Orangutan at Sepilok (Photo: Kristin Abt)

A recent article “Fostering Appropriate Behavior in Rehabilitant Orangutans (Pongo pygmaeus)” published online in the International Journal of Primatology discusses research on the behavior of rehabilitant orangutans (Pongo pygmaeus and P. abelii) at the Orangutan Care and Quarantine Centre in Pangkalan Bun, Kalimantan (Indonesian Borneo). Much past research has focused on postrelease behavior of rehabilitated orangutans and on the behavior of wild individuals; therefore, this research is especially timely and useful for the number of centers currently attempting to rehabilitate the ever-increasing number of displaced great apes and other fauna (Descovich et al., 2011).

Orangutans (n=40) in this study included males and females, mass classes ranging from 5 to 25 kg, and good, moderate, and poor health distinctions. Individuals were observed continuously for a period of 5 hours during 3 separate forest excursions each.  A number of behaviors relevant to postrelease success in the forest habitat were recorded (type of locomotion, social behavior, such as play, human caretaker interaction, point of height in tree or on ground, feeding and food choice, grooming, etc.).

Results from this study showed that rehabilitant individuals’ masses were associated with the amount of time spent at the centre. Authors note this finding as a result of the early age of admittance to the centre for most individuals. Further, orangutans in better health spent an increased amount of time consuming food and less time resting than other categories. In terms of locomotion (>30% of overall time), quadrupedal movement in trees was the dominant method (again, with orangutans in better health doing so more often). Individuals who had been at the Care Centre longer spent more time on the ground rather than swinging or other locomotion. As the day in which focal individuals were observed continued, human interaction increased.

As rehabilitation of orphaned individuals is a component of the long-term species survival of orangutans, research regarding the behavior of these individuals is important for increasing the chance of postrelease survival and success. Additionally, as their habitat is lost as a result of a number of conservation threats, land protection is necessary to provide habitat in which the released individuals and their wild conspecifics can live.

Reference

Descovich, K. A., Galdikas, B. M., Tribe, A., Lisle, A., & Phillips, C. J. 2011. Fostering appropriate behavior in rehabilitant orangutans (Pongo pygmaeus). International Journal of Primatology. doi:10.1007/s10764-011-9491-1

Orangutan Foundation International (a 501(c)3 nonprofit organization) supports the work of the Orangutan Care and Quarantine Centre and other crucial efforts to promote orangutan conservation, including land protection, research, and education. Visit www.orangutan.org to donate directly to OFI. If you would like to donate items specifically to enhance the lives of individuals at the Care Centre, visit this wishlist to select items that orangutans, such as those in this study, will greatly benefit from. If you would like to learn more, look for the upcoming IMAX© movie Born to Be Wild to be released in theaters April 8, 2011.

One remarkable finding of the study is the estimated divergence between the Sumatran and Bornean species. The team calculated the two species diverged 400,000 years ago. We know that land bridge between Indonesia’s Sumatra and Borneo split at least 21,000 years ago but until now we’ve never known at what time the two speciated.

Compared to the two other great apes whose genomes have been sequenced, humans and chimps, the orangutan genome has changed much less. We’re still waiting on the gorilla genome to be finished. Oangutans originated some 12 million to 16 million years ago. Theoretically, orangutans have had more time to accumulate  genetic variation compared to humans and chimpanzees, which split into their own lineages 5 million to 6 million years ago. One would expect at least twice as much variation in the orangutan genome. However, in the study, a comparison of the three genomes shows that humans and chimpanzees have lost or gained new genes at twice the rate of orangutans.

Why’s that?

The paper explains that orangutan genomes have much fewer active retrotransposons than human and chimp genomes. Retrotransposons, or Alu elements, are essentially jumping genes, that replicate, and amplify then insert into different parts of the genome. The initial 2001 draft of the human genome reported that around 42% of the human genome is made up of retrotransposons. The authors of the orangutan paper illustrate that the human genome has ~5,000 Alu elements, whereas the orangutan genome has 250. This is significantly different. The authors write,

“Reduced Alu retroposition potentially limited the effect of a wide variety of repeat-driven mutational mechanisms in the orang-utan lineage that played a major role in restructuring other primate genomes.”

Personally, and this is my thinking here nothing the authors say — a common source of many human retrotransposons are to prehistoric viruses that integrated into our ancestral DNA. Viruses are communicable. Orangutans are the most solitary Great apes. I suspect they would have much less exposure to viruses because of their social structure, and thus much less chance of insertion of retrotransposon. Again, this is a hypothesis of mine, and I could be very wrong to think this.

Comparison of Orangutan to Great Ape Alu sequences

One last finding, I want to bring up was published in another paper released by the same team, but in the journal Genome Research. In the paper, “Incomplete lineage sorting patterns among human, chimpanzee and orangutan suggest recent orangutan speciation and widespread selection,” coauthors of the previous study write that there are many similarities to the human and orangutan genome, much more similar than human to chimp, in fact. They suspect that could be because humans split from a common ancestor with chimps, of which both species had the same ancestral orangutan DNA. What remains curious is that humans and chimpanzees have evolved separately for millions of years. In the process, chimps for mysterious reasons lost some orangutan DNA that humans retained.

As often in sciences, many more questions arise from studies like these but I am excited that the age of genomics is shedding more light on our fellow primates!

Locke, D., Hillier, L., Warren, W., Worley, K., Nazareth, L., Muzny, D., Yang, S., Wang, Z., Chinwalla, A., Minx, P., Mitreva, M., Cook, L., Delehaunty, K., Fronick, C., Schmidt, H., Fulton, L., Fulton, R., Nelson, J., Magrini, V., Pohl, C., Graves, T., Markovic, C., Cree, A., Dinh, H., Hume, J., Kovar, C., Fowler, G., Lunter, G., Meader, S., Heger, A., Ponting, C., Marques-Bonet, T., Alkan, C., Chen, L., Cheng, Z., Kidd, J., Eichler, E., White, S., Searle, S., Vilella, A., Chen, Y., Flicek, P., Ma, J., Raney, B., Suh, B., Burhans, R., Herrero, J., Haussler, D., Faria, R., Fernando, O., Darré, F., Farré, D., Gazave, E., Oliva, M., Navarro, A., Roberto, R., Capozzi, O., Archidiacono, N., Valle, G., Purgato, S., Rocchi, M., Konkel, M., Walker, J., Ullmer, B., Batzer, M., Smit, A., Hubley, R., Casola, C., Schrider, D., Hahn, M., Quesada, V., Puente, X., Ordoñez, G., López-Otín, C., Vinar, T., Brejova, B., Ratan, A., Harris, R., Miller, W., Kosiol, C., Lawson, H., Taliwal, V., Martins, A., Siepel, A., RoyChoudhury, A., Ma, X., Degenhardt, J., Bustamante, C., Gutenkunst, R., Mailund, T., Dutheil, J., Hobolth, A., Schierup, M., Ryder, O., Yoshinaga, Y., de Jong, P., Weinstock, G., Rogers, J., Mardis, E., Gibbs, R., & Wilson, R. (2011). Comparative and demographic analysis of orang-utan genomes Nature, 469 (7331), 529-533 DOI: 10.1038/nature09687

Hobolth, A., Dutheil, J., Hawks, J., Schierup, M., & Mailund, T. (2011). Incomplete lineage sorting patterns among human, chimpanzee and orangutan suggest recent orangutan speciation and widespread selection Genome Research DOI: 10.1101/gr.114751.110

Des Moines, Iowa – January 29, 2009 – Great Ape Trust of Iowa scientist Dr. Serge Wich and three other internationally respected orangutan experts have edited a book set for release in the United States next month that, for the first time, compares data collected at every known orangutan research site and examines the information to discern differences and similarities among orangutan species, subspecies and populations.

Scientists are aware of significant variation in the behavior, morphology and life histories of orangutans, found only on the islands of Sumatra and Borneo, but the comparative approach in Orangutans: Geographic Variation in Behavioral Ecology and Conservation provides a theoretical framework to explain them, according to Wich and his co-editors. The data analyzed in the book, collected for Sumatran orangutans (Pongo abelii) Bornean orangutans (Pongo pygmaeus) and their subspecies, provide a foundation for conservation action plans to save the critically endangered wild orangutans from extinction, and also emphasizes the effects of human settlement on orangutans and their habitat.

Wich and his esteemed co-editors – Dr. S. Suci Utami Atmoko, a biology research associate and lecturer at Universitas Nasional in Jakarta, Indonesia, and a member the IUCN-SSC Primate Specialist Group; Tatang Mitra Setia, who has studied Indonesian primates since 1979 at the Ketambe Research Center and is the dean of the biology faculty at Universitas Nasional; and Dr. Carel P. van Schaik, a Dutch primatologist who is a professor and director of the Anthropological Institute and Museum at the University of Zürich, Switzerland – all have extensive backgrounds tracking and studying wild orangutans. All also are widely respected for their own scientific publications.

For this book, they brought together more than 70 of the world’s leading orangutan experts to rigorously synthesize and compare the data, quantify the similarities and differences, and seek to explain them.

“Instead of just getting really good people with data from one population, we sought data from many scientists,” Wich said. “This gives us the advantage of looking at differences site by site.”

The comparison gives scientists a better understanding of how such ecological factors as fruit availability in the forest, for example, affects various orangutan populations. “By taking a look at differences in ecology, it’s easier to understand variation,” Wich said. “That’s why looking at one taxon is a very useful approach.”

Having such data available in one source “makes us think differently about conservation issues,” he continued. “If all orangutans were all the same, maybe saving a population here and a population there is enough to conserve the species, but if they’re different, conservation measures should reflect that. This site-by-site collection of data makes it much more strategic for us to consider all of these differences. What we are trying to do is not only preserve numbers, but also take geographic variation into account.”

The book points out not only differences between Sumatran and Bornean orangutans, but also their subspecies. There are three known Bornean orangutan subspecies – Pongo pygmaeus pygmaeus, Pongo pygmaeus wurmbii and Pongo pygmaeus morio – and no known subspecies of Sumatran orangutans.

Great Ape Trust’s Dr. Rob Shumaker, one of the scientists invited to contribute chapters to the volume, said the book is “extraordinarily important,” in part because it fills a void in both the quality and quantity of comparative data available on orangutans. “The comparative literature that exists on orangutans is sparse when compared to what we know about chimpanzees, for example,” said Shumaker, who also pointed to a “very notable and unusual level of collaboration among scientists who worked together to create chapters.”

“It’s rare to achieve this level of collaboration and cooperation among field researchers,” he said. “It’s very difficult to find that when looking through literature on other species and other types of great ape.”

Shumaker said that collectively, scientists contributing chapters to the book paint a clearer picture of the flexibility and range of orangutan behavior in the wild and provides important insight to researchers working with captive orangutan populations. Though he has studied the mental abilities of orangutans for more than 20 years, Shumaker said the information presented in the book “revolutionizes my perspective and thinking into the level of variation we might expect in orangutans in captivity.”

Another contributing author, Dr. Anne Russon, said the book is noteworthy not only because it systematically attempts to consider orangutan biology and conservation across the whole of the orangutan’s rage, but also because of the sweeping scope of the research presented.

“It is simply vast,” said Russon, a professor of psychology at Glendon College, York University, Toronto, who since 1989 has studied intelligence and learning in ex-captive Bornean orangutans rehabilitated and released to free forest life.

“It required the work of a huge number of scientists and conservationists, with a very wide range of expertise and covering a time span of more than 30 years, to develop this kind of view of orangutans,” she said. “This effort identified similarities – and perhaps more important, differences – among orangutans that were either unknown or at best only hinted at in the past.”

Though some of the data reported in the book’s chapters remain suggestive because they were not collected to today’s methodological standards, “that points the way forward, in the sense of indicating what aspects of orangutan biology now need attention,” Russon said.

Background Information

Great Ape Trust of Iowa is a scientific research facility in southeast Des Moines dedicated to understanding the origins and future of culture, language, tools and intelligence. When completed, Great Ape Trust will be the largest great ape facility in North America and one of the first worldwide to include all four types of great ape – bonobos, chimpanzees, gorillas and orangutans – for noninvasive interdisciplinary studies of their cognitive and communicative capabilities.

Great Ape Trust is dedicated to providing sanctuary and an honorable life for great apes, studying the intelligence of great apes, advancing conservation of great apes and providing unique educational experiences about great apes. Great Ape Trust of Iowa is a 501(c) 3 not-for-profit organization and is certified by the Association of Zoos and Aquariums (AZA).

“Orangutan population on Indonesia’s Sumatra island dropped almost 14 percent since 2004…. On Borneo island, which is shared by Malaysia, Brunei and Indonesia, have fallen by 10 percent…

The number of orangutans on Sumatra has fallen from 7,500 to 6,600 while the number on Borneo has fallen from 54,000 to around 49,600.”

Despite the active conservation initiatives to help save these apes, the numbers are dropping at alarming rates. Because of that, the orangutan maybe the first extant great ape to go extinct. Much of the problem is due to the aggressive deforestation efforts by palm oil producers, who tear down forests to plant palm trees and make biofuel. This illustration to the right documents the deforrestation of Borneo in the past and projects the impact in the future.

I’ve covered this topic before, and summarized the history Primatology.net’s blogging on orangutan conservation.

• Spread the word, “Choose the right biofuel or the Orang-utan gets it!”
• Palm Oil Industry and the displacement of Orangutans
• Rebuilding forests in an effort to save orangutans in Borneo
• UN Reports that Orangutan Habitat will be gone in 15 years

Specifically the orangutans were using sticks to pry open pulpy fruits that have “Plexiglas needles” capable of delivering a painful jab covering them. Using the tools, the orangutans were getting past handling the prickly husk and into the nutritious fruit. From an anthropological viewpoint, tool use represents an aspect of culture, since the entire group participates in a behavior that has developed over time. One unique thing to clarify is that only Sumatran orangutans have been observed to use tools, not orangutans from Borneo.

Recently, Gerd Schuster co-author of Thinkers of the Jungle: The Orangutan Report, took this photograph of,

“a male orangutan, clinging precariously to overhanging branches, flails the water with a pole, trying desperately to spear a passing fish…

The extraordinary image, a world exclusive, was taken in Borneo on the island of Kaja…

This individual had seen locals fishing with spears on the Gohong River.

Although the method required too much skill for him to master, he was later able to improvise by using the pole to catch fish already trapped in the locals’ fishing lines.”

Pretty awesome image, no? If you wanna read more about orangutan tool use, here are three papers on the topic:

Schaik, C.P., Fox, E.A., Sitompul, A.F. (1996). Manufacture and use of tools in wild Sumatran orangutans. Naturwissenschaften, 83(4), 186-188. DOI: 10.1007/BF01143062

Call, J., Tomasello, M. (1994). The social learning of tool use by orangutans (Pongo pygmaeus). Human Evolution, 9(4), 297-313. DOI: 10.1007/BF02435516

van Schaik, C.P. (2003). Orangutan Cultures and the Evolution of Material Culture. Science, 299(5603), 102-105. DOI: 10.1126/science.1078004

Suffice to say, it is always welcoming to read of a new publication announcing a new Miocene ape. We’ve had the pleasure to do so, with the introduction of Nakalipithecus nakayamai, a Miocene Ape from Kenya. PNAS is carrying the paper now, under the title, “A new Late Miocene great ape from Kenya and its implications for the origins of African great apes and humans.” The paper is written by both Japanese and Kenyan academics.The fossils of N. nakayamai were found over a decade ago in a fossil bed called Nakali, which is about 40 kilometers west of Maralal. These fossils make up the holotype of the species, which is the scientific way of saying this is the type specimen. A total of 11 fossils make up this specimen, including a right mandibular fragment with M1–M3, left I1, right C*, right P3, left P4, right M1, right I2, left P3, right P4, right M, left M, and a left dp.

As you can see, these are all teeth. Teeth are especially important in understanding evolution because they offer more resolution of information than other parts of the skeleton.

The teeth are similar in size to modern orangutans and gorillas, some of the larger great apes. The teeth differ from other known species of apes in having a much different upper canine. I’m not gonna rehash how it’s different because it requires an intimate understanding of tooth anatomy, morphology, and terminology. Just take my word for it, it’s a much different canine, as long as it is broad. Have a look for yourself,

The premolars are also different. They are elongated but have reduced cusps.The authors indicate that N. nakayamai is similar to another genus of Miocene ape, Ouranopithecus. However, the differences from Ouranopithecus are in thinner enamel and less inflated cusps in the molars. The authors compare the fossils to other Miocene apes,

“N. nakayamai is distinguished from Ankarapithecus, Sivapithecus, and Khoratpithecus by its large size… more gracile mandibular body… N. nakayamai is [also] different from Dryopithecus in its large size.”

Other than Samburupithecus kiptalami, there aren’t many mid-Miocene apes from Africa known at this time. There is a relatively larger number of Miocene ape fossils found from Turkey and Greece, which has gotten a lot of people, ahem David Begun, to think that apes made a rendezvous out of Africa and into what is now the Middle East and parts of Europe. With this new genus and species, Nakalipithecus, we now see that at least three diverse species of non-cercopithecoid catarrhines survived through the Middle to Late Miocene in Africa, and that suggests a less likelihood that hominoid primates were absent from Africa and were reintroduced from Eurasian populations.

The fossils were unearthed in volcanic mud flow deposits in the northern Nakali region of Kenya. It has been dutifully dubbed Nakalipithecus nakayamai, the genus assigned after the area it was found in while the species is named after Japanese geologist Katsuhiro Nakayama who died while working on the project. Comparisons of the size of the teeth of N. nakayamai shows that it was comparable to a modern female gorilla and a female orangutan. It also resembles another Miocene ape Ouranopithecus macedoniensis, from Greece but several aspects of the dentition indicate a less specialized diet than Ouranopithecus, and place Nakalipithecus in a genus of its own.

I’ll report more on this when I get my hands on the paper.

• Higher Social Skills Are Distinctly Human, Toddler And Ape Study Reveals – ScienceDaily
• Children outsmart chimps – telegraph.co.uk
• Toddlers outdo chimps at apeing the grown-ups – The Times
• Humans’ Complex Social Skills Due to Larger Brains – National Geographic News
• Higher social skills are distinctly human, toddler and ape study reveals – EurekAlert

You really don’t need to read each one of the news sources, because they all are saying the same thing, human toddlers are more sophisticated in their social learning skills than their closest primate relatives. It is not that Earth shattering of a conclusion, even though the average human toddler brain How did the authors get to this outstanding conclusion?

Well first author, Esther Herrmann of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and colleagues put 106 chimpanzees, 32 orangutans, and 105 young German children through a series of complex tests. The kids were around two-and-a-half years old and had been speaking for at least a year and the other non-human apes had all been made accustomed to humans.

The tests were 16 different puzzles designed to weed out the differences in ability between humans and apes. Some of the puzzles included tracking the position of a reward under a cup, a very famous game that tests observation and concentration, and selecting the cup that the researcher pointed to, involved social skills such as communication. Esther demonstrates the test in the image on your right.

The results found that chimpanzees, orangutans, and human children were all generally equal the physical skills tests. But the human children were better at the social skills tests—scoring around 74 percent correct on the tests compared to scores of 33 percent from both groups of apes. I’ve attached Figure 1, from the paper, below for you to see how ‘significant’ human kids preformed better than chimps and orangutans in the social domain… and to be honest it isn’t that significant.

You ask, “Why isn’t it that significant, Kambiz?” Well, do you see the bars above and below the gray boxes in the graph? Those represent the range of values the authors recorded, and in the social domain the human kids lowest range overlaps with the chimpanzee’s highest range. That kinda indicates that either their testing wasn’t thorough enough, i.e. they needed to increase the sample size or add another test to spread out the difference… OR that there really isn’t much of a significant difference.

But there is one example provided were human kids were way better. This test involved a human adult demonstrating how to retrieve food from a transparent tube by popping it open, and the children were almost always able to copy the action immediately and accurately and get the reward. Both ape species, by contrast, failed to understand what the experimenter had done, and instead tried to bite or tear apart the tube to get at the food.

Esther suggests that these tests document that higher social skills are uniquely human, and that it particularly applies to a concept known as “theory of mind” – essentially being able to see things from another’s point of view,

“Social cognition skills are critical for learning. The children were much better than the apes in understanding nonverbal communications, imitating another’s solution to a problem and understanding the intentions of others.

The current results provide strong support for the cultural intelligence hypothesis, that humans have evolved some specialized socio cognitive skills, beyond those of primates in general, for living and exchanging knowledge in cultural groups. Young human children who have been walking and talking for about a year, but who were still several years away from literacy and formal schooling, performed at basically an equivalent level to chimpanzees on tasks of physical cognition, but far outstripped both chimpanzees and orang-utans on tasks of social cognition.

This was true at both the most general and the most specific level of analysis, for individuals never before exposed to these tests, and across the most comprehensive test battery ever given to multiple primate species.”

As you may know humans have the largest brains of all the primates and there are two main theories as to why humans have evolved larger brains than our other relatives. The first, called the “general intelligence hypothesis” suggests that humans’ bigger brains make us better and faster at all kinds of skills, such as memorizing, learning, and planning ahead. But the second, called the “cultural intelligence hypothesis,” suggest that larger brains have specifically enabled us to develop more complex social skills. Herrmann comments,

“This [study] contradicts the general intelligence hypothesis. We would have expected to see a difference in physical skills as well if the general intelligence hypothesis was right.”

That makes sense, our bigger brains enable us to cope with the complexities of social life… but that graph is still not significant enough for me to write one theory over the other.
Additional and related reading from two of the authors:

• “Apes’ and children’s understanding of cooperative and competitive motives in a communicative situation,” Developmental Science, 2006.

But not all of these initiatives are ecological so great when implemented.

Just last week, I toldya how the palm oil industry is displacing and effectively killing orangutans to the brink of extinction.

Well, it seems like Green Peace, a ecological activist movement, has also gotten word on this issue and is mobilizing a strong and effective campaign to raise awareness and hopefully prevent further deforestation and deaths. I was contacted by Andrew, on behalf of Green Peace to help spread the word.

The following video is something you need to watch and you should blog about, digg, email, etc.:

In his email to me, Andrew wrote:

“I am one of many people trying to get some exposure for this campaign and spread the word about the issues surrounding bio-fuels that people, even your perhaps more informed site visitors, might not know. This is a video I think they and everyone else should at east watch and be aware of the message it contains. Green economics, politics and practices are becoming increasingly complex and tied into business. What people are doing that they think IS green and helping animals might really be making things much worse. Its important for people to know they don’t have to preach, take sides or chain themselves to the nearest shrub! Just be informed and help make others.”

I couldn’t say it any better, Andrew. Biofuels may help the battle against climate change, but they are currently doing more harm than good. If rain forests are cut down to make way to grow ‘green fuels’, it will not only destroy homes for animals like the Orang-utans, this will also be catastrophic for the climate releasing more greenhouse gases from destroying forests than will be saved by using biofuels. (more)

For visitors of this site that are from the UK, you can help the effort by sending a email to your transport minister, Stephen Ladyman, telling him that we need for rigorous controls on biofuels. Otherwise the green dream really will become a nightmare.

So please spread the word, at least by digging or stumbling the video!