Loved to Death: New findings have cast a spotlight on the world's cutest primate. Will that be enough to save it? Bgy Anita Neal Harrison.
A slow loris climbing on a branch in the wild.Photos by Ch’ien C. Lee

“The way sellers catch lorises and keep them, it’s quite brutal,” says Rachel Munds, an MU doctoral student who is rapidly emerging as an internationally recognized loris expert. Sellers use pliers and other crude instruments to rip out the teeth lorises use for their venomous bites, she says. Many die in the squalid conditions of illegal, but out-in-the-open, Asian pet markets. Those that do survive usually receive inadequate social, nutritional and habitat care.“ They have a very short lifespan as pets,” says Munds.

These disturbing truths have gained worldwide attention in the last few months, as more than 300 media outlets have picked up on a study published by Munds and two fellow researchers in the American Journal of Primatology. The study revealed a never-before-identified species of slow loris living on the island of Borneo, while also elevating two subspecies to the species level.

“A new species is always great to find,” Munds says. “Lorises are under threat, so it’s an opportunity to spotlight the fact that they are vulnerable. A lot of the press has been really good about saying these species are threatened, and this is why you don’t want to own this animal. ... Some people don’t even know what a loris is, so just making them aware is an important step.”

Beneficial public awareness notwithstanding, Munds says, the reporting on the discovery did raise some issues of its own, particularly among those unfamiliar with species classifications. First, the name slow loris does not refer to one species but to one genus in the Lorisidae family, which falls under the order of primates. Talking about the “slow loris” is comparable to talking about the “falcon,” a genus covering multiple species of birds.

A close relative of the lemur, all members of the Lorisidae family, or lorisids, are nocturnal and live in trees. Their diet includes tree sap, fruit, eggs, birds, lizards and insects. Their range is from Northeast India to the Philippines.

Another point involves what discovery in this context means. It’s not that Munds and colleagues, while out in the jungles of Borneo, laid eyes on a slow loris species never before seen. Far from it. The team wasn’t even in the jungles for this research. Instead, the researchers analyzed museum specimens of one slow loris species, the Bornean slow loris, and photographs of them in the wild, to determine whether differences within the species required a revised taxonomy.

Making such taxonomic classifications requires researchers to deal with one of science’s most nebulous concepts, the line between species. “It’s fuzzy even with biologists,” Munds says. “It depends on the terms you use. There are a lot of species concepts out there.”

In Munds’ study, species is defined as a group of animals sharing enough DNA so that, upon mating, they produce fertile offspring of both sexes. As it’s not exactly practical to mix all of the slow lorises in Borneo together to see which ones mate and with what results, Munds instead had to look for evidence of physiological and habitat differences in museum specimens and photos.

That analysis, completed last year, resulted in the division of the Bornean slow loris, Nycticebus menagensis, into four species: the original species; two previous subspecies, N. bancanus and N. borneanus; and a new, previously unrecognized species, N. kayan.

“We know there are geographic boundaries that are probably inhibiting their gene flow,” Munds says, explaining the new taxonomy. “But it’s also based on the morphological species concept, which is they look different from each other, and those differences lead us to believe they are probably distinct species.”

Recognizing new primate species is becoming more common as scientists learn what observable characteristics — such as coat patterns, vocal cues, sexual anatomy and genetics — differentiate one species from another. In the published findings introducing the new slow loris species, Munds and her co-authors report that in the past 25 years the number of primate species has more than doubled. Most of the new taxa have come from the recognition of “cryptic species,” a distinct species misclassified because of its resemblance to another.


Graphic: YouTube 'play' buttonMunds first became interested in sorting out cryptic species while an undergraduate at Southern Illinois University in Carbondale. She took an Introduction to Primates course with her then-advisor and now study-co-author, Susan Ford, an anthropology professor. Soon she found herself fascinated with the diversity of nocturnal primates.

“I was really interested in gorillas to begin with,” explains Munds, whose passion for nocturnal primates is evident in the tarsier likeness tattooed on the underside of her left forearm, “but there are so many people who study apes, who study chimps and gorillas, that there’s enough people out there doing that. And then we get to these nocturnal animals, and there are so few people studying them. Yet there’s this huge abundance of species.”

Her mind made up, Munds traveled to Oxford Brookes University in the United Kingdom to pursue a master’s in primate conservation. Her advisor there was primatology professor Anna Nekaris, an MU anthropology alumna. Nekaris had been involved with earlier studies aimed at unraveling the taxonomy of the slow loris genus, and it was she who steered Munds toward the project that resulted in the new species findings.

Nekaris’ major contribution to Munds’ work was providing data from her earlier investigations into which morphological features allow “meaningful discrimination” among slow loris species. Nekaris’ findings focused on the lorises’ “face masks,” including the coloring, size and shape of the dark patches around their eyes.

Steamy forest showing tops of treesFor the slow loris study, Munds, with help from Nekaris and Ford, selected 13 features to analyze. Of these 13, eight showed variation across the sample. Using these eight variables, the researchers ran the numbers that resulted in the division of the Bornean slow loris into four groups. Further analysis revealed how distinctive the groups were, and which of eight facial features were most important in distinguishing between the groups.

Once confident with their groupings, the researchers then used a separate statistical procedure to determine that all eight facial features “reached significance” as variables defining the four groups.

Because they knew it would be important to see where these groupings were distributed, the researchers included only photos and specimens with documentation indicating locations. Using this information, they discovered their four groups were not only separated by significant morphological differences, but were also separated geographically.

The final results were exciting, but not shocking, to the researchers. “Logically, one shouldn’t be surprised because Borneo is a very big island, and Madagascar, also a big island, has lots of different species of lemurs,” Ford explains. “The assumption that there was just one species of loris on Borneo should have been suspect long ago.”

Munds says the importance of the research only really hit her as she and Ford ran through the statistics. At first, Munds had demarcated only three species, but then Ford pointed out that one cluster didn’t seem to work. It was much bigger and geographically more spread out, so Ford suggested re-running the stats to see if there might be four, or even five, species.

“It turned out that four matched really well geographically and statistically became quite significant,” Munds says. “And that’s when it started clicking for me: I’m not just going to have to say, ‘Let’s up-list two species,’ but I’m going to have to name a new species.”

That was a thrill Munds had deserved, Ford says.

“She was the driving force for this research,” Ford says. “We consulted throughout, but she took the lead in moving it forward and collecting the data. She’s really a great young scholar, and it’s been great to watch her grow and mature intellectually.”


Graphic: YouTube 'play' buttonDividing the Bornean slow loris species into four species means Borneo, the third largest island in the world, is supporting more diversity than previously recognized. “This sets us up to ask, What are the implications of having all of this diversity?” Ford says. “There are implications for conservation, and there are implications for evolution on Borneo and for understanding the relationships between organisms on Borneo and on the mainland.”

It is these implications for conservation that have most interested Munds. Suddenly, instead of worrying about one population that covers the whole island of Borneo, conservationists must now worry about four smaller populations with their own territories and ranges.

“If you have one species that can span the whole island, it doesn’t seem to be as threatening if certain parts of that island are suffering from deforestation and other parts aren’t,” Munds says. “You assume that this animal still has a safe habitat. But if you knock that one animal into four species — four species that have their own territory and their own range — now we need to protect this pocket, as well as this pocket, as well as this pocket, as well as that pocket. And it becomes more important to set up an appropriate conservation status.”

While deforestation is the greatest threat facing the four Bornean slow loris species, Munds notes there are other threats as well, including a “booming black market demand” for slow lorises. “They are sold as pets, used as props for tourist photos or dismembered for use in traditional Asian medicines,” she says.

Loris sidways a branch, holding on with its feet, preparing to eat a green bug in its hands.All commercial trade of slow lorises is a violation of an international treaty, the Convention on International Trade in Endangered Species of Wild Fauna and Flora, or CITES. This treaty was drawn up in 1973 to ensure that trade in wild animals and plants does not threaten their survival. In 2007, all species in the slow loris genus were granted a listing in CITES Appendix I — the highest level of CITES protection. Trading any species listed in Appendix I is illegal. But the protection is only as good as its enforcement, and in some Southeast Asian countries this means the protection is hardly any good at all.

Butet Sitohang, the international affairs officer for ProFauna Indonesia, an animal protection organization in Indonesia, says what little law enforcement is done there is a result of pressure from NGOs. “If traders go to court, the [sentences] are too light,” Sitohang says. “Meanwhile, the rings of the illegal wildlife trade develop.”

What the Indonesian government needs, Sitohang adds, are “regular patrols in the natural habitats of slow lorises [to] identify the locations prone to poaching, curb the trade and fully enforce the law.”

Nekaris is a prominent advocate for slow loris conservation. In 2007, she launched the Little Fireface Project, a research group named after the Javanese word for loris. The project’s website,, describes its mission as saving lorises “from extinction through learning more about their ecology and using this information to educate local people and law enforcement officers, leading ultimately to empowerment and empathy whereby people in countries where lorises exist will want to save them for themselves.”

In January 2013, the Little Fireface Project held a workshop in association with the Cikananga Wildlife Centre and TRAFFIC Southeast Asia to discuss the challenges in tackling wildlife trade in Indonesia and to create a slow loris conservation action plan. The “empowerment workshop” drew more than 60 participants from government agencies, national and international universities, NGOs and rescue centers. To lead off the workshop, Nekaris presented an overview of the taxonomy and conservation of slow lorises, which showed how critical a correct taxonomy is for successful conservation.

Sharing how she hopes to use the new species findings in her work to save slow lorises, Nekaris points out that the new Bornean species are “just the tip of the iceberg.”

“There are other taxa, too, that will certainly be described in Sumatra and in Indochina,” Nekaris says. “The scientific community had readily accepted new lemur and galago species but had always been reluctant to accept new loris species, despite enormous diversity. So essentially we just can point out that nocturnal primates are cryptic, and it is not always the obvious features that allow us to tell them apart.”

Munds says her doctoral work will be aimed at using genetics to advance taxonomic understanding of slow lorises. She chose MU in large part so that she could work with geneticist Gregory Blomquist, the assistant professor of anthropology who now serves as her advisor.

“I have a lot of support through Dr. Blomquist and a lot of support in the bio department, where I also work with Dr. Lori Eggert [an MU associate professor of biological sciences who was featured in the Fall/Winter 2011 issue of Illumination],” Munds says. “And I’m from the Midwest, from Illinois, so it’s nice to be in a somewhat-urbanized, but not totally urbanized area.”

For her current research, Munds hopes to spend more time in Borneo. She’s visited the jungles before with Nekaris and experienced the thrill of seeing lorises, blissfully free from tiny cages and digital cameras, at home in the wild. Most, she says, were around 30 feet up in the canopy and less than eager to reveal themselves. “The lowest I saw one was maybe 10 feet above me; sometimes they’re very hard to see. But it’s always exciting when one is in your presence.”

Reader Comments

Students from Borneo (East Kalimantan) wrote on July 23, 2013

We live in Balikpapan, Indonesia on the island of Kalimantan (also known as Borneo). We see these beautiful creatures in the local pet stores. We are starting a program to educate locals and expatriates regarding the plight of these animals.

We found this article today as this is the first day of taking classes online through Mizzou for the online High School. If there is anything we can do here to help with your project, please let us know. You can email us at

Grady, Austin, Kiki, Joel, Guy, and Wendy

Ann Pisani wrote on July 26, 2013

Thank you for this article on Slow Lorises. I hope it will educate people on what is a pet and what is not.

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