a conservation plan. To determine the activity budget and feeding behaviour and evaluate the effects of seasonality in wild and human- altered habitats of Assamese macaques (Macaca assamensis), we conducted this study in the Nagarjun forest of Shivapuri-Nagarjun National Park (SNNP) in central Nepal. We also updated the list of plant food items of Assamese macaques in the SNNP. Using scan and all-occurrence sampling, we recorded the diets and activities of Assamese macaques in 2 social groups, a wild-feeding...
Source: Folia Primatologica - July 12, 2017 Category: Physiology Source Type: research
Diet and Activity of < b > < i > Macaca assamensis < /i > < /b > in Wild and Semi-Provisioned Groups in Shivapuri Nagarjun National Park, Nepal
Studying the behavioural flexibility and adaptability of macaques to different habitats is one approach to designing a conservation plan. To determine the activity budget and feeding behaviour and evaluate the effects of seasonality in wild and human- altered habitats of Assamese macaques (Macaca assamensis), we conducted this study in the Nagarjun forest of Shivapuri-Nagarjun National Park (SNNP) in central Nepal. We also updated the list of plant food items of Assamese macaques in the SNNP. Using scan and all-occurrence sampling, we recorded the diets and activities of Assamese macaques in 2 social groups, a wild-feeding...
Source: Folia Primatologica - July 11, 2017 Category: Physiology Source Type: research
