Primatology.net

The saying “You can’t judge a book by its cover” can sometimes be applied to primate mating system and social system. Primate social systems sometimes differ from mating systems, as evidenced by reports of field observation (although sometimes first-hand field observations mistakenly report and link primate social systems to mating systems). For example, geladas (Theropithecus gelada) can be observed forming multimale-multifemale social groups (herd) as they graze nonchalantly up in the highlands of Ethiopia but when it comes to mating system, geladas mate in a OMU (one-male unit) where one male mates with multiple females of the unit (Gron, 2008). Primate mating systems can be approached in two different point of views: male coercion or female choice. The latter has been the focus of most primatologists in recent years. The Mating System of the Sichuan Snub-Nosed Monkey (Rhinopithecus roxellana), by Guo et al. (2010) on the current issue (Vol 72:1) of American Journal of Primatology is a paper that examines female choice (female mating strategy) in the mating system of Sichuan snub-nosed monkey (specifically the Qinling subspecies) population in the Qinling Mountains, China. I have the pdf. for the paper if anyone wants to read it.

R. roxellana basic unit consist of a OMU, which consist of one male and about eight females. They are arboreal herbivores; living in temperate, mountainous forests in China (Gron, 2007). Males and females exhibit sexual dimorphism, where males are heavier and bigger than females (Gron, 2007). Qinling Golden snub-nosed monkeys (Rhinopithecus roxellana qinlingensis) are considered a subspecies of Sichuan snub-nosed monkeys or Golden snub-nosed monkeys (Rhinopithecus roxellana) by Wilson and Reeder’s Mammal Species of the World. R. r. qinlingensis can be differentiated from the other subspecies by its brilliant golden pelage.

Thought to be of polygynous mating system (one male-multifemale), most of the Sichuan snub-nosed monkeys from Qinling Mountains population were observed in a polygamous mating system (multimale-multifemale) instead. About 18% of the females from this population were observed copulating with males outside of the unit (extra-unit males), in which the researchers call the “extra-unit mating behavior”. This behavior was observed from field site by the researchers. Paternal DNA done on the population shows that more than 50% of the offspring were sired by extra-unit males. 94.5% of copulation with extra unit males were initiated by females.

Three theories were proposed to explain the evolutionary purpose of extra-unit mating behavior: infanticide avoidance, inbreeding avoidance and gaining access to resources. However, Guo et al. (2010) posit that mating with extra-unit males in R. roxellana qinlingensis is adaptive and were probably due to infanticide avoidance. In five years of continuous study, there were no observation of infanticide or aggressive behavior of resident males towards immature individuals which includes those not sired by the resident males. Inbreeding avoidance is most probably not the reason why females copulate with extra-unit males although the researchers lack data to posit that females gain access to resources if they copulate with extra-unit males.

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Ethnoprimatology is defined as the approach that draws from primate socioecology, ethnoecology/environmental anthropology, and conservation biology. This approach enable us to see the multifaceted interaction between humans and nonhuman primates in a dynamic ecosystem. It seems to be something I would like to do and learn more. What’s a better way to incorporate the fundamentals of cultural anthropology and biological anthropology.

An ethnoprimatology paper by Riley and Priston (2010) on the American Journal of Primatology, Macaques in farms and folklore: exploring the human-nonhuman primate interface in Sulawesi, Indonesia (free abstract) explores the complex interaction between macaques and humans through overlapping resource use and cultural perceptions of macaques. If you do not have access to the paper, I can send you a copy of the pdf.

Macaca tonkeana, one of the endemic macaque species of Sulawesi. Photo from Wikipedia.

There are six species of macaques endemic to the island of Sulawesi. Macaca nigra, Macaca nigrescens, Macaca maura, Macaca tonkeana, Macaca hecki and Macaca ochreata. Despite constant crop raiding by macaques, farmers in Sulawesi show considerable tolerance to this behavior. This tolerance can be explained by a positive reinforcement in the farmer’s local culture, folklore and religion. Two types of farming subsistence exists in Sulawesi: dryland crops and wet-rice agriculture.

Macaca nigra, one of the endemic macaque species of Sulawesi. Photo from Wikipedia.

Most dryland crops farmers are Muslim. They abstain from killing and/or eating these macaques (which Balinese Hindus would have no problem doing) as it is considered haram. In the Lindu highlands, the macaques are considered kin by the To Lindu people. In Buton, certain places in the forest are considered sacred, thus these places are protected by the locals. Macaques and other animals benefits from this protection, making these pockets of forest their refuge.

Originally posted on The Prancing Papio.

The IUCN Red List has a Species of the Day feature that highlights species that are threatened of different taxa. Everyday, a species is showcased along with information about the threats they are facing.

Species of the Day for March 3, 2010 is a primate name Kipunji (Rungwecebus kipunji). Kipunji are endemic to Tanzania and was first discovered in 2003. For more about Kipunji, also read The Kipunji Might Have Interbred Baboons.

If you have a Twitter account, follow them at @SpeciesOfTheDay. For more information, go to the IUCN Red List website, http://www.iucnredlist.org

Originally posted on The Prancing Papio.

Laelaps has an interesting post on friendship in male and female baboons. Check out the post, “You just call out my name…”: Friendships in Male and Female Baboons. Insightful hypotheses explaining the friendship between male and female baboon. Would love to read more papers and data on this.

Originally posted on The Prancing Papio.