Publications & Documentary Films
Publications & Documentary Films
Program Output
Our products are:
- Publications in professional scientific journals, articles in popular magazines and newspapers, student dissertations and reports. Publications are organized by topic and year. The full text for many of them can be downloaded for free directly by clicking the [PDF] link. Others are accessible through the DOI
- Documentary films. (Some are available through You-Tube)
- See also; Education, Conservation, Tours and History.
Recent (2018-2023) Publications
[PDF] Dittus WPJ and Baker A. (2023), Maternal care in wild toque macaques (Macaca sinica) involves prolonged lactation and interbirth intervals as adaptations to reduce maternal depletion and infant mortality in harsh environments. American Journal of Primatology 86 (2): e23584. DOI: 10.1002/ajp.23584.
[PDF] Dittus WPJ, Gunathilake KAS, Felder M (2021). Sharing space with monkeys and human tolerance are critical supplements to primate conservation, but not substitutes for protected nature reserves: a long-term view from Sri Lanka, with a reply to Rudran [2021]. Folia Primatologica 92: 332-244. DOI 10.1159/000521572
[PDF] Dittus WPJ. (2020). Shields on electric posts prevent primate deaths: a case study at Polonnaruwa, Sri Lanka. Folia Primatologica 91:643-653. DOI: 10.1159/000510176
[PDF] Dittus WPJ, Gunathilake KAS, Felder M (2019). Assessing public perceptions and solution to human-monkey conflict from 50 years in Sri Lanka. Folia Primatologica 90(2):89-108. DOI: 10.1159/000496025
[PDF] Dittus WPJ (2018). Nearly sixty percent of Sri Lanka’s mammals inhabiting the rainforests face extinction: time is short to conserve these forests and their diverse dependents. The Sri Lanka Forester 39:49-75.
[PDF] Dittus WPJ (2017). The biogeography and ecology of Sri Lankan mammals point to conservation priorities. Ceylon Journal of Science (Special Issue) 46: 33-64. DOI: 10.4038/cjs.v46i5.7453
Publications by Topic:
Conservation & Wildlife Management
[PDF] Dittus WPJ, Gunathilake KAS, Felder M (2021). Sharing space with monkeys and human tolerance are critical supplements to primate conservation, but not substitutes for protected nature reserves: a long-term view from Sri Lanka, with a reply to Rudran [2021]. Folia Primatologica 92: 332-244. DOI 10.1159/000521572
[PDF] Dittus WPJ (2020). Shields on electric posts prevent primate deaths: a case study at Polonnaruwa, Sri Lanka. Folia Primatologica 91: 643-653. DOI: 10.1159/000510176
Dittus WPJ (2020). Semnopithecus priam spp thersites. IUCN RedList 2020. e.T39841A17982835. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T39841A17982835.en.
Dittus WPJ and Nekaris KAI. (2020). Semnopithecus vetulus spp philbricki. The IUCN Red List of Threatened Species 2020. e.T39845A17988332. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T39845A17988332.en
Dittus WPJ and Watson AC. (2020). Macaca sinica. The IUCN Red List of Threatened Species 2020. e.T12560A17951229. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T12560A17951229.en.
Dittus WPJ and Gamage SN (2020) Macaca sinica ssp opithomelas. The IUCN List of Threatened species 2020. https://dx.doi.org/10.2306/IUCN.UK.2020-2.RLTS.T39841A17982836.en
[PDF] Dittus WPJ, Gunathilake KAS, Felder M (2019). Assessing public perceptions and solution to human-monkey conflict from 50 years in Sri Lanka. Folia Primatologica 90(2):89-108. DOI: 10.1159/000496025.
[PDF] Dittus WPJ (2018). Nearly sixty percent of Sri Lanka’s mammals inhabiting the rainforests face extinction: time is short to conserve these forests and their diverse dependents. The Sri Lanka Forester 39:49-75.
[PDF] Dittus WPJ (2017). The biogeography and ecology of Sri Lankan mammals point to conservation priorities. Ceylon Journal of Science (Special Issue) 46: 33-64. DOI: 10.4038/cjs.v46i5.7453.
[PDF] Dittus WPJ (2013). Subspecies of Sri Lankan mammals as units of biodiversity conservation, with special reference to the primates. Ceylon Journal of Science (Bio. Sci.) (Invited lead article) 42(2): 1-27. DOI:10.4038/cjsbs.v42i2.6606 [PDF] (Download Open Access)
[PDF] Dittus, WPJ (2012). An online forum for exchanging ideas for dealing with issues of pest monkeys. Journal of Primatology 1, 1-2. DOI: 10.4172/2167-6801.1000e107
[PDF] Dittus, WPJ (2012). Problems with pest monkeys: myths and solutions. Loris 26:18-23.
Dittus, WPJ (2007). Man Made Menace. Foray, Sunday Pioneer (India). 28 Oct 2007.
Singh Mewa, Malik Iqbal, Wolfgang Dittus, Anindya Sinha, Aniruddha Belsare, Sally Walker, Melinda Wright, Janaki Lenin, Sujoy Chauduri. (2005). Action Plan for the Control of Commensal, Non-Human Primates in Public Places. pp 1-16. Zoo Outreach Organization, Coimbatore, India.
Molur Sanjay, Douglas Brandon-Jones, Wolfgang Dittus, Ardith Eudey, Ajith Kumar, Mewa Singh, M.M. Feeroz, Mukesh Chalise, Padma Priya, Sally Walker (2003). Status of South Asian Primates: Conservation Assessment and Management Plan (C.A.M.P.) Workshop Report, 2003. Zoo Outreach Organization / CBSG-South Asia: Coimbatore, India, 426pp. ISBN: 81-88722-03-0 (Paperback); 81-88722-04
Dittus, W. P. J., Diaz, T and K. S. S. Goonatillake (2001). Primate conservation and the management of people at the Polonnaruwa Nature Sanctuary, Sri Lanka. XVIIIth Congress of the International Primatological Society, Adelaide, Australia, January 7-12, 2001.
Dittus, W. P. J. (1996). Primate Behavior, Ecology and Conservation. Course Notes, Kandy School of Science, Institute of Fundamental Studies. Sri Lanka.
Dittus, W. P. J. and A. BakerDittus. 1995. Behavior in relation to wildlife management: rationale and techniques. In: “The Development of International Principles and Practices of Wildlife Research and Management: Asian and American Approaches”, (S. H. Berwick and V. B. Saharia, Eds.). Oxford University Press: Delhi. Pp. 295-323.
Dittus, W. P. J. 1986a. Population and conservation status of Sri Lankan primates (Abstract). Primate Report 14: 165
Dittus, W. P. J., and R. W. Thorington, Jr. 1981a. Techniques for aging and sexing primates. In: Techniques for the Study of Primate Population Ecology. Subcommitee on Conservation of Natural Primate Populations, National Research Council. National Academy Press: Washington D. C. Pp. 81-127. https://www.nap.edu/catalog/18646/techniques-for-the-study-of-primate-population-ecology
Dittus, W. P. J. 1981c. Determinants of population density and growth. In: Techniques for the Study of Primate Population Ecology. Subcommittee on Conservation of Natural Primate Populations, National Research Council. National Academy Press: Washington, D. C. Pp. 176-196. https://www.nap.edu/catalog/18646/techniques-for-the-study-of-primate-population-ecology
Dittus, W. P. J. 1981b. Primate population analysis. In: Techniques for the Study of Primate Population Ecology, Subcommittee on Conservation of Natural Primate Populations, National Research Council. National Academy Press: Washington, D. C. Pp. 135-175. https://www.nap.edu/catalog/18646/techniques-for-the-study-of-primate-population-ecology
Dittus, W. P. J. 1977a. The socioecological basis for the conservation of the toque monkey (Macaca sinica) of Sri Lanka (Ceylon). In: Primate Conservation, H. S. H. P. Rainier and G. H. Bourne, eds., Academic Press: New York. Pp. 237-265. https://www.elsevier.com/books/primate-conservation/rainer-iii/978-0-12-576150-5
Forest Ecology
Roberts P, Blumenthal SA, Dittus W. Wedage O, Le-Thorp JA. (2017). Stable nitrogen, oxygen, and nitrogen, isotope analysis of plants from a South Asian forest: implications for primatology. American Journal of Primatology 79 (6): e22656. DOI: 10.1002/ajp.22656
[PDF] Dittus, W. P. J. 1985b. The influence of leaf-monkeys on their feeding trees in a cyclone disturbed environment. Biotropica 17: 100-106. DOI: 10.2307/2388501. [PDF]:
[PDF] Dittus, W. P. J. 1985a. The influence of cyclones on the dry evergreen forest of Sri Lanka. Biotropica17: 1-14. DOI: 10.2307/2388371.
[PDF] Dittus, W. P. J. 1977c. The ecology of a semi-evergreen forest community in Sri Lanka. Biotropica 9: 268-286. DOI: 10.2307/2388145
Demography, Population Genetics and Paternity
Dittus, W. P. J., Keane, B. and Melnick, D. J. (2001). The effects of age and rank on the reproductive success of wild male toque macaques ( Macaca sinica) at Polonnaruwa, Sri Lanka, XVIIIth Congress of the International Primatological Society, Adelaide, Australia, January 7-12, 2001.
Keane, B., Dittus, W. P. J. and D. J. Melnick. (1997). Paternity assessment in wild groups of toque macaques Macaca sinica at Polonnaruwa, Sri Lanka using molecular markers. Molecular Ecology 6:267-282. DOI: 10.1046/j.1365-294X.1997.00178.x
Perez-Sweeney, B.M., Sangchantr, S, Morales, J.C., Dittus, W. P. J. and Melnick, D.J. 1996. Matrilineal relationships among social groups of toque macaques as revealed by variation in the mtDNA D-loop region. In: Proceedings of the XVIth Congress of the International Primatological Scociety and XIXth Conference of the American Society of Primatology. University of Wisconsin-Madison, USA.
Hoelzer, G. A., W. P. J. Dittus, M. V. Ashley, and D. M. Melnick (1994). The local distribution of highly divergent mitochondrial DNA haplotypes in toque macaques (Macaca sinica) at Polonnaruwa, Sri Lanka. Molecular Ecology 3:451- 458. DOI: 10.1111/j.1365-294X.1994.tb00123.x
Hoelzer, G. A., Dittus, W. P. J. and Melnick, D. 1992. Female philopatry and the local distribution of mitochondrial DNA haplotypes in the toque macaque. (Abstract). American Zoologist 31:4A
Dittus, W. P. J. 1975b. The dynamics of migration in Macaca sinica, and its relation to male dominance, reproduction and mortality. (Abstract). American Journal of Physical Anthropology 42: 298.
[PDF] Dittus, W. P. J. 1975a. Population dynamics of the Ceylon toque monkey, Macaca sinica. In: Socioecology and Psychology of Primates, R. Tuttle, ed., Mouton Publishers: The Hague. Pp. 125-152.
Dittus, W. P. J. 1973. Reproduction in Macaca sinica. (Abstract). American Zoologist 12: 173.
Behavioral Ecology, Sociobiology & Evolution
Dittus, W. P. J. 2004. Demography: a window to social evolution. In: Macaque Societies: A Model for the Study of Social Organization, Eds, Thierry, B., Singh, M, Kaumanns, W., Cambridge University Press: Cambridge. Pp. 87-116. Link to preview of chapter
Dittus, W. P. J. 1998. Birth sex ratios in toque macaques and other mammals: integrating the effects of maternal condition and competition. Behavioral Ecology and Sociobiology 44: 149-160. DOI: 10.1007/s002650050
Dittus, W. P. J. 1988. Group fission among wild toque macaques (Macaca sinica) as a consequence of female resource competition and environmental stress. (Abstract). International Journal of Primatology 8: 447
[PDF] Dittus, W. P. J. 1988a. Group fission among wild toque macaques as a consequence of female resource competition and environmental stress. Animal Behaviour 36: 1626-1645. DOI: 10.1016/S0003-3472(88)80104-0
Dittus, W. P. J., and A. Baker. 1987d Investment in sons and daughters by female toque macaques (Macaca sinica). (Abstract). International Ethological Congress. XX: 47
Dittus, W. P. J. 1987a. Group fusion among wild toque macaques: an extreme case of inter-group resource competition. Behaviour 100: 247-291. DOI: 10.1163/156853987X00152
Dittus, W. P. J. 1986d. Competition for food and its effects on the energy budgets and fitnesses of primate individuals and groups. (Abstract). International Symposium on Primates, December 26-31, 1986, New Delhi. p 28.
Dittus, W. P. J. 1986b. Group fusion among wild toque macaques: sex differences in its effects on long-term fitness. (Abstract). Primate Report 14: 114
Dittus, W. P. J. 1986a. Sex differences in fitness following a group take- over among Toque macaques: testing models of social evolution. Behavioral Ecology and Sociobiology 19: 257-266. DOI: 10.1007/BF00300640
[PDF] Dittus, W. P. J. 1984b. A study of social evolution: the influence of environment, behavior and kinship on the demography of a population of toque monkeys. National Geographic Society Research Reports16: 171-182.
[PDF] Dittus, W. P. J. 1982c. Population regulation: the effects of severe environmental changes on the demography and behavior of wild toque macaques. (Abstract). International Journal of Primatology 3: 276.
Dittus, W. P. J. 1980b. Primate social evolution as reflected by socio- demographic relationships. (Abstract). Antropologia contemporanea 3: 191-192.
[PDF] Dittus, W. P. J. 1980a. The social regulation of primate populations: a synthesis. In: The Macaques:Studies in Ecology, Behavior and Evolution, D. G. Lindburg, ed., Van Nostrand Reinhold Co.: New York. Pp. 263-286.
[PDF] Dittus, W. P. J. 1979. The evolution of behaviors regulating density and age-specific sex ratios in a primate population. Behaviour 69: 265-302.
[PDF] Dittus, W. P. J. 1977b. The social regulation of population density and age-sex distribution in the toque monkey. Behaviour 63: 281-322.
Physiology
[PDF] Power Michael, Dittus Wolfgang (2017). Vitamin D status in wild toque macaques (Macaca sinica) in Sri Lanka. American Journal of Primatology 79 (6): e22655. DOI 10.1002/ajp.22655
[PDF] Kohta Goto, Kenji Fukuda, Akitsugu Senda, Tadao Saito, Kazumasa Kimura, Kenneth E. Glander, Katie Hinde, Wolfgang Dittus, Lauren A. Milligan, Michael L. Power, Olav T. Oftedal, Tadasu Urashima. (2010). Chemical characterization of oligosaccharides in the milk of six species of New and Old world monkeys. Glycoconjugate Journal, 27 (7-9): 703-715. DOI: 10.1007/s10719-010-9315-0
[PDF] Milligan, Lauren A; Rapoport, Stanley I; Cranfield, Michael R; Dittus, Wolfgang; Glander, Kenneth E; Oftedal, Ovav T; Power, Michael L; Whittier, Chrsitopher A; Bazinet, Richard, P. (2008) Fatty acid composition of wild anthropoid primate milks. Comparative Biochemistry and Physiology, Part B. 149: 74-82. DOI: 10.1016/j.cbpb.2007.08.006
Growth, Development & Epidemiology
[PDF] Dittus, W. P. J. and Gunathilake, K. A. S. (2015). Validating skinfold thickness as a proxy to estimate total body fat in wild toque macaques (Macaca sinica) using the mass of dissected adipose tissue. American Journal of Primatology 77:618-632. DOI: 10.1002/ajp.22385
Dittus, WPJ (2013). Arboreal adaptations of body fat in wild toque macaques (Macaca sinica) and the evolution of adiposity in primates. American Journal of Physical Anthropology 152:333-344. DOI: 10.1002/ajpa.22351
[PDF] Ekanayake DK, Welch RK, Kieft R, Hajduk S. Dittus WPJ. (2007). Transmission dynamics of Cryprosporidium infection in a natural population of non-human primates at Polonnaruwa. American Journal Tropical Medicine and Hygiene 77(5): 818-822. DOI: 10.4269/ajtmh.2007.77.818
[PDF] Ekanayake, D. K., Arulkanthan A., Horadagoda, N. U., Sanjeevani, G. K. M., Kieft, R., Gunatilake, S., and Dittus, W. P. J. (2006). Prevalence of Cryptosporidium and other enteric parasites among wild non-human primates in Polonnaruwa, Sri Lanka. American Journal of Tropical Medicine and Hygiene 74(2): 322-329. DOI: 10.4269/ajtmh.2006.74.322
Ekanayake, D. K., Rajapakse. R. P. V. J., Dubey J. P., and Dittus, W. P. J. (2004). Seroprevalence of Toxoplasma gondii in Wild Toque Macaques ( Macaca sinica) at Polonnaruwa, Sri Lanka. Journal of Parasitology 90(4): 870-871. DOI: 10.1645/GE-291R
Ekanayake, D. K., Rajapakse, R. P. V. J., Dubey, J. P., Dittus, W. P. J. (2003). Seroprevalence of Toxoplasma godii infection in a natural population of toque macaques (Macaca sinica) at Polonnaruwa, Sri Lanka. Proceedings of the Peradeniya University Research Sessions, Sri Lanka. (October 23, 2003), vol 8: 207
Ekanayake, D. K., Horadagoda, N. U., Sanjeevani, G. K. M., Arulkanthan, A., Gunatilake, K. A. S., Dittus, W. P. J. (2003). Hematology of a natural population of toque macaques (Macaca sinica) at Polonnaruwa, Sri Lanka. American Journal of Primatology 61:13-26. DOI: 10.1002/ajp.10105
[PDF] De Silva, A. M., W. P. J. Dittus, P. H. Amerasinghe, and F. P. Amerasinghe (1999). Serologic evidence for an epizootic dengue virus infecting toque macaques (Macaca sinica) at Polonnruwa, Sri Lanka. American Journal of Tropical Medicine and Hygiene 60: 300-306. DOI: 10.4269/ajtmh.1999.60.300
Kohn, L.A.P., Phillips-Conroy, J.E. and Dittus, W. P. J. 1996. Inheritance of dental dimensions in toque macaques (Macaca sinica). In: Proceedings of the XVIth Congress of the International Primatological Scociety and XIXth Conference of the American Society of Primatology. University of Wisconsin-Madison, USA.
Peiris, J. S. M., W. P. J. Dittus, and C. B. Ratnayake (1993). Sereoepidemiology of dengue and other arboviruses in a natural population of toque macaques (Macaca sinica) at Polonnaruwa, Sri Lanka. Journal of Medical Primatology 22:240-245. https://europepmc.org/abstract/med/8230174
Cheverud, J. M., Dittus, W. P. J. and P. Wilson (1992). Primate Population Studies at Polonnaruwa. III. Somatometric growth in a natural population of toque macaques (Macaca sinica). Journal of Human Evolution 23:51-77. DOI: 10.1016/0047-2484(92)90043-9
Cheverud, J. M. and W. P. J. Dittus (1992). Primate Population Studies at Polonnaruwa. II. Heritability of body measurements in a natural population of toque macaques (Macaca sinica). American Journal of Primatology 27:145-156. DOI: 10.1002/ajp.1350270209
Dewit, I., W. P. J. Dittus, J. Vercruysse, E. A. Harris and D. I. Gibson. 1991. Gastro-intestinal helminths in n natural population of Macaca sinica and Presbytis spp. at Polonnaruwa, Sri Lanka. Primates 32:391-395. DOI: 10.1007/BF02382681
Animal Communication
Bayart F and Dittus WPJ (1987). Vocal differences of infant and juvenile toque macaques (Macaca sinica) according to individuality and degree of social separation. International Journal of Primatology 10 (3): 415
Dittus, W. P. J. 1988b. An analysis of toque macaque cohesion calls from an ecological perspective. In: Primate Vocal Communication (D. Todt, P. Goedeking and D. Symmes, Eds.). Springer- Verlag: Berlin. Pp. 32-50. https://link.springer.com/chapter/10.1007/978-3-642-73769-5_3
Dittus, W. P. J. 1984a. Toque macaque food calls: semantic communication concerning food distribution in the environment. Animal Behaviour 32: 470-477. DOI: 10.1016/S0003-3472(84)80283-3
Dittus, W. P. J. 1982b. Macaque food calls: evolution of an altruistic semantic signal. (Abstract). International Journal of Primatology 3: 276.
Dittus, W. P. J. and R. E. Lemon. 1970. Auditory feedback in the singing of cardinals. Ibis 112: 544-548. DOI: 10.1111/j.1474-919X.1970.tb00827.x
Dittus, W. P. J. and R. E. Lemon. 1969. Effects of song tutoring and acoustic isolation on the song repertoires of cardinals. Animal Behaviour 17: 523-533. DOI: 10.1016/0003-3472(69)90157-2
Behavior
Loew, S.S., Fleischer, R.C. and Dittus, W. P. J. 1996. Male care in wild toque macaques. In: Proceedings of the XVIth Congress of the International Primatological Scociety and XIXth Conference of the American Society of Primatology. University of Wisconsin-Madison, USA.
[PDF] Ratnayeke, A. and W. P. J. Dittus. 1989. Observation of a birth among wild toque macaques (Macaca sinica). International Journal of Primatology 10: 235-242. DOI: 10.1007/BF02735202
[PDF] Dittus, W. P. J. and S. M. Ratnayeke. 1989. Individual and social behavioral responses to injury in wild toque macaques (Macaca sinica). International Journal of Primatology 10: 215-234. DOI: 10.1007/BF02735201
Dittus, W. P. J. and Ratnayeke, S. M. 1989. Care for the injured: a benefit of group life in toque macaques. (Abstract). 21st International Ethological Conference, 9-17 Aug. 1989, Utrecht. Pp. 50
Student Projects & Dissertations
Baker, Anne. 1985. Infant- and JuvenileDirected Care Behaviors by Adult Toque Macaques, Macaca sinica. Ph. D. Dissertation. University of Maryland: College Park
Barrette, Marie France. 2001. Assessing personality profiles for toque macaques at Polonnaruwa, Sri Lanka. University of Laval. Quebec, Canada.
Becker, Kerstin. 2008. Assessment of inbreeding avoidance in social groups of toque macaques with non-dispersing males. Diplomarbeit. Universitaet Koeln, Koeln
Caron, Phillipe. 2001. A habitat survey of the Polonnaruwa Nature Sanctuary. University of Laval. Quebec, Canada.
Dela, Jinie. 1999. The Behavior and Ecology of Purple- Faced Langurs (Presbytis senex vetellus) in Home-Garden and Plantation Habitats. Ph. D. Dissertation, University of Peradeniya, Peradeniya, Sri Lanka.
Ekanayake, Dilrukshi. 2001-2007. Epidemiological studies of the primates at Polonnaruwa. University of Peradeniya, Sri Lanka.
Gannegama Arachchi, Vindiya. 1997. The behavior of toque macaques at Polonnaruwa. Open University, Nugegoda, Sri Lanka.
Hennnayake, Janani Geetha Kumari. 1997. The behavior of toque macaques at Polonnruwa. Open University, Nugegoda, Sri Lanka.
Herath, Tharangani (2005). The hematology of toque macaques. University of Peradeniya, Sri Lanka.
Kumarasinghe, Rasika. (in prep). The role of paternity among dispersing males of toque macaques. M. Phil project, University of Peradeniya, Sri Lanka.
Leasor, Hether. 1992. A survey of populations of Purple-faced Langurs (Trachypithecus vetulus vetulusof the Sinharaja Forest Reserve, Sri Lanka. California State University at Fullerton.
Loew, Sabine. 1993. Paternity assessment in toque macaques and patterns of male care. Smithsonian Institution Postdoctoral Fellow.
Perez-Sweeney, Beatiz. 1995. Matrilineal relationships among social groups of toque macaques as revealed by variation in the mtDNA D-loop region. Columbia University, New Yrok.
Petschauer, Anja. 1993. Begegnungen neu formierter Gruppen bei freilebenden Hutaffen (Macaca sinica) in Shri Lanka. Diplomarbeit, Freie University Berlin
Peiman, Dana (1992). A population survey of the Purple-faced langur Trachypithecus vetulus vetulusof the Sinharaja forest in Sri Lanka. Oxford Brookes University.
Prill, Ebehard. 1996. Zur Bedeutung geschlechtsreifer Maennchen fuer soziale Verbaende freilebender Ceylon-Hutaffen (Macaca sinica L.): Ergebnisse eines Vergleiches von One-Male-Gruppen und Multi-Male Gruppen. Diplomarbeit, Freie Universitaet Berlin
Ratnayeke, S. M. 1989. The Behavior of Old and Injured Individuals in Wild Toque Macaque Society. M. Phil. Dissertation. University of Peradeniya, Peradeniya, Sri Lanka.
Ratnayeke, A. P. (in preparation). The Behavioral Relationship Between Grandmothers and Grandoffspring in Wild Toque Macaques, Macaca sinica. M. Phil. Dissertation, University of Peradeniya, Peradeniya, Sri Lanka
Samarasinghe, Nadeeka D. 2004. A study of the diet of the Gray langur, Semnopithecus priamthersites, at Polonnruwa. Open University, Sri Lanka.
Sanjeevani, Madura. 2005-2006. Hematological and epidemiological studies of primates species at Polonnaruwa. University of Peradeniya, Sri Lanka.
Santiapillai, Charles. 1978. A population survey of the wet zone toque macaques in the Uduwattakelle Sanctuary, Kandy. Postdoctoral collaborator, University of Peradeniya.
Tennakoon, Kumudind N. 2004. A study of the diet of the Purple-faced langur, Trachypithecus vetutlus philbricki at Polonnarwua. Open University.
Vollmer, Sabine. 1993. Zum Verhalten der weiblichen Individuen in neu formierten Gruppen bei freilebenden Hutaffen (Macaca sinica) in Shri Lanka. Diplomarbeit, Freie Uninersity Berlin.
Volz, Jennifer. 1999. Charakterisierung polymorpher DNA-Marker zur Pateritaetsbestimmung bei dem Ceylon-Hutaffen (Macaca sinica). Diplomarbeit, Humboldt Universitaet zu Berlin.
Wijemanne, Bandula. 2007. A study of the slender loris, Loris lydekkerianus at Polonnarwua. Kelaniya University.
Publications by Founding Scientists
The “Primate Project” was initiated in 1965 through the Smithsonian Institution Biological Program in Ceylon (see History) and involved professional biologists (John Eisenberg, Suzanne Ripley, Gilbert Manley, Annette and Marcel Hladik, Ted Grand, Jean-Jacques Petter) and students (Rassanayagan Rudran, Brian van Cuylenberg, Prashanta Amerasinghe, Nancy Muckenhirn and Wolfgang Dittus). Several publications and dissertations emanated from these beginnings.
Amerasinghe FP, van Cuylenberg BWB, Hladik CM (1971) Comparative histology of the alimentary tract of Ceylon primates in correlation with the diet. Ceylon Journal of Science (Biol. Sci) 9:75-87
Dittus, WPJ (1974) The ecology and behavior of the Ceylon toque monkey, Macaca sinica. ). University of Maryland, College Park, (Behavior-Ecology). Ph.D. Dissertation
[PDF] Eisenberg JF, Muckenhirn NA, Rudran R (1972). The relation between ecology and social structure in primates. Science 176:863-874
Grand, T. (1977) Body weight: its relation to tissue composition, segment distribution and motor function. I. Interspecific comparisons. American Journal of Physical Anthropology 47:211-240.
Hladik C, Hladik A (1972) Disponsibilites alimentaires et domains vitaux des primates a Ceylan. Terre et la Vie 26:149-215
Hladik C (1977) A comparative study of the feeding strategies of two sympatric species of leaf monkeys: Presbytis senex and Presbytis entellus. In: Primate Ecology : Studies of Feeding and Ranging Behavior in Lemurs Monkeys and Apes. Clutton-Brock TH (ed) Academic Press: New York, pp 323-353
Manley GH (1978) “Wanderers” in Presbytis senex. In: Recent Advances in Primatology, Vol 1, Behavior, Chivers DJ and Herberet J (eds). Cambridge University Press, New York, pp 193-195
Manley GH (1986). Through the territorial barrier: Harem accretion in Presbytis senex. In: Primate Ontogeny, Cognition and Social Behavior, Else JG and Lee PC (eds). Cambridge University Press, New York, pp 363-370
Muckenhirn NA (1972) Leaf-eaters and their predators in Ceylon: ecological roles of gray langurs, Presbytis entellus, and leopards. Ph. D. dissertation, University of Maryland, College Park
Muckenhirn NA, Eisenberg JF (1973) Home ranges and predation of the Ceylon leopard. In: Eaton RL (ed) The World’s Cats. Winston Wildlife Safari, Winston Oregon, pp 142-175.
Petter JJ, Hladik CM (1970). Observations sur le domaine viteaux et la density de population de Loris tardigradus dans le forts de Ceylan. Mammalia 3: 394-409.
Ripley S (1965) The ecology and social behavior of the Ceylon Grey langur, Presbytis entellus theristes. Ph. D. Dissert. University of California, Berkeley
Ripley S (1967a) The leaping of langurs: problem in the study of locomotor adaptation. American Journal of Physical Anthropology 26:149-170
Ripley S (1967b) Intergroup encounters among Ceylon grey langurs (Presbytis entellus). In: Social Communication Among Primates. Altmann S (ed), University of Chicago Press:Chicago.
Ripley S (1970) Leaves and leaf-monkeys: The social organization of foraging in grey langurs Presbytis entellus theristes. In: Old World Monkeys, Napier JR, Napier PH (eds). Academic Press, New York, pp 481-509
Rudran dissertation, University of Colombo.
Rudran R (1973) Adult male replacement in one-male troops of purple-faced langurs (Presbytis senex senex) and its effect on population structure. Folia Primatologica 19:166-192
Rudran R. (1973) The reproductive cycles of two subspecies of purple-faced langurs (Presbytis senex senex) with relation to environmental factors. Folia Primatologica 19:41-60
Most Recent Film Productions:
2017-2020. Animal Babies: First Year in the Life of a Toque Macaque. BBC Natural World. https://www.bbc.co.uk/programmes/articles/QgKp6ksLWP9y7nq6q0NxZd/meet-the-scientists and https://www.bbc.co.uk/programmes/p07j7329
2019 (April). A Life Among Monkeys. Smithsonian Channel (USA). https://www.terramater.at/productions/a-life-among-monkeys/
2019. One male and his harem of Sri Lankan toque macaques face survival challenges. NHK , Japan (Kenta Takahashi, producer). Broadcast 2020.
2019 (March). Born to Explore with Richard Wiese #213: Sri Lanka Land of Wonder. US Public Television. https://nhpbs.org/schedule/summary.aspx?progId=BorntoExplorewithRichardWiese213
2018 (November). Ein Leben unter den Affen (in German). Alma Mater (Austria).
2018 -2019. Monkey Island – The Secret Life of Monkeys. Plimsoll Prod., UK (Beth Brooks, producer).
2018-2019. Monkey Island – A Mother’s Tale. Natural History, Plimsoll Prod., UK (Claire Clements, producer).https://www.smithsonianchannel.com/shows/monkey-island/a-mothers-tale/1005772/3470246
2018-2019. Monkey Island – Leaving Home. Natural History, Plimsoll Productions.,UK (Claire Clements, producer). https://www.smithsonianchannel.com/shows/monkey-island/1005772
2018-2019. Monkey Island – Trouble in Primate Paradise. Animal Planet (Plimsoll Prod; Claire Clements, producer).
2015-2016. The Art of Living as Told by Toque Monkeys (Japanese). NHK Japanese Television production.
2015. Challenges of Male Monkeys of Sri Lanka: BBC Earth Production for “Sega Orbi” new format of film projection.
2015-2016 (in production) BBC Earth.
2013-2015. Disney Nature – Monkey Kingdom Behind the Scenes Footage
2015 (April). Disney Nature – Monkey Kingdom. (Feature film for theaters)
2012 (May). Toque Macaques of Sri Lanka on BBC Plant Earth Live. BBC Natural World
2012 (November). Growing up a Toque Macaque. National Geographic Society, 24/7 Live.
2012 (December). Wildest Islands – segment on Primates at Polonnaruwa. Discovery Channel (USA) – Off the Fence Productions.
- Dark Days in Monkey City (14,½ hour episodes), (Discovery Channel, Animal Planet)
Earlier Professional Documentary Films
- Monkeys of Sri Lanka. Wild Kingdom Television Show with Dr. Marlin Perkins.
- 1987. Toque Macaques of Polonnaruwa
- “905” Rupavahini Television Corporation, Sri Lanka
- “Nature Calls”. ITN Youth of Asia Television, Sri Lanka
- Temple Troop, BBC Natural World. Winner of 12 international awards.
- Wild Things – Sri Lanka’s Toque Macaques. USA syndicated Television
- Walk on the Wild Side: Monkey Politics. Discovery International
- 905- The Clean Reserve Project. Rupavahini Corporation, Sri Lanka
- The Forest Group. Rupavahini Corporation, Sri Lanka.
- Monkey Families. Discovery International (Marathon Productions).
- Wild Asia: Between Two Worlds. Discovery International (Natural History New Zealand)
- Life of Mammals: Social Climbers. BBC Natural World, with David Attenborough.
- Michaela’s World, Find the King of Temples. Two Hand Productions, UK. (20 min children’s nature education & entertainment program).
- Year on Earth: Monkeys of Sri Lanka. Bahati Productions in collaboration with Earthwatch Institute
- Guardians of Nature. Films Concept Associes, France
- Clever Monkeys. BBC Natural History World with David Attenborough.