Research
Behavioral research helps to answer important questions about optimal animal care and well-being, and improves our ability to meet the husbandry, social, and behavioral needs of the animals in our care. By analyzing behavior, researchers try to develop an understanding of animals’ learning processes, motivations, physical abilities, sensory adaptations and social structure. This information is then used to make decisions about managing animals. Working to understand orangutans’ sensory, cognitive, and physiological abilities can also be applied to conservation strategies, thereby benefiting orangutans in the wild as well.
Research using biomaterials is another important aspect, especially when such studies involve passive or voluntary collection of samples (e.g., urine, feces, hair, milk, recently even blood samples or blood pressure readings, etc.), or materials than can be collected opportunistically during scheduled anesthesia (e.g., body measurements taken during routine scheduled physical examination, collection of biological samples from apes not trained for voluntary collection, etc.).
Behavioral research helps to answer important questions about optimal animal care and well-being, and improves our ability to meet the husbandry, social, and behavioral needs of the animals in our care. By analyzing behavior, researchers try to develop an understanding of animals’ learning processes, motivations, physical abilities, sensory adaptations and social structure. This information is then used to make decisions about managing animals. Working to understand orangutans’ sensory, cognitive, and physiological abilities can also be applied to conservation strategies, thereby benefiting orangutans in the wild as well.
Research using biomaterials is another important aspect, especially when such studies involve passive or voluntary collection of samples (e.g., urine, feces, hair, milk, recently even blood samples or blood pressure readings, etc.), or materials than can be collected opportunistically during scheduled anesthesia (e.g., body measurements taken during routine scheduled physical examination, collection of biological samples from apes not trained for voluntary collection, etc.).
The SSP Research/Biomaterials Request Review Process
Research and biomaterials proposals submitted to the Orangutan SSP are reviewed by the SSP's Steering Committee and Advisors. Proposals are judged primarily on their relevance to the Orangutan SSP program. The reviewers' determination will be:
No Objection/Relevant to SSP;
No Objection/Not Relevant to SSP;
or
SSP Objection.
The SSP's determination does not compel individual zoos to participate, nor does it preclude participation. Many zoos require review by their own internal research approval process regardless of the SSP's stance. The SSP's determination is valid for three years from the date of notification, after which continuing proposals must be resubmitted for review.
The SSP's application form intentionally mirrors the Standardized Research Proposal form developed by the AZA's Research and Technology Committee.
Applicants will be notified of the Steering Committee's majority determination within 6 weeks of submission of a complete application.
Click here to download the Orangutan SSP Research Proposal Form.
Click here for Grant Funding information and Application
Why Submit Your Research Proposal to the SSP?
Some studies can be accomplished by collecting data on just a few individuals, and in those cases, researchers may choose to work directly with their local zoo for access to orangutans. Many research projects, however, benefit from the inclusion of data from a large number of individuals. In those cases, working through the Orangutan SSP can be of significant benefit to the scientist because of the broader awareness and encouragement of the SSP. Additionally, for some zoos, SSP review is a prerequisite to acceptance through their own internal research approval process. SSP review can also be beneficial in obtaining outside funding for research projects. Note, however, that the SSP's determination does not compel individual zoos to participate, nor does absence of SSP review preclude participation.
Current Projects
Each of the following research projects has been reviewed by the Steering Committee, and SSP-member zoos are encouraged to participate in these studies. Projects are updated on an annual basis for progress and status.
The Orangutan SSP supports the Great Ape Heart Project, an IMLS-funded project to design an innovative and coordinated national program to investigate ape cardiovascular disease (CVD) and establish uniform, state of the art cardiac diagnosis, treatment and prevention strategies for great ape CVD. Click here to learn more about the Great Ape Heart Project.
Determination of normal reference intervals for thyroid hormone serum concentrations in orangutans (Pongo sp.): Melissa Fayette, DVM (Indianapolis Zoo), Anneke Moresco, DVM, PhD (Reproductive Health Surveillance Program), Emily Vincent, DVM (The Ohio State University), Brian Petroff, DVM, PhD (Michigan State University), and Dalen Agnew (Michigan State University). Thyroid disease has been reported anecdotally in several orangutans within the SSP population; however, accurate diagnosis of these conditions is hindered by a paucity of published reference intervals for thyroid hormone serum concentrations in this species. Thyroid hormones play a critical role in regulation of growth, metabolism, and reproduction. Excess or deficiency in thyroid hormones may lead to the development of potentially life-threatening conditions such as hypertension, cardiovascular disease, and diabetes and can also result in infertility. Thus, timely detection and treatment of thyroid dysfunction is essential given its potential impact on overall health and breeding success of this critically endangered species. The goal of this study is to establish baseline reference intervals for thyroxine (T4), free-thyroxine (FT4), free triiodothyronine (T3) and thyroid stimulating hormone (TSH) in healthy orangutans using commercially available chemiluminescence immunoassays validated specifically for use in this species and to determine the influence of sex and age on thyroid hormone serum concentrations. (Reviewed September 2021)
Investigating the Composition of the Milk of Apes: Dr. Mike Power PhD, Mike Maslanka and Erin Stromberg, Smithsonian National Zoo. This is a continuation of ongoing research. The objective is to obtain longitudinal milk samples from apes (bonobos, chimpanzees, gorillas, orangutans, and gibbons), from shortly after birth until the female is no longer lactating, in order to further characterize the nutritional content of ape milk, continue investigating the milk microbiota of non-human primates, and learn more about the potential role of bioactive molecules in mother’s milk to regulate offspring physiology and metabolism (among other questions). Additional milk samples from females whose milk has not previously been collected are important to document the extent to which there are species-specific patterns and the extent of variation between females. To date, samples have been obtained from 3 orangutans and 7 lowland gorillas. We aim to receive samples from 10-12 individuals from each ape species in order to be able to fully characterize variation between females. Results of this work are shared widely for the benefit of zoos worldwide. Samples are available for collaborative research projects. (Renewed June 2021)
Exploring the microstructure and fracture resistance of tooth enamel from Pongo pygmaeus: Cameron Renteria (PhD Candidate, University of Washington), Izabela Carpenter (University of Washington), *Dwayne Arola, PhD (University of Washington). Tooth enamel requires tolerance to damage and resistance to fracture. In mammalian teeth, the microstructure of enamel prevents cracks at the tooth’s surface from causing tooth fracture. The secret to this quality is a special pattern of the enamel rod distribution known as decussation. Vogel et al. [2008] reported that the enamel of Pongo molar teeth exhibits an “optimized” microstructure that enables their diet to include harder and tougher materials without causing tooth fracture. That special quality could enable their teeth to endure the comparatively larger bite forces required for their diet relative to other mammals. This study examines the tooth enamel of Pongo and other orangutans using spectroscopy, microscopy and other tools to determine the composition, microstructure and mechanical properties relevant to the crack growth resistance. These efforts will provide new understanding of enamel microstructure in orangutans and could inspire the design of next generation engineering materials with an unparalleled level of damage tolerance. (Reviewed April 2021)
Development of a database of fetal ultrasound measurements for the creation of orangutan-specific (Pongo spp.) growth curves and determination of parturition dates: Current data is lacking in species specific fetal growth curves and gestation lengths for orangutans. Dr. Brittany Rizzo, along with Connie Warner, Dr. Joe Smith, and Dr. Ric Berlinski, is compiling existing fetal ultrasound and birth date information as well as gathering future information in the hopes of creating more accurate and species-specific fetal growth curves for orangutans. Data of this nature can benefit institutions via improved planning for their training and social structure changes. Additionally, in cases of animals that have had previous difficult births or emergency cesarean sections, accurate determination of gestational age for scheduling future cesarean sections can reduce the risk of complications for both the dam and the infant. Please click here for project description and information on participation; click here for contact information. (Renewed April 2021)
Great Ape Neuroscience Project: The goal of the Great Ape Neuroscience Project is to investigate the neurobiological basis of variation that distinguishes great apes from other primates, defines each great ape species as unique, and helps us to better understand humans’ place in nature. The Great Ape Neuroscience Project originated as an extension of the Great Ape Aging Project (funded by the National Institute on Aging of the National Institutes of Health). The Great Ape Aging Project was conceived of as a means of adding scientific value to elderly apes in captivity. Medical scientists studying the causes of neurodegenerative diseases such as Alzheimer’s and Parkinson’s diseases expressed interest in studies of brain and behavior in great apes to determine whether or not the same neurodegenerative processes occurred in them as in afflicted humans. The convergence of these interests and needs led to the development of the Great Ape Aging Project in 1997. This project seeks whole fixed brains from great apes (and other primates) at necropsy. Several documents describe the project and its requirements: Great Ape Neuroscience Project 2011 Progress Report; Project description; TAG project approval letter; Detailed brain collection and submission instructions. Bibliography of articles related to this project. Contact: William Hopkins or Chet Sherwood (Renewed March 2021)
Humor and teasing in great apes: Isabelle Laumer, PhD (Department of Anthropology, UCLA), Prof. Erica Cartmill (Department of Anthropology, UCLA). This study explores the forms and functions of teasing in zoo-living great apes, with a particular focus on playful teasing. Recent developmental studies suggest that non-verbal “playful teasing” is already visible in human infants in the first year of life. The occurrence of playful teasing in preverbal infants suggests that language is not a prerequisite for this behavior and, thus, that it might be present in our closest living relatives. We aim to gather information about the prevalence and types of teasing in zoo-living apes through a questionnaire for ape keepers sent to selected North American and European zoos. The purpose of this study is to systematically assess and identify different forms of teasing behaviors, in which apes try to provoke a social reaction from others. These interactions might resemble games, teasing, harassment, or surprising each other. Furthermore, we hope to better understand which animals (e.g. age classes) typically perform provocative behavior and to whom it is directed. We are also interested in how apes respond to teasing from others. Developing a more complete understanding of the dynamics of positive and negative teasing behaviors will contribute to zoos’ goals of better assessing and managing the complex social dynamics of zoo-housed primates and the findings of this study will make important contributions to comparative psychology and evolutionary biology. (Reviewed January 2021)
Tannin-Binding Salivary Proteins in Apes: William Aguado (PhD Candidate, Rutgers University), Meredith Bastian (Proceedings of the National Academy of Sciences) Erin Vogel, PhD (Rutgers University & Tuanan Orangutan Research Project). Foraging primates are faced with acquiring adequate nutrition from plants while simultaneously overcoming the challenges posed by plant secondary metabolites (PSMs) – the often toxic, unpalatable, or otherwise harmful chemical compounds that plants produce. PSMs are considered a selective force acting on primate physiology and primates should evolve physiological mechanisms for combatting commonly encountered PSMs. As part of a larger project exploring the relationship between PSMs and the feeding behavior, nutrition, and health of Bornean orangutans (Pongo pygmaeus wurmbii), this research examines whether orangutans have physiological adaptations to a diet rich in tannins – a common class of PSMs known for being toxic and inhibiting digestion. Our goal is to collect saliva from orangutans housed at AZA accredited zoos to see if, and to what extent, orangutans produce tannin-binding salivary proteins as a defense against tannins. We are particularly interested in proline-rich-salivary proteins (PRPs), which are thought to be produced in the saliva of some mammals to bind tannins and decrease their ability to inhibit protein digestion. Once saliva is collected, we will screen for PRPs, measure their abundance in orangutan saliva, and measure their tannin-binding capacity. Knowing the extent to which orangutans produce PRPs will help to explain orangutan diet selection in the wild and increase our understanding of orangutan physiology. (Reviewed December 2020)
The influence of plant secondary metabolites on diet selection, nutrition, and health of wild Bornean Orangutans: William Aguado (PhD Candidate, Rutgers University) and Erin Vogel, PhD (Rutgers University & Tuanan Orangutan Research Project). Plant secondary metabolites (PSMs)—the toxic, unpalatable, or otherwise harmful chemical compounds that are produced in plants—are thought to play an important role in determining what primates can and do eat. Orangutans presumably encounter such compounds in their biodiverse environments, yet the role PSMs play in their nutritional ecology is poorly understood. This study examines how a common class of PSM called tannins, inhibits nutrient digestion and influences foraging behavior of Bornean orangutans at the site of Tuanan, in Central Kalimantan, Indonesia. We use behavioral observation, nutritional analysis of plant foods, and urinary biomarkers of nutritional stress to answer these questions. Gaining a better understanding of the chemical predictors of orangutan diet selection can help shed light on their ecology and evolution, contribute to our nutritional prescriptions for these apes in captivity, and help to identify key resources that support wild orangutan populations. (Approved October 2020)
Retrospective assessment of peri-anesthetic mortality and associated risk factors of great apes among zoological collections in the United States over a 10 year period: Julie Balko, VMD, DACVAA (NC State University, College of Veterinary Medicine), Sathya Chinnadurai, DVM, Ms, DACZM, DACVAA, DACAW (St. Louis Zoo), and Jb Minter, MS, DVM, DACZM (North Carolina Zoo). This project will retrospectively assess peri–anesthetic mortality risk and associated risk factors of great ape species among zoological collections within the United States over a 10 year period. Great apes are commonly found in professional care settings in the United States and are frequently anesthetized for diagnostic and therapeutic purposes. While great ape peri–anesthetic mortality risk has been investigated among zoological collections in the UK and Ireland, no multi-institutional studies have been conducted among collections in the United States and the few published single institution studies were conducted greater than 20 years ago. As great ape anesthetic management has changed greatly within this time frame (eg, anesthetic drug protocols, anesthetic monitoring capabilities), investigation of current peri–anesthetic mortality risk and associated risk factors among multiple zoological collections within the United States is imperative. This data is of immense clinical relevance and will not only help guide anesthetic management of great ape species but will ultimately help reduce anesthetic morbidity and mortality of these endangered animals. (Reviewed June 2020)
Orangutan fecal microbiome analysis: Stephanie McCain, DVM, Dipl ACZM (Birmingham Zoo), Richard Sim, DVM, Dipl ACZM (Oregon Zoo), and Casey Morrow, PhD (University of Alabama, Birmingham). An inordinate number of zoo housed orangutans have either chronic constipation or chronic diarrhea, with an underlying cause rarely identified. (Nancy Lung, personnal comm.) Many zoos must manage one or both of these conditions, regardless of diet fed, illustrating the need to have a better understanding of orangutan GI health. The goal of this study is to understand how the gut microbe community structure correlates with and can influence the health and behavior of zoo-housed orangutans. In order to accomplish this goal, we plan to perform microbiome analysis on fecal samples from all individual orangutans housed in the United States and evaluate these results against diet, fecal consistency, and pedigree. (Approved January 2020)
Growth and Development in Captive Juvenile Orangutans Faye Harwell (PhD Candidate at Boston University) & Cheryl Knott, PhD (Boston University & Gunung Palung Orangutan Project). Next to humans, orangutans have the slowest life history amongst primates starting with a long juvenile period. Despite many years of study, little is known about the timing of development in orangutans, the relationship between energetics and growth, the association between sex steroids and developmental events, and the relationship between flanging and skeletal growth. This study will examine growth and development in captive orangutans and fill some of these gaps in our knowledge of this critically endangered great ape. We hope to study the process of flanging for participants that begin flange development during data collection. Methods for this study include collecting urine samples for hormone analyses, taking photographs of the participants’ forearms and facial profiles to estimate growth, and examining historical weight records to assess changes in overall body size. Please contact Faye Harwell or Cheryl Knott with any questions or inquiries about the study. (Approved June 2019)
Investigating a Genetic Basis for Chronic Respiratory Disease in orangutans The objective of this study is to establish whether there is a genetic cause for orangutan respiratory disease syndrome (ORDS), the chronic lung and sinus disease that decreases the quality of life and increases the rate of death in orangutans. In our previous study, we identified a nonsense mutation (c.484A>T) in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene in heterozygosity in an asymptomatic male and in his sire and offspring. We further demonstrated that the resulting protein from this nonsense mutation was absent when it was introduced in HEK293 cells, and that c.484A>T messenger RNA was severed reduced in nasal epithelial cells from the orangutan, suggesting that this mutation is potentially lethal if combined with another severe CFTR mutation. Finally, we demonstrated the lack of CFTR mutations in an affected male and his affected father. Link to our publication in the American Journal of Primatology is here: https://onlinelibrary.wiley.com/doi/abs/10.1002/ajp.23097 These results suggest that whole genome sequencing could help us better understand if gene abnormalities track with disease. Dr. Taylor-Cousar will carefully review the medical and pedigree records of all orangutans with chronic sinopulmonary disease and those of his/her living and deceased relatives in order to correctly phenotype ORDS-affected and unaffected orangutans. We will collect blood and tissue samples from orangutans at participating zoos for analysis. If it is established that chronic respiratory disease in orangutans is a result of gene abnormalities, this information can be used to guide the use of therapies and breeding decisions in the orangutan population. This research is being led by Dr. Jennifer Taylor-Cousar in collaboration with colleagues at Johns Hopkins University. For questions regarding project participation, please contact Dr. Taylor-Cousar (Renewed March 2019)
Retrospective Classification and Management Assessment of Canine Fractures in Captive Managed Populations of Great Apes: Jill Moyse, Curator of Primates, Lincoln Park Zoo. At this time, it is unknown how many individual great apes in the captive population have broken, fractured and or cracked canine teeth. As several approaches for treatment or repair are possible, it is not known which of these injuries correlate best with the available management options. Long-term effects of no treatment are not predictable. The retrospective project will survey the captive managed great ape population to assess the occurrence of injuries and what treatment was provided to the animal. Zoo veterinarians will be surveyed to document any great apes in their collection that have any incidents of breakage, cracked or fracture of the canine teeth in the last 10 years. We anticipate majority to full participation from the SSP institutions that house great apes and will be able to compile an inventory of all animals that currently have canine fractures, breaks or cracks, the treatment they received and if any common risk factors are associated with the canine fractures. With this information, it is anticipated that prospective guidance of treatment options can be provided to institutions, veterinarians and the great ape SSP when animals present a fracture, break or cracked canine. (Approved November 2018)
Captive Orangutan Dentition Emergence: Felicity Oram is investigating tooth emergence in orangutans. The specific primary objective is to provide a comprehensive updated tooth emergence chart for both species. The need is for more consistent and specific age assignment to better serve husbandry and rehabilitation of orphans and to help build stronger cases for enforcement of existing laws that protect these endangered species in range countries. Additionally, this will provide zoos with a useful updated resource of baseline normals for tooth emergence. Since orangutans are a slow-growing long-lived species of a semi-solitary nature many zoos hold only a few individuals so the benefit of accumulated knowledge in a simple format will be useful for husbandry and veterinary care of zoo residents. Please review the project proposal and the report form for more information; click here for contact information. (Approved June 2013)
Research and biomaterials proposals submitted to the Orangutan SSP are reviewed by the SSP's Steering Committee and Advisors. Proposals are judged primarily on their relevance to the Orangutan SSP program. The reviewers' determination will be:
No Objection/Relevant to SSP;
No Objection/Not Relevant to SSP;
or
SSP Objection.
The SSP's determination does not compel individual zoos to participate, nor does it preclude participation. Many zoos require review by their own internal research approval process regardless of the SSP's stance. The SSP's determination is valid for three years from the date of notification, after which continuing proposals must be resubmitted for review.
The SSP's application form intentionally mirrors the Standardized Research Proposal form developed by the AZA's Research and Technology Committee.
Applicants will be notified of the Steering Committee's majority determination within 6 weeks of submission of a complete application.
Click here to download the Orangutan SSP Research Proposal Form.
Click here for Grant Funding information and Application
Why Submit Your Research Proposal to the SSP?
Some studies can be accomplished by collecting data on just a few individuals, and in those cases, researchers may choose to work directly with their local zoo for access to orangutans. Many research projects, however, benefit from the inclusion of data from a large number of individuals. In those cases, working through the Orangutan SSP can be of significant benefit to the scientist because of the broader awareness and encouragement of the SSP. Additionally, for some zoos, SSP review is a prerequisite to acceptance through their own internal research approval process. SSP review can also be beneficial in obtaining outside funding for research projects. Note, however, that the SSP's determination does not compel individual zoos to participate, nor does absence of SSP review preclude participation.
Current Projects
Each of the following research projects has been reviewed by the Steering Committee, and SSP-member zoos are encouraged to participate in these studies. Projects are updated on an annual basis for progress and status.
The Orangutan SSP supports the Great Ape Heart Project, an IMLS-funded project to design an innovative and coordinated national program to investigate ape cardiovascular disease (CVD) and establish uniform, state of the art cardiac diagnosis, treatment and prevention strategies for great ape CVD. Click here to learn more about the Great Ape Heart Project.
Determination of normal reference intervals for thyroid hormone serum concentrations in orangutans (Pongo sp.): Melissa Fayette, DVM (Indianapolis Zoo), Anneke Moresco, DVM, PhD (Reproductive Health Surveillance Program), Emily Vincent, DVM (The Ohio State University), Brian Petroff, DVM, PhD (Michigan State University), and Dalen Agnew (Michigan State University). Thyroid disease has been reported anecdotally in several orangutans within the SSP population; however, accurate diagnosis of these conditions is hindered by a paucity of published reference intervals for thyroid hormone serum concentrations in this species. Thyroid hormones play a critical role in regulation of growth, metabolism, and reproduction. Excess or deficiency in thyroid hormones may lead to the development of potentially life-threatening conditions such as hypertension, cardiovascular disease, and diabetes and can also result in infertility. Thus, timely detection and treatment of thyroid dysfunction is essential given its potential impact on overall health and breeding success of this critically endangered species. The goal of this study is to establish baseline reference intervals for thyroxine (T4), free-thyroxine (FT4), free triiodothyronine (T3) and thyroid stimulating hormone (TSH) in healthy orangutans using commercially available chemiluminescence immunoassays validated specifically for use in this species and to determine the influence of sex and age on thyroid hormone serum concentrations. (Reviewed September 2021)
Investigating the Composition of the Milk of Apes: Dr. Mike Power PhD, Mike Maslanka and Erin Stromberg, Smithsonian National Zoo. This is a continuation of ongoing research. The objective is to obtain longitudinal milk samples from apes (bonobos, chimpanzees, gorillas, orangutans, and gibbons), from shortly after birth until the female is no longer lactating, in order to further characterize the nutritional content of ape milk, continue investigating the milk microbiota of non-human primates, and learn more about the potential role of bioactive molecules in mother’s milk to regulate offspring physiology and metabolism (among other questions). Additional milk samples from females whose milk has not previously been collected are important to document the extent to which there are species-specific patterns and the extent of variation between females. To date, samples have been obtained from 3 orangutans and 7 lowland gorillas. We aim to receive samples from 10-12 individuals from each ape species in order to be able to fully characterize variation between females. Results of this work are shared widely for the benefit of zoos worldwide. Samples are available for collaborative research projects. (Renewed June 2021)
Exploring the microstructure and fracture resistance of tooth enamel from Pongo pygmaeus: Cameron Renteria (PhD Candidate, University of Washington), Izabela Carpenter (University of Washington), *Dwayne Arola, PhD (University of Washington). Tooth enamel requires tolerance to damage and resistance to fracture. In mammalian teeth, the microstructure of enamel prevents cracks at the tooth’s surface from causing tooth fracture. The secret to this quality is a special pattern of the enamel rod distribution known as decussation. Vogel et al. [2008] reported that the enamel of Pongo molar teeth exhibits an “optimized” microstructure that enables their diet to include harder and tougher materials without causing tooth fracture. That special quality could enable their teeth to endure the comparatively larger bite forces required for their diet relative to other mammals. This study examines the tooth enamel of Pongo and other orangutans using spectroscopy, microscopy and other tools to determine the composition, microstructure and mechanical properties relevant to the crack growth resistance. These efforts will provide new understanding of enamel microstructure in orangutans and could inspire the design of next generation engineering materials with an unparalleled level of damage tolerance. (Reviewed April 2021)
Development of a database of fetal ultrasound measurements for the creation of orangutan-specific (Pongo spp.) growth curves and determination of parturition dates: Current data is lacking in species specific fetal growth curves and gestation lengths for orangutans. Dr. Brittany Rizzo, along with Connie Warner, Dr. Joe Smith, and Dr. Ric Berlinski, is compiling existing fetal ultrasound and birth date information as well as gathering future information in the hopes of creating more accurate and species-specific fetal growth curves for orangutans. Data of this nature can benefit institutions via improved planning for their training and social structure changes. Additionally, in cases of animals that have had previous difficult births or emergency cesarean sections, accurate determination of gestational age for scheduling future cesarean sections can reduce the risk of complications for both the dam and the infant. Please click here for project description and information on participation; click here for contact information. (Renewed April 2021)
Great Ape Neuroscience Project: The goal of the Great Ape Neuroscience Project is to investigate the neurobiological basis of variation that distinguishes great apes from other primates, defines each great ape species as unique, and helps us to better understand humans’ place in nature. The Great Ape Neuroscience Project originated as an extension of the Great Ape Aging Project (funded by the National Institute on Aging of the National Institutes of Health). The Great Ape Aging Project was conceived of as a means of adding scientific value to elderly apes in captivity. Medical scientists studying the causes of neurodegenerative diseases such as Alzheimer’s and Parkinson’s diseases expressed interest in studies of brain and behavior in great apes to determine whether or not the same neurodegenerative processes occurred in them as in afflicted humans. The convergence of these interests and needs led to the development of the Great Ape Aging Project in 1997. This project seeks whole fixed brains from great apes (and other primates) at necropsy. Several documents describe the project and its requirements: Great Ape Neuroscience Project 2011 Progress Report; Project description; TAG project approval letter; Detailed brain collection and submission instructions. Bibliography of articles related to this project. Contact: William Hopkins or Chet Sherwood (Renewed March 2021)
Humor and teasing in great apes: Isabelle Laumer, PhD (Department of Anthropology, UCLA), Prof. Erica Cartmill (Department of Anthropology, UCLA). This study explores the forms and functions of teasing in zoo-living great apes, with a particular focus on playful teasing. Recent developmental studies suggest that non-verbal “playful teasing” is already visible in human infants in the first year of life. The occurrence of playful teasing in preverbal infants suggests that language is not a prerequisite for this behavior and, thus, that it might be present in our closest living relatives. We aim to gather information about the prevalence and types of teasing in zoo-living apes through a questionnaire for ape keepers sent to selected North American and European zoos. The purpose of this study is to systematically assess and identify different forms of teasing behaviors, in which apes try to provoke a social reaction from others. These interactions might resemble games, teasing, harassment, or surprising each other. Furthermore, we hope to better understand which animals (e.g. age classes) typically perform provocative behavior and to whom it is directed. We are also interested in how apes respond to teasing from others. Developing a more complete understanding of the dynamics of positive and negative teasing behaviors will contribute to zoos’ goals of better assessing and managing the complex social dynamics of zoo-housed primates and the findings of this study will make important contributions to comparative psychology and evolutionary biology. (Reviewed January 2021)
Tannin-Binding Salivary Proteins in Apes: William Aguado (PhD Candidate, Rutgers University), Meredith Bastian (Proceedings of the National Academy of Sciences) Erin Vogel, PhD (Rutgers University & Tuanan Orangutan Research Project). Foraging primates are faced with acquiring adequate nutrition from plants while simultaneously overcoming the challenges posed by plant secondary metabolites (PSMs) – the often toxic, unpalatable, or otherwise harmful chemical compounds that plants produce. PSMs are considered a selective force acting on primate physiology and primates should evolve physiological mechanisms for combatting commonly encountered PSMs. As part of a larger project exploring the relationship between PSMs and the feeding behavior, nutrition, and health of Bornean orangutans (Pongo pygmaeus wurmbii), this research examines whether orangutans have physiological adaptations to a diet rich in tannins – a common class of PSMs known for being toxic and inhibiting digestion. Our goal is to collect saliva from orangutans housed at AZA accredited zoos to see if, and to what extent, orangutans produce tannin-binding salivary proteins as a defense against tannins. We are particularly interested in proline-rich-salivary proteins (PRPs), which are thought to be produced in the saliva of some mammals to bind tannins and decrease their ability to inhibit protein digestion. Once saliva is collected, we will screen for PRPs, measure their abundance in orangutan saliva, and measure their tannin-binding capacity. Knowing the extent to which orangutans produce PRPs will help to explain orangutan diet selection in the wild and increase our understanding of orangutan physiology. (Reviewed December 2020)
The influence of plant secondary metabolites on diet selection, nutrition, and health of wild Bornean Orangutans: William Aguado (PhD Candidate, Rutgers University) and Erin Vogel, PhD (Rutgers University & Tuanan Orangutan Research Project). Plant secondary metabolites (PSMs)—the toxic, unpalatable, or otherwise harmful chemical compounds that are produced in plants—are thought to play an important role in determining what primates can and do eat. Orangutans presumably encounter such compounds in their biodiverse environments, yet the role PSMs play in their nutritional ecology is poorly understood. This study examines how a common class of PSM called tannins, inhibits nutrient digestion and influences foraging behavior of Bornean orangutans at the site of Tuanan, in Central Kalimantan, Indonesia. We use behavioral observation, nutritional analysis of plant foods, and urinary biomarkers of nutritional stress to answer these questions. Gaining a better understanding of the chemical predictors of orangutan diet selection can help shed light on their ecology and evolution, contribute to our nutritional prescriptions for these apes in captivity, and help to identify key resources that support wild orangutan populations. (Approved October 2020)
Retrospective assessment of peri-anesthetic mortality and associated risk factors of great apes among zoological collections in the United States over a 10 year period: Julie Balko, VMD, DACVAA (NC State University, College of Veterinary Medicine), Sathya Chinnadurai, DVM, Ms, DACZM, DACVAA, DACAW (St. Louis Zoo), and Jb Minter, MS, DVM, DACZM (North Carolina Zoo). This project will retrospectively assess peri–anesthetic mortality risk and associated risk factors of great ape species among zoological collections within the United States over a 10 year period. Great apes are commonly found in professional care settings in the United States and are frequently anesthetized for diagnostic and therapeutic purposes. While great ape peri–anesthetic mortality risk has been investigated among zoological collections in the UK and Ireland, no multi-institutional studies have been conducted among collections in the United States and the few published single institution studies were conducted greater than 20 years ago. As great ape anesthetic management has changed greatly within this time frame (eg, anesthetic drug protocols, anesthetic monitoring capabilities), investigation of current peri–anesthetic mortality risk and associated risk factors among multiple zoological collections within the United States is imperative. This data is of immense clinical relevance and will not only help guide anesthetic management of great ape species but will ultimately help reduce anesthetic morbidity and mortality of these endangered animals. (Reviewed June 2020)
Orangutan fecal microbiome analysis: Stephanie McCain, DVM, Dipl ACZM (Birmingham Zoo), Richard Sim, DVM, Dipl ACZM (Oregon Zoo), and Casey Morrow, PhD (University of Alabama, Birmingham). An inordinate number of zoo housed orangutans have either chronic constipation or chronic diarrhea, with an underlying cause rarely identified. (Nancy Lung, personnal comm.) Many zoos must manage one or both of these conditions, regardless of diet fed, illustrating the need to have a better understanding of orangutan GI health. The goal of this study is to understand how the gut microbe community structure correlates with and can influence the health and behavior of zoo-housed orangutans. In order to accomplish this goal, we plan to perform microbiome analysis on fecal samples from all individual orangutans housed in the United States and evaluate these results against diet, fecal consistency, and pedigree. (Approved January 2020)
Growth and Development in Captive Juvenile Orangutans Faye Harwell (PhD Candidate at Boston University) & Cheryl Knott, PhD (Boston University & Gunung Palung Orangutan Project). Next to humans, orangutans have the slowest life history amongst primates starting with a long juvenile period. Despite many years of study, little is known about the timing of development in orangutans, the relationship between energetics and growth, the association between sex steroids and developmental events, and the relationship between flanging and skeletal growth. This study will examine growth and development in captive orangutans and fill some of these gaps in our knowledge of this critically endangered great ape. We hope to study the process of flanging for participants that begin flange development during data collection. Methods for this study include collecting urine samples for hormone analyses, taking photographs of the participants’ forearms and facial profiles to estimate growth, and examining historical weight records to assess changes in overall body size. Please contact Faye Harwell or Cheryl Knott with any questions or inquiries about the study. (Approved June 2019)
Investigating a Genetic Basis for Chronic Respiratory Disease in orangutans The objective of this study is to establish whether there is a genetic cause for orangutan respiratory disease syndrome (ORDS), the chronic lung and sinus disease that decreases the quality of life and increases the rate of death in orangutans. In our previous study, we identified a nonsense mutation (c.484A>T) in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene in heterozygosity in an asymptomatic male and in his sire and offspring. We further demonstrated that the resulting protein from this nonsense mutation was absent when it was introduced in HEK293 cells, and that c.484A>T messenger RNA was severed reduced in nasal epithelial cells from the orangutan, suggesting that this mutation is potentially lethal if combined with another severe CFTR mutation. Finally, we demonstrated the lack of CFTR mutations in an affected male and his affected father. Link to our publication in the American Journal of Primatology is here: https://onlinelibrary.wiley.com/doi/abs/10.1002/ajp.23097 These results suggest that whole genome sequencing could help us better understand if gene abnormalities track with disease. Dr. Taylor-Cousar will carefully review the medical and pedigree records of all orangutans with chronic sinopulmonary disease and those of his/her living and deceased relatives in order to correctly phenotype ORDS-affected and unaffected orangutans. We will collect blood and tissue samples from orangutans at participating zoos for analysis. If it is established that chronic respiratory disease in orangutans is a result of gene abnormalities, this information can be used to guide the use of therapies and breeding decisions in the orangutan population. This research is being led by Dr. Jennifer Taylor-Cousar in collaboration with colleagues at Johns Hopkins University. For questions regarding project participation, please contact Dr. Taylor-Cousar (Renewed March 2019)
Retrospective Classification and Management Assessment of Canine Fractures in Captive Managed Populations of Great Apes: Jill Moyse, Curator of Primates, Lincoln Park Zoo. At this time, it is unknown how many individual great apes in the captive population have broken, fractured and or cracked canine teeth. As several approaches for treatment or repair are possible, it is not known which of these injuries correlate best with the available management options. Long-term effects of no treatment are not predictable. The retrospective project will survey the captive managed great ape population to assess the occurrence of injuries and what treatment was provided to the animal. Zoo veterinarians will be surveyed to document any great apes in their collection that have any incidents of breakage, cracked or fracture of the canine teeth in the last 10 years. We anticipate majority to full participation from the SSP institutions that house great apes and will be able to compile an inventory of all animals that currently have canine fractures, breaks or cracks, the treatment they received and if any common risk factors are associated with the canine fractures. With this information, it is anticipated that prospective guidance of treatment options can be provided to institutions, veterinarians and the great ape SSP when animals present a fracture, break or cracked canine. (Approved November 2018)
Captive Orangutan Dentition Emergence: Felicity Oram is investigating tooth emergence in orangutans. The specific primary objective is to provide a comprehensive updated tooth emergence chart for both species. The need is for more consistent and specific age assignment to better serve husbandry and rehabilitation of orphans and to help build stronger cases for enforcement of existing laws that protect these endangered species in range countries. Additionally, this will provide zoos with a useful updated resource of baseline normals for tooth emergence. Since orangutans are a slow-growing long-lived species of a semi-solitary nature many zoos hold only a few individuals so the benefit of accumulated knowledge in a simple format will be useful for husbandry and veterinary care of zoo residents. Please review the project proposal and the report form for more information; click here for contact information. (Approved June 2013)
Completed Projects
The Giant Panda Management as a Model for the Malayan Tiger and Bornean Orang Utan Management in Malaysia: Rohana Jani, PhD (University of Malaya), Noor Hashida Hashim, PhD (University of Malaya), Mohd. Tajuddin Abdullah, PhD (University Malaysia Terengganu) and Dennis Ten Choon Yung (University of Malaya/PERHILITAN). The Giant Panda has been placed under the Endangered red list status since 1990.Its status has been down listed from Endangered to Vulnerable in 2016. The conservation works on the Giant Panda is indeed a successful conservation effort. While both IUCN Red List of Threatened Species status for the Malayan Tiger and Bornean Orang Utan have been elevated from Endangered to Critically Endangered in 2015 and 2014. Currently, the Giant Panda conservation model is proven as the successful wildlife conservation model; an in-depth adaption is needed to enable such model to be applied to other threatened species to ensure the model benefited to the targeted species. We seek to understand the Giant Panda conservation management and the possibility that the captive Giant Panda conservation management model may contribute to the conservation management of Malayan Tiger and Bornean Orang Utan. The survey exercise will be distributed to animal captive facilities. The outcome of the study is potentially contributed to the country zoo management and captive wildlife management.
A survey of the prevalence and perceived efficacy of biofloors in great ape exhibits within AZA zoos: Jill Moyse, Curator of Primates, Lincoln Park Zoo. This research project will survey AZA institutions that house great apes to investigate the type of biofloor, if any, the animals have access to throughout the day and overnight. The survey will look at the prevalence of bio floors and the decisions made to provide bio floors from a management perspective. By comparing the attitudes and experiences of institutions that have biofloors to those that do not, we hope to elucidate what the motivations are for institutions to install them as well as what the barriers are to including biofloors in the design of new buildings or the refurbishment of existing exhibits. It is expected that cost and concerns over hygiene will represent common barriers, but we also anticipate that responses from intuitions that have biofloors in their exhibit will dispel such concerns.
A search for chemical signals in orang-utans: Male orangutan cheek pads are frequently hypothesised to have arisen through sexual selection, influenced by female preference or by male-male competition. However, their potential role in attracting females is not yet fully understood – nor is their potential role in suppressing development in unflanged males. In this preliminary study, Dr Graham L Banes, Professor Tom E Goodwin (Hendrix College) and Melanie Bond (National Zoo, retired) are using use solid phase dynamic extraction (SPDE) gas chromatography mass spectrometry (GC-MS) to identify volatile organic compounds that may emanate from orang-utan cheek pads. The research was featured on the PBS documentary, “Sex in the Wild: Orangutans”.
Variation in Vocal Repertoires of Wild and Captive Orangutans: Although most research on great ape vocalizations has been on chimpanzees, recent field research has produced a catalogue of a wide variety of orangutan vocalizations. Geographic variation in orangutan vocalizations has been identified both within call type and in the presence of certain vocalizations among wild populations. This study aims to catalogue vocal recordings collected across AZA zoo-housed orangutan collections and compare these to those previously documented in the wild. We are especially interested in the context of vocalizations, in novel vocalizations, and in the extent to which keepers can identify the meaning of the vocalizations they hear and record. Please click here for project description and information on participation; click here for contact information.
Respiratory Disease in the North American Captive Orangutan Population: Megan K. Fox of the Los Angeles Zoo and Botanical Gardens and Graduate Student, Evolutionary Anthropology at California State University, Fullerton. This project aims to identify some of the factors that influence the presence of respiratory disease in the North American captive orangutan population. Understanding if there are species differences in the prevalence of disease between the Sumatran and Bornean orangutan, between the sexes, between certain age classes, and between individuals at various developmental stages will provide valuable information and assist in the management of these species. This project also aims to identify other factors that may influence the onset of disease, such as weight, body condition, family history, rearing history, stress events, and environmental factors. Additionally, this project will provide information on the types of symptoms most commonly experienced that will also contribute to the possible early treatment and diagnoses of respiratory disease in captive orangutans. Identifying the risk factors involved will greatly enhance the ability for zoological institutions to act preemptively to treat disease which can ultimately assist in the overall care, management, and survivability of the individuals involved and hence the population as a whole. Contact Megan Fox here.
Insulin Resistance in Old World Primates: Dr. Elena Less of the Cleveland Metroparks Zoo is studying biomarkers of insulin resistance over time in several primate species, orangutans being the representative for apes. Dr. Less’s goal is to determine the effect of increasing age/time spent in captivity on insulin, glucose, cholesterol and triglycerides in banked serum samples from orangutans, Hamadryas baboons, mandrills, ring-tailed lemurs, and red ruffed lemurs. Click here for project description and information on participation; click here for contact information. PENDING ANALYSIS
Important Diseases of Rehabilitant Orangutans: Clinical Aspects of Epidemiology, Diagnosis and Treatment: The Central Kalimantan Orangutan Reintroduction Project of the Borneo Orangutan Survival Foundation at Nyaru Menteng (BOS-NM) holds the largest population of captive orangutans in the world, and associated health and veterinary records over a number of years. Analysis of the data contained within the clinic records, along with some investigative procedures, could fill in a number of knowledge-gaps, and contribute to the health and welfare of captive orangutans not only within BOS-NM, but across the world. Rosalie Dench is working to summarize retrospectively the incidence of orangutan diseases at BOS-NM and establish normal reference ranges for body weight and blood results for the population, which can act as a baseline for analyses, as well as evaluate current diagnostic methods in more detail for several diseases of significance. Click here for more detail on this project; click here for contact information. Work on TB testing, Air Sacculitis Risk Factors and normal ranges for orangutan bodyweight and haematology parameters has already been completed; please contact Rosalie Dench for further information.
Thyroid histology in orangutans with non‐congenital thyroid dysfunction, led by Dr. Sandra M. McLachlan of Cedars‐Sinai Medical Center in Los Angeles. This project investigated thyroid dysfunction in great apes by examining thyroid hormone levels and TSH in all nonhuman great ape genera including adults, adolescents, and infants, and establishing a thyroid hormone and TSH database in orangutans, gorillas, chimpanzees, and bonobos (447 individuals). The most striking differences found between these 4 great ape genera were greatly reduced FT4 and FT3 levels in orangutans and gorillas, and elevated TSH levels in gorillas, compared with chimpanzees and bonobos. In addition, autoantibodies to Tg and TPO were detectable in only 2.6% of adult great apes, significantly lower than the approximately 10% in humans. No great apes with thyroid autoantibodies exhibited thyroid dysfunction and neither thyroid autoantibodies nor thyroid lymphocytic infiltration were present in hypothyroid great apes. The researchers also concluded that hypothyroidism in the closest surviving human relatives may involve dietary components including goitrogens but is unrelated to thyroid autoimmunity. Click here to read the Endocrinology article detailing this work.
Cataloging Blood Types for SSP Populations of Great Apes, led by Kathryn Gamble and Jill Moyse, Lincoln Park Zoo. In humans and domestic mammals, blood typing plays an important role in providing excellent medical care in critical care situations. It has been repeatedly demonstrated that humans and great apes have conserved identities within the standard blood typing categories of A-B-O and D(Rh factor). Development of simple table-top laboratory techniques to identify these most basic of blood groups in human patients may be applied to similar benefit in the great ape species. Click here to read the Zoo Biology article detailing this work.
Jaw Gape in Primates, William Hylander, Duke Lemur Center. This project is part of a broad-based comparative study on feeding adaptations in anthropoid primates. There may be important morphological differences in terms of jaw mechanics between orangutans from Borneo as compared to those from Sumatra. If these supposed differences prove to be significant, this will indicate important morphological differences in terms of orangutan jaw-muscle architecture. This in turn is likely related to differences in feeding ecology. This project is now complete and data are being prepared for publication; results will be posted here when available.
Factors influencing male orang-utan reproductive success, Dr. Graham L. Banes, Max Planck Institute for Evolutionary Anthropology. Male orang-utans exhibit one of two physical forms: dominant males develop large 'cheek pads' on their faces, while socially subordinate males do not. The purpose of these ornaments has long been poorly understood. Though cheek pads are hypothesised to make dominant males more attractive to females, thus resulting in greater reproductive success, males without them are also known to have fathered offspring in the wild and in zoos — so why develop cheek pads if you can father offspring without them? A team led by Dr Graham L Banes of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, performed paternity testing of orang-utans at Camp Leakey in Tanjung Puting National Park, Indonesia, to see if the dominant male — Kusasi — was more reproductively successful than his rivals. Not only did Kusasi father almost all of the offspring born during his period of dominance, other males typically only achieved conceptions at the beginning and end of Kusasi's reign, when the dominance hierarchy was potentially unstable. The authors concluded that male bimaturism is likely to be an evolutionarily stable strategy, in which non-cheek-padded males simply bide their time until periods of rank instability. The methods for genetic analyses used in this research, which was published in September 2015 in the journal Behavioral Ecology and Sociobiology, were developed using faecal samples from the Los Angeles Zoo and Botanical Gardens, CA, St Paul's Como Zoo and Conservatory, MN, and Henry Vilas Zoo in Madison, WI. The study was featured by The Washington Post, Discovery News and The Daily Mail, and profiled on Serious Science. Preliminary findings were originally presented at the 9th Annual Orangutan SSP Husbandry Workshop at the Los Angeles Zoo and Botanical Gardens in August 2013.
Cytokine Production and Urinary Excretion in the Orangutan: Drs. Lyle Moldawer and Erin Vogel are investigating the hypothesis that a high degree of endotoxin-responsiveness and cytokine production is shared by orangutans and humans. Their study seeks (1) to determine cross-reactivity among orangutan cytokines and human immunoassay reagents, (2) to determine ex vivo cytokine production to bacterial endotoxin by whole blood obtained from orangutans, and (3) to measure hemopexin and other acute phase reactant proteins that bind endotoxin (LBP, BPI) in the plasma of orangutan. Click here for project description and information on participation; click here for contact information.
A retrospective study of cardiovascular disease in captive orangutans (Pongo sp.): This study, conducted by Drs. Amanda Marino and Lauren Howard, will provide a systematic review of the current cases of cardiovascular disease diagnosed in captive orangutans pre-mortem. This project will provide an overview of the unique attributes of orangutan physiology and how it may affect cardiac function, as well as how heart disease in orangutans differs from other great apes. Additionally, this paper will act as a source of information on the clinical signs of disease, risk factors of disease, and the current thoughts on how to manage cardiac disease in orangutans. This paper will advance our knowledge of cardiovascular disease and improve our ability to diagnose and treat captive orangutans. Please click here for project details, information on participation, and contact information.
The Giant Panda Management as a Model for the Malayan Tiger and Bornean Orang Utan Management in Malaysia: Rohana Jani, PhD (University of Malaya), Noor Hashida Hashim, PhD (University of Malaya), Mohd. Tajuddin Abdullah, PhD (University Malaysia Terengganu) and Dennis Ten Choon Yung (University of Malaya/PERHILITAN). The Giant Panda has been placed under the Endangered red list status since 1990.Its status has been down listed from Endangered to Vulnerable in 2016. The conservation works on the Giant Panda is indeed a successful conservation effort. While both IUCN Red List of Threatened Species status for the Malayan Tiger and Bornean Orang Utan have been elevated from Endangered to Critically Endangered in 2015 and 2014. Currently, the Giant Panda conservation model is proven as the successful wildlife conservation model; an in-depth adaption is needed to enable such model to be applied to other threatened species to ensure the model benefited to the targeted species. We seek to understand the Giant Panda conservation management and the possibility that the captive Giant Panda conservation management model may contribute to the conservation management of Malayan Tiger and Bornean Orang Utan. The survey exercise will be distributed to animal captive facilities. The outcome of the study is potentially contributed to the country zoo management and captive wildlife management.
A survey of the prevalence and perceived efficacy of biofloors in great ape exhibits within AZA zoos: Jill Moyse, Curator of Primates, Lincoln Park Zoo. This research project will survey AZA institutions that house great apes to investigate the type of biofloor, if any, the animals have access to throughout the day and overnight. The survey will look at the prevalence of bio floors and the decisions made to provide bio floors from a management perspective. By comparing the attitudes and experiences of institutions that have biofloors to those that do not, we hope to elucidate what the motivations are for institutions to install them as well as what the barriers are to including biofloors in the design of new buildings or the refurbishment of existing exhibits. It is expected that cost and concerns over hygiene will represent common barriers, but we also anticipate that responses from intuitions that have biofloors in their exhibit will dispel such concerns.
A search for chemical signals in orang-utans: Male orangutan cheek pads are frequently hypothesised to have arisen through sexual selection, influenced by female preference or by male-male competition. However, their potential role in attracting females is not yet fully understood – nor is their potential role in suppressing development in unflanged males. In this preliminary study, Dr Graham L Banes, Professor Tom E Goodwin (Hendrix College) and Melanie Bond (National Zoo, retired) are using use solid phase dynamic extraction (SPDE) gas chromatography mass spectrometry (GC-MS) to identify volatile organic compounds that may emanate from orang-utan cheek pads. The research was featured on the PBS documentary, “Sex in the Wild: Orangutans”.
Variation in Vocal Repertoires of Wild and Captive Orangutans: Although most research on great ape vocalizations has been on chimpanzees, recent field research has produced a catalogue of a wide variety of orangutan vocalizations. Geographic variation in orangutan vocalizations has been identified both within call type and in the presence of certain vocalizations among wild populations. This study aims to catalogue vocal recordings collected across AZA zoo-housed orangutan collections and compare these to those previously documented in the wild. We are especially interested in the context of vocalizations, in novel vocalizations, and in the extent to which keepers can identify the meaning of the vocalizations they hear and record. Please click here for project description and information on participation; click here for contact information.
Respiratory Disease in the North American Captive Orangutan Population: Megan K. Fox of the Los Angeles Zoo and Botanical Gardens and Graduate Student, Evolutionary Anthropology at California State University, Fullerton. This project aims to identify some of the factors that influence the presence of respiratory disease in the North American captive orangutan population. Understanding if there are species differences in the prevalence of disease between the Sumatran and Bornean orangutan, between the sexes, between certain age classes, and between individuals at various developmental stages will provide valuable information and assist in the management of these species. This project also aims to identify other factors that may influence the onset of disease, such as weight, body condition, family history, rearing history, stress events, and environmental factors. Additionally, this project will provide information on the types of symptoms most commonly experienced that will also contribute to the possible early treatment and diagnoses of respiratory disease in captive orangutans. Identifying the risk factors involved will greatly enhance the ability for zoological institutions to act preemptively to treat disease which can ultimately assist in the overall care, management, and survivability of the individuals involved and hence the population as a whole. Contact Megan Fox here.
Insulin Resistance in Old World Primates: Dr. Elena Less of the Cleveland Metroparks Zoo is studying biomarkers of insulin resistance over time in several primate species, orangutans being the representative for apes. Dr. Less’s goal is to determine the effect of increasing age/time spent in captivity on insulin, glucose, cholesterol and triglycerides in banked serum samples from orangutans, Hamadryas baboons, mandrills, ring-tailed lemurs, and red ruffed lemurs. Click here for project description and information on participation; click here for contact information. PENDING ANALYSIS
Important Diseases of Rehabilitant Orangutans: Clinical Aspects of Epidemiology, Diagnosis and Treatment: The Central Kalimantan Orangutan Reintroduction Project of the Borneo Orangutan Survival Foundation at Nyaru Menteng (BOS-NM) holds the largest population of captive orangutans in the world, and associated health and veterinary records over a number of years. Analysis of the data contained within the clinic records, along with some investigative procedures, could fill in a number of knowledge-gaps, and contribute to the health and welfare of captive orangutans not only within BOS-NM, but across the world. Rosalie Dench is working to summarize retrospectively the incidence of orangutan diseases at BOS-NM and establish normal reference ranges for body weight and blood results for the population, which can act as a baseline for analyses, as well as evaluate current diagnostic methods in more detail for several diseases of significance. Click here for more detail on this project; click here for contact information. Work on TB testing, Air Sacculitis Risk Factors and normal ranges for orangutan bodyweight and haematology parameters has already been completed; please contact Rosalie Dench for further information.
Thyroid histology in orangutans with non‐congenital thyroid dysfunction, led by Dr. Sandra M. McLachlan of Cedars‐Sinai Medical Center in Los Angeles. This project investigated thyroid dysfunction in great apes by examining thyroid hormone levels and TSH in all nonhuman great ape genera including adults, adolescents, and infants, and establishing a thyroid hormone and TSH database in orangutans, gorillas, chimpanzees, and bonobos (447 individuals). The most striking differences found between these 4 great ape genera were greatly reduced FT4 and FT3 levels in orangutans and gorillas, and elevated TSH levels in gorillas, compared with chimpanzees and bonobos. In addition, autoantibodies to Tg and TPO were detectable in only 2.6% of adult great apes, significantly lower than the approximately 10% in humans. No great apes with thyroid autoantibodies exhibited thyroid dysfunction and neither thyroid autoantibodies nor thyroid lymphocytic infiltration were present in hypothyroid great apes. The researchers also concluded that hypothyroidism in the closest surviving human relatives may involve dietary components including goitrogens but is unrelated to thyroid autoimmunity. Click here to read the Endocrinology article detailing this work.
Cataloging Blood Types for SSP Populations of Great Apes, led by Kathryn Gamble and Jill Moyse, Lincoln Park Zoo. In humans and domestic mammals, blood typing plays an important role in providing excellent medical care in critical care situations. It has been repeatedly demonstrated that humans and great apes have conserved identities within the standard blood typing categories of A-B-O and D(Rh factor). Development of simple table-top laboratory techniques to identify these most basic of blood groups in human patients may be applied to similar benefit in the great ape species. Click here to read the Zoo Biology article detailing this work.
Jaw Gape in Primates, William Hylander, Duke Lemur Center. This project is part of a broad-based comparative study on feeding adaptations in anthropoid primates. There may be important morphological differences in terms of jaw mechanics between orangutans from Borneo as compared to those from Sumatra. If these supposed differences prove to be significant, this will indicate important morphological differences in terms of orangutan jaw-muscle architecture. This in turn is likely related to differences in feeding ecology. This project is now complete and data are being prepared for publication; results will be posted here when available.
Factors influencing male orang-utan reproductive success, Dr. Graham L. Banes, Max Planck Institute for Evolutionary Anthropology. Male orang-utans exhibit one of two physical forms: dominant males develop large 'cheek pads' on their faces, while socially subordinate males do not. The purpose of these ornaments has long been poorly understood. Though cheek pads are hypothesised to make dominant males more attractive to females, thus resulting in greater reproductive success, males without them are also known to have fathered offspring in the wild and in zoos — so why develop cheek pads if you can father offspring without them? A team led by Dr Graham L Banes of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, performed paternity testing of orang-utans at Camp Leakey in Tanjung Puting National Park, Indonesia, to see if the dominant male — Kusasi — was more reproductively successful than his rivals. Not only did Kusasi father almost all of the offspring born during his period of dominance, other males typically only achieved conceptions at the beginning and end of Kusasi's reign, when the dominance hierarchy was potentially unstable. The authors concluded that male bimaturism is likely to be an evolutionarily stable strategy, in which non-cheek-padded males simply bide their time until periods of rank instability. The methods for genetic analyses used in this research, which was published in September 2015 in the journal Behavioral Ecology and Sociobiology, were developed using faecal samples from the Los Angeles Zoo and Botanical Gardens, CA, St Paul's Como Zoo and Conservatory, MN, and Henry Vilas Zoo in Madison, WI. The study was featured by The Washington Post, Discovery News and The Daily Mail, and profiled on Serious Science. Preliminary findings were originally presented at the 9th Annual Orangutan SSP Husbandry Workshop at the Los Angeles Zoo and Botanical Gardens in August 2013.
Cytokine Production and Urinary Excretion in the Orangutan: Drs. Lyle Moldawer and Erin Vogel are investigating the hypothesis that a high degree of endotoxin-responsiveness and cytokine production is shared by orangutans and humans. Their study seeks (1) to determine cross-reactivity among orangutan cytokines and human immunoassay reagents, (2) to determine ex vivo cytokine production to bacterial endotoxin by whole blood obtained from orangutans, and (3) to measure hemopexin and other acute phase reactant proteins that bind endotoxin (LBP, BPI) in the plasma of orangutan. Click here for project description and information on participation; click here for contact information.
A retrospective study of cardiovascular disease in captive orangutans (Pongo sp.): This study, conducted by Drs. Amanda Marino and Lauren Howard, will provide a systematic review of the current cases of cardiovascular disease diagnosed in captive orangutans pre-mortem. This project will provide an overview of the unique attributes of orangutan physiology and how it may affect cardiac function, as well as how heart disease in orangutans differs from other great apes. Additionally, this paper will act as a source of information on the clinical signs of disease, risk factors of disease, and the current thoughts on how to manage cardiac disease in orangutans. This paper will advance our knowledge of cardiovascular disease and improve our ability to diagnose and treat captive orangutans. Please click here for project details, information on participation, and contact information.