Maria A Van Noordwijk
Biographic Data
| ID | 625201 |
|---|---|
| NAME | Maria A Van Noordwijk |
| GIVEN NAMES | Maria A |
| FAMILY NAME | Van Noordwijk |
| SIGNATURE | VAN NOORDWIJK M A |
| AFFILIATIONS | University of Zurich |
| ORCID | 0000-0001-9633-0845 |
| VERIFIED | Yes |
| TOTAL WORKS | 34 |
| TOTAL CITATIONS | 43 |
| AUTHOR COUNT | 34 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 1983 |
| LATEST PUBLICATION YEAR | 2024 |
| H-INDEX | 3 |
Maternal Behavior in Sumatran Orangutans (Pongo abelii) is Modulated by Mother-Offspring Characteristics and Socioecological Factors
Mammalian mothers flexibly invest in their offspring to maximize their lifetime fitness. Flexible maternal investment may be particularly important in large-brained species with prolonged maternal care, e.g., in great apes. We investigated the effects of socioecological factors and mother–offspring characteristics on nine maternal behaviors in wild Sumatran orangutans ( Pongo abelii ; N = 22 mother-offspring pairs; >11,200 hr of focal data from 2…
Alternative reproductive tactics of unflanged and flanged male orangutans revisited
In many slowly developing mammal species, males reach sexual maturity well before they develop secondary sexual characteristics. Sexually mature male orangutans have exceptionally long periods of developmental arrest. The two male morphs have been associated with behavioral alternative reproductive tactics, but this interpretation is based on cross‐sectional analyses predominantly of Northwest Sumatran populations. Here we present the first longi…
Slow loris (Nycticebus borneanus) consumption by a wild Bornean orangutan (Pongo pygmaeus wurmbii)
After the smoke has cleared: Extended low fruit productivity following forest fires decreased gregariousness and social tolerance among wild female Bornean orangutans (Pongo pygmaeus wurmbii)
As climate change continues to fundamentally alter resource landscapes, the ability to flexibly respond to spatio-temporal changes in the distribution of preferred food sources is increasingly important for the overall health and fitness of animals living in seasonal, variable, and/or changing environments. Here, we investigate the effects of an uncharacteristically long period of fruit scarcity, following widespread thick haze caused by peat and…
Range‐wide indicators of African great ape density distribution
Species distributions are influenced by processes occurring at multiple spatial scales. It is therefore insufficient to model species distribution at a single geographic scale, as this does not provide the necessary understanding of determining factors. Instead, multiple approaches are needed, each differing in spatial extent, grain, and research objective. Here, we present the first attempt to model continent‐wide great ape density distribution.…
Towards systematic and evidence‐based conservation planning for western chimpanzees
As animal populations continue to decline, frequently driven by large‐scale land‐use change, there is a critical need for improved environmental planning. While data‐driven spatial planning is widely applied in conservation, as of yet it is rarely used for primates. The western chimpanzee ( Pan troglodytes verus ) declined by 80% within 24 years and was uplisted to Critically Endangered by the IUCN Red List of Threatened Species in 2016. To suppo…
Social and ecological correlates of space use patterns in Bwindi mountain gorillas
Space use patterns determine access to resources necessary for survival and reproduction. Although it is recognized that the interplay between social and ecological variables shapes spacing patterns, few studies in group-living animals have simultaneously assessed their importance in a comprehensive approach using different spatiotemporal space use measures. In territorial species, such patterns are strongly determined by between-group competitio…
The slow ape: High infant survival and long interbirth intervals in wild orangutans
Social and demographic correlates of male androgen levels in wild white‐faced capuchin monkeys ( Cebus capucinus )
The Challenge Hypothesis, designed originally to explain the patterning of competitive behavior and androgen levels in seasonally breeding birds, predicts that males will increase their androgen levels in order to become more competitive in reproductive contexts. Here we test predictions derived from the Challenge Hypothesis in white-faced capuchin monkeys (Cebus capucinus), a species that has somewhat seasonal reproduction. We analyzed demograph…
Nutritional ecology of wild Bornean orangutans ( Pongo pygmaeus wurmbii ) in a peat swamp habitat: Effects of age, sex, and season
The spatial and temporal variation in food abundance has strong effects on wildlife feeding and nutrition. This variation is exemplified by the peatland forests of Central Kalimantan, which are characterized by unpredictable fruiting fluctuations, relatively low levels of fruit availability, and low fruit periods (<3% of trees fruiting) that can last nearly a year. Challenged by these environments, large, arboreal frugivores like orangutans must …
Who is who matters—The effects of pseudoreplication in stable isotope analyses
Stable isotope analysis in free-ranging primates is a promising new avenue in reconstructing feeding niches and temporal dietary variation. Particularly, the large sample sizes obtained from non-invasively collected hair and fecal samples from nests of great apes offer great potential. However, analyzing repeated observations of the same individuals without controlling for potential differences among them means to "pseudoreplicate" and can lead t…
Validation of an acoustic location system to monitor Bornean orangutan ( Pongo pygmaeus wurmbii ) long calls
The long call is an important vocal communication signal in the widely dispersed, semi-solitary orangutan. Long calls affect individuals' ranging behavior and mediate social relationships and regulate encounters between dispersed individuals in a dense rainforest. The aim of this study was to test the utility of an Acoustic Location System (ALS) for recording and triangulating the loud calls of free-living primates. We developed and validated a d…
Why do orangutans leave the trees? Terrestrial behavior among wild Bornean orangutans ( Pongo pygmaeus wurmbii ) at Tuanan, Central Kalimantan
Orangutans (genus Pongo) are the largest arboreal mammals, but Bornean orangutans (P. pygmaeus spp.) also spend time on the ground. Here, we investigate ground use among orangutans using 32,000 hr of direct focal animal observations from a well-habituated wild population of Bornean orangutans (P. p. wurmbii) living in a closed-canopy swamp forest at Tuanan, Central Kalimantan, Indonesia. Ground use did not change with increasing observation time …
Audience effects, but not environmental influences, explain variation in gorilla close distance vocalizations—A test of the acoustic adaptation hypothesis
Close distance vocalizations are an integral part of primate vocal communication. They exhibit large acoustic variation which has been suggested to constitute flexible responses to the highly variable social setting of group living animals. However, a recent study suggested that acoustic variation in close distance calls of baboons may also arise from acoustic adaptations to environmental factors in order to counteract sound degradation. We teste…
Endocrinological correlates of male bimaturism in wild Bornean orangutans
Among primates, orangutans are unique in having pronounced male bimaturism leading to two fully adult morphs that differ in both physical appearance and behavior. While unflanged males have a female-like appearance, flanged males have the full suite of secondary sexual characteristics, including cheek flanges and a large throat sac. So far, hormonal correlates of arrested development in unflanged males and the expression of secondary sexual chara…
Modeling Primate Abundance in Complex Landscapes: A Case Study From the Udzungwa Mountains of Tanzania
Informing conservation management about structural versus functional connectivity: A case‐study of Cross River gorillas
Connectivity among subpopulations is vital for the persistence of small and fragmented populations. For management interventions to be effective conservation planners have to make the critical distinction between structural connectivity (based on landscape structure) and functional connectivity (which considers both landscape structure and organism-specific behavioral attributes) which can differ considerably within a given context. We assessed s…
New evidence for self‐medication in bonobos: Manniophyton fulvum leaf‐ and stemstrip‐swallowing from LuiKotale, Salonga National Park, DR Congo
The swallowing of entire leaves by apes across Africa without chewing has been observed for over 40 plant species. Here we add evidence for (a) a new site, LuiKotale where leaf-swallowing of Manniophyton fulvum (Euphorbiaceae) is observed in bonobos, (b) a so far unreported ingestion of unchewed stemstrips of M. fulvum, we name stemstrip-swallowing; and (c) a test of some of the requirements put forward by Huffman for the assessment of plants ing…
Long‐Term Temporal and Spatial Dynamics of Food Availability for Endangered Mountain Gorillas in Volcanoes National Park, Rwanda
Monitoring temporal and spatial changes in the resource availability of endangered species contributes to their conservation. The number of critically endangered mountain gorillas ( Gorilla beringei beringei ) in the Virunga Volcano population has doubled over the past three decades, but no studies have examined how food availability has changed during that period. First, we assessed if the plant species consumed by the gorillas have changed in a…
The evolution of the patterning of human lactation: A comparative perspective
Some four decades ago, Jeanne Altmann started her detailed field studies of baboon mothers and their infants with a focus on the behavioral ecology of maternal reproductive investment. Around the same time, Sarah Hrdy studied langur mothers and their infants, focusing on the influence of the social environment on a female's reproductive options and decisions. Their pioneering work has inspired many subsequent studies of female primate reproductio…
A model for the evolution of developmental arrest in male orangutans
Male Sumatran orangutans ( Pongo abelii ) may delay for many years the acquisition of the full array of secondary sexual traits, including their characteristic cheek flanges. Such flexible developmental arrest is unique among male primates. Among male Bornean orangutans ( Pongo pygmaeus ) such long delays appear less common. Here, we develop a simple model to identify the conditions under which developmental arrest can be adaptive. We show that t…
Social learning of diet and foraging skills by wild immature Bornean orangutans: Implications for culture
Studies of social learning in the wild are important to complement findings from experiments in captivity. In this field study, immature Bornean orangutans rarely foraged independently but consistently followed their mothers' choices. Their diets were essentially identical to their mothers' even though not all mothers had the same diet. This suggests vertical transmission of diet by enhancement. Also, immatures selectively observed their mothers …
Methods for calculating activity budgets compared: A case study using orangutans
The results of comparisons of behavioral data between individuals, age–sex classes, seasons, sites and possibly even species may depend on sample size and the computational method used. To establish whether these are valid concerns, we compared results for percentage time spent feeding on major food types (fruit, leaves, flowers, invertebrates, bark, pith and other) for two orangutan populations in Sabangau (24 months) and Tuanan (29 months), Ind…
The relationship between socio‐sexual behavior and salivary cortisol in bonobos: Tests of the tension regulation hypothesis
Bonobos are known for their pacifistic behavior and their large repertoire of behaviors that are thought to serve conflict resolution. One is an unusual form of ventro‐ventral mounting that facilitates genital contacts (GC). Various hypotheses have been proposed to explain its function. In this study we tested predictions of the tension regulation hypothesis using salivary cortisol as a marker for social stress. The results indicate a temporal re…
Development of independence
Among known mammals, orangutans have the longest period of dependence and exclusive association between mother and offspring before a younger sibling is born. Comparison of available data on wild Sumatran and Bornean orangutans reveals a similar development of essential survival skills up to c. 5 years of age, but among Bornean orangutans earlier complete weaning and start of independent ranging through cessation of the association between mother…
Development of ecological competence in Sumatran orangutans
Data on orangutans (Pongo pygmaeus abelii) living in a Sumatran swamp forest yield an estimated median interbirth interval of at least 8 years, concurring with findings from other sites. This longest known mammalian interbirth interval appears due to maternal amenorrhea during the long exclusive dependence of the offspring. We describe the development of various components of offspring independence. In this arboreal ape, 3-year-olds had largely r…
The slow ape: High infant survival and long interbirth intervals in wild orangutans
Modeling Primate Abundance in Complex Landscapes: A Case Study From the Udzungwa Mountains of Tanzania
Maternal Behavior in Sumatran Orangutans (Pongo abelii) is Modulated by Mother-Offspring Characteristics and Socioecological Factors
Mammalian mothers flexibly invest in their offspring to maximize their lifetime fitness. Flexible maternal investment may be particularly important in large-brained species with prolonged maternal care, e.g., in great apes. We investigated the effects of socioecological factors and mother–offspring characteristics on nine maternal behaviors in wild Sumatran orangutans ( Pongo abelii ; N = 22 mother-offspring pairs; >11,200 hr of focal data from 2…
After the smoke has cleared: Extended low fruit productivity following forest fires decreased gregariousness and social tolerance among wild female Bornean orangutans (Pongo pygmaeus wurmbii)
As climate change continues to fundamentally alter resource landscapes, the ability to flexibly respond to spatio-temporal changes in the distribution of preferred food sources is increasingly important for the overall health and fitness of animals living in seasonal, variable, and/or changing environments. Here, we investigate the effects of an uncharacteristically long period of fruit scarcity, following widespread thick haze caused by peat and…
A model for the evolution of developmental arrest in male orangutans
Male Sumatran orangutans ( Pongo abelii ) may delay for many years the acquisition of the full array of secondary sexual traits, including their characteristic cheek flanges. Such flexible developmental arrest is unique among male primates. Among male Bornean orangutans ( Pongo pygmaeus ) such long delays appear less common. Here, we develop a simple model to identify the conditions under which developmental arrest can be adaptive. We show that t…
Party size and early detection of predators in sumatran forest primates
Interannual variability in fruit abundance and the reproductive seasonality in Sumatran Long‐tailed macaques (Macaca fascicularis)
In an environment with a seasonal food supply, most primate species show birth peaks which precede the peak food period by some two to five months. Sumatran Long‐tailed macaques (Macaca fascicularis), however, showed birth peaks during or after the fruit peak. Years of high birth rates and early birth peaks alternated with years of low birth rates and late peaks. The timing of births was strongly influenced by a female's condition, which depends …
Population status of the Simeulue monkey ( Macaca fascicularis fusca )
The oceanic island of Simeulue, west of Sumatra, is inhabited by a distinct subspecies of the long‐tailed macaque ( Macaca fascicularis fusca ) [Miller, 1903]. In January 1982 and March 1984, a survey was conducted to establish its population status. The monkey is morphologically different from other Sunda shelf M. fascicularis populations. In productive habitats, it lives in small groups (10–15 individuals) and reaches a density of more than one…
A pilot study of the social correlates of levels of urinary cortisol, prolactin, and testosterone in wild long-tailed macaques (Macaca fascicularis)
Sex and social evolution in primates
Introduction Life history and male infanticide risk Infanticide by males unlikely or unable to have fathered a female's current dependent offspring is an adaptive male reproductive strategy if the mother can soon be fertilised again and the infanticidal male is in a position to be the likely sire of her next infant (Hrdy, 1979; Hrdy, Janson and van Schaik, 1995). It is remarkably common among primates (Hausfater and Hrdy, 1984; Struhsaker and Lel…
The effects of dominance rank and group size on female lifetime reproductive success in wild long-tailed macaques,Macaca fascicularis
Infanticide by Males and its Implications
Male primates, carnivores and rodents sometimes kill infants that they did not sire. Infanticide by males is a relatively common phenomenon in these groups, but tends to be rare in any given species. Is this behavior pathological or accidental, or does it reflect a conditional reproductive strategy for males in certain circumstances? In this book, case studies and reviews confirm the adaptive nature of infanticide in males in primates, and help t…
Development of ecological competence in Sumatran orangutans
Data on orangutans (Pongo pygmaeus abelii) living in a Sumatran swamp forest yield an estimated median interbirth interval of at least 8 years, concurring with findings from other sites. This longest known mammalian interbirth interval appears due to maternal amenorrhea during the long exclusive dependence of the offspring. We describe the development of various components of offspring independence. In this arboreal ape, 3-year-olds had largely r…
Development of independence
Among known mammals, orangutans have the longest period of dependence and exclusive association between mother and offspring before a younger sibling is born. Comparison of available data on wild Sumatran and Bornean orangutans reveals a similar development of essential survival skills up to c. 5 years of age, but among Bornean orangutans earlier complete weaning and start of independent ranging through cessation of the association between mother…
Begging for information: Mother–offspring food sharing among wild Bornean orangutans
Transfer of solid food from mothers or other adults to dependent offspring is commonly observed in various primate species and both nutritional and informational benefits have been proposed to explain the function of such food sharing. Predictions from these hypotheses are tested using observational data on wild orangutans ( Pongo pygmaeus wurmbii ) at Tuanan, Central Borneo, Indonesia. In 1,145 hr of focal observation and 458 recorded food inter…
Methods for calculating activity budgets compared: A case study using orangutans
The results of comparisons of behavioral data between individuals, age–sex classes, seasons, sites and possibly even species may depend on sample size and the computational method used. To establish whether these are valid concerns, we compared results for percentage time spent feeding on major food types (fruit, leaves, flowers, invertebrates, bark, pith and other) for two orangutan populations in Sabangau (24 months) and Tuanan (29 months), Ind…
The relationship between socio‐sexual behavior and salivary cortisol in bonobos: Tests of the tension regulation hypothesis
Bonobos are known for their pacifistic behavior and their large repertoire of behaviors that are thought to serve conflict resolution. One is an unusual form of ventro‐ventral mounting that facilitates genital contacts (GC). Various hypotheses have been proposed to explain its function. In this study we tested predictions of the tension regulation hypothesis using salivary cortisol as a marker for social stress. The results indicate a temporal re…
Social learning of diet and foraging skills by wild immature Bornean orangutans: Implications for culture
Studies of social learning in the wild are important to complement findings from experiments in captivity. In this field study, immature Bornean orangutans rarely foraged independently but consistently followed their mothers' choices. Their diets were essentially identical to their mothers' even though not all mothers had the same diet. This suggests vertical transmission of diet by enhancement. Also, immatures selectively observed their mothers …
A model for the evolution of developmental arrest in male orangutans
Male Sumatran orangutans ( Pongo abelii ) may delay for many years the acquisition of the full array of secondary sexual traits, including their characteristic cheek flanges. Such flexible developmental arrest is unique among male primates. Among male Bornean orangutans ( Pongo pygmaeus ) such long delays appear less common. Here, we develop a simple model to identify the conditions under which developmental arrest can be adaptive. We show that t…
Long‐Term Temporal and Spatial Dynamics of Food Availability for Endangered Mountain Gorillas in Volcanoes National Park, Rwanda
Monitoring temporal and spatial changes in the resource availability of endangered species contributes to their conservation. The number of critically endangered mountain gorillas ( Gorilla beringei beringei ) in the Virunga Volcano population has doubled over the past three decades, but no studies have examined how food availability has changed during that period. First, we assessed if the plant species consumed by the gorillas have changed in a…
The evolution of the patterning of human lactation: A comparative perspective
Some four decades ago, Jeanne Altmann started her detailed field studies of baboon mothers and their infants with a focus on the behavioral ecology of maternal reproductive investment. Around the same time, Sarah Hrdy studied langur mothers and their infants, focusing on the influence of the social environment on a female's reproductive options and decisions. Their pioneering work has inspired many subsequent studies of female primate reproductio…
Informing conservation management about structural versus functional connectivity: A case‐study of Cross River gorillas
Connectivity among subpopulations is vital for the persistence of small and fragmented populations. For management interventions to be effective conservation planners have to make the critical distinction between structural connectivity (based on landscape structure) and functional connectivity (which considers both landscape structure and organism-specific behavioral attributes) which can differ considerably within a given context. We assessed s…
New evidence for self‐medication in bonobos: Manniophyton fulvum leaf‐ and stemstrip‐swallowing from LuiKotale, Salonga National Park, DR Congo
The swallowing of entire leaves by apes across Africa without chewing has been observed for over 40 plant species. Here we add evidence for (a) a new site, LuiKotale where leaf-swallowing of Manniophyton fulvum (Euphorbiaceae) is observed in bonobos, (b) a so far unreported ingestion of unchewed stemstrips of M. fulvum, we name stemstrip-swallowing; and (c) a test of some of the requirements put forward by Huffman for the assessment of plants ing…
Validation of an acoustic location system to monitor Bornean orangutan ( Pongo pygmaeus wurmbii ) long calls
The long call is an important vocal communication signal in the widely dispersed, semi-solitary orangutan. Long calls affect individuals' ranging behavior and mediate social relationships and regulate encounters between dispersed individuals in a dense rainforest. The aim of this study was to test the utility of an Acoustic Location System (ALS) for recording and triangulating the loud calls of free-living primates. We developed and validated a d…
Why do orangutans leave the trees? Terrestrial behavior among wild Bornean orangutans ( Pongo pygmaeus wurmbii ) at Tuanan, Central Kalimantan
Orangutans (genus Pongo) are the largest arboreal mammals, but Bornean orangutans (P. pygmaeus spp.) also spend time on the ground. Here, we investigate ground use among orangutans using 32,000 hr of direct focal animal observations from a well-habituated wild population of Bornean orangutans (P. p. wurmbii) living in a closed-canopy swamp forest at Tuanan, Central Kalimantan, Indonesia. Ground use did not change with increasing observation time …
Audience effects, but not environmental influences, explain variation in gorilla close distance vocalizations—A test of the acoustic adaptation hypothesis
Close distance vocalizations are an integral part of primate vocal communication. They exhibit large acoustic variation which has been suggested to constitute flexible responses to the highly variable social setting of group living animals. However, a recent study suggested that acoustic variation in close distance calls of baboons may also arise from acoustic adaptations to environmental factors in order to counteract sound degradation. We teste…
Endocrinological correlates of male bimaturism in wild Bornean orangutans
Among primates, orangutans are unique in having pronounced male bimaturism leading to two fully adult morphs that differ in both physical appearance and behavior. While unflanged males have a female-like appearance, flanged males have the full suite of secondary sexual characteristics, including cheek flanges and a large throat sac. So far, hormonal correlates of arrested development in unflanged males and the expression of secondary sexual chara…
Modeling Primate Abundance in Complex Landscapes: A Case Study From the Udzungwa Mountains of Tanzania
Who is who matters—The effects of pseudoreplication in stable isotope analyses
Stable isotope analysis in free-ranging primates is a promising new avenue in reconstructing feeding niches and temporal dietary variation. Particularly, the large sample sizes obtained from non-invasively collected hair and fecal samples from nests of great apes offer great potential. However, analyzing repeated observations of the same individuals without controlling for potential differences among them means to "pseudoreplicate" and can lead t…
Social and demographic correlates of male androgen levels in wild white‐faced capuchin monkeys ( Cebus capucinus )
The Challenge Hypothesis, designed originally to explain the patterning of competitive behavior and androgen levels in seasonally breeding birds, predicts that males will increase their androgen levels in order to become more competitive in reproductive contexts. Here we test predictions derived from the Challenge Hypothesis in white-faced capuchin monkeys (Cebus capucinus), a species that has somewhat seasonal reproduction. We analyzed demograph…
Biology (32 works) · Primate Behavior and Ecology (31 works) · Ecology (21 works) · Demography (14 works) · Zoology (14 works) · Animal Behavior and Reproduction (13 works) · Wildlife Ecology and Conservation (13 works) · Geography (11 works) · Habitat (11 works) · Population (11 works)