July 6, 2009

No Sex Can do The Muriquis Harm

Muriquis feeding and resting. Photo from Primate Info Net.

The muriquis, or woolly spider monkeys live in the rain forest of Brazil. They are considered peaceful individuals but an intra-community lethal attack had left researchers to reconsider how peaceful these monkeys are and why such attack occurred.

The image of peaceful individuals mainly stemmed from the northern population. Leaves are abundant in the northern population, so these muriquis chew on leaves all day and males would patiently queue to mate with females. When food is abundant, animals tend to stay in the same place.

However, in the southern population, fruits tend to be more abundant. Generally, females need more caloric intake compared to males, so females from the southern population disperse from the group to find clumps of fruits unlike the northern population where everyone stays together to eat.

It is in the southern population that a gang of six male muriquis were observed attacking another male from the same group, brutally biting his face, body and genitals. The male died about an hour later.

A change in dietary habit might be the clue to why such assault happened, said lead researcher Mauricio Talebi of the Federal University of São Paulo-Diadema, Brazil. Social bonding also explains why a gang of males attacked another male. Due to lack of readily available mates, males may become frustrated, creating tension and aggression between individuals. Because muriqui males bond for life with male siblings and relatives, this facilitates gang attacks, said Filippo Aureli of Liverpool John Moores University, UK. This assault can be seen as aggression among non-kin males.

For more, read ‘Hippy’ monkey is a killer when starved of sex on NewScientist and Intra-community coalitionary lethal attack of an adult male southern muriqui (Brachyteles arachnoides) on Wiley Interscience.

Originally posted on Prancing Papio.

June 8, 2009

Great Apes LOL Like Human Too

A baby orangutan being tickled. Photo from Discovery News.

We’re not the only species that are capable of laughing according to new study. Great apes are able to laugh like humans too, and they do it frequenty. This finding suggests that the last common ancestor of humans and apes also laughed around 10 to 16 million years ago. The ability to laugh subsequently evolved among apes and human, resulting in distinctive ways of laughing among them.

“Orangutans produce a short laugh series of noisy calls. Gorillas, chimps and bonobos produce longer laugh series and the calls are produced more rapidly” said project leader Marina Davila Ross, a primatologist from University of Portsmouth. With partners Michael Owren and Elke Zimmermann, Davila Ross recorded over 800 recordings of 22 juvenile and infant apes, and also three human babies laughing as they were tickled in their palms, feet, necks and armpits.

Presented in the latest edition of Current Biology, the study shows that human laughter is most similar to that of chimpanzees and bonobos, followed by gorillas and orangutans. Human laughter is least similar to those of siamangs, a lesser ape. “These results coincide with the genetic topology of great apes and humans,” said Davila Ross. She doesn’t rule out if apes or monkeys have a sense of humor but said that “it is difficult to find a method to accurately test it”.

Read the rest of the article from Discovery News: Chimps, Other Apes Laugh Like People.

I wonder what function does laughing serve in primates.

Originally posted on The Prancing Papio.

June 2, 2009

Lluc, Anoiapithecus brevirostris, A New Hominoid Species from Abocador de Can Mata, Spain

Els Hostalets de Pierola, Barcelona, Catalonia, Spain

Els Hostalets de Pierola, Barcelona, Catalonia, Spain

By way of Afarensis is news of a new Middle Miocene hominoid species found from the Abocador de Can Mata site in Spain. It is classified as a great ape with many afropithecid and several kenyapithecine features which I’ll give an overview of in a bit. Furthermore, the specimen, IPS43000, is 11.9 million years old, dated via magnetostratigraphic series and associated fauna from the strata it was recovered in.

The authors have published the paper in the journal PNAS under the title, “A unique Middle Miocene European hominoid and the origins of the great ape and human clade.”

What’s unique about this hominoid, aptly named Lluc or enlightenment in Latin, is that it has a very modern face… In other words it’s got a reduced facial prognathism. The specimen includes a fragmented cranium that with most of the face preserved and the associated mandible. While the muzzle of Lluc is so reduced that only find comparable values within the genus Homo, Lluc’s got an array of primitive features, such as super thick dental enamel and teeth with bulbar cusps. The mandible is also very robust. All of which are characteristics of afropithecids — primitive hominoids from the African Middle Miocene.

Anoiapithecus brevirostris (IPS43000)

Anoiapithecus brevirostris (IPS43000)

But other more derived features, like the forward positioning of the zygomatic bone and a bold mandibular torus along with a a reduction in the maxillary sinus, are shared only with the kenyapithecines. Kenyapithecines are a group of apes that ever dispersed outside the African continent and colonized the Mediterranean region, by about 15 million years ago, and are collectively grouped in the genera Kenyapithecus and Griphopithecus.

Ultimately, you can see how this specimen (IPS43000), Anoiapithecus brevirostris, has a combined a set of features that until now had never been found from the fossil record. The array of features allows us enables to identify two possibilities to be the ancestral form to our family (Kenyapithecus and Griphopithecus). The authors take a leap of faith here arguing that when one takes into account that these two genera cannot be considered members of the family Hominidae yet, because they lack its basic diagnostic features, they find it obvious that the origin of our family is a phenomenon that took place on the Mediterranean region during the time span comprised between their arrival from Africa by about 15 Ma, and about 13 Ma, when we began to find in els Hostalets the first members of our family.

    Moya-Sola, S., Alba, D., Almecija, S., Casanovas-Vilar, I., Kohler, M., De Esteban-Trivigno, S., Robles, J., Galindo, J., & Fortuny, J. (2009). A unique Middle Miocene European hominoid and the origins of the great ape and human clade Proceedings of the National Academy of Sciences DOI: 10.1073/pnas.0811730106

May 30, 2009

New Species Of Giant Lemur Found In Madagascar

P.kelyus maxilla fragment. Photo from LiveScience.

Remains of a new giant lemur species, Palaeopropithecus kelyus, was found in Madagascar. Dominique Gommery, a paleontologist at the National Center for Scientific Research (CNRS) in Paris, France said that the discovery confirms 20 years of speculation on its existence.

So far, there are 3 species of giant lemurs identified in Madagascar, Palaeopropithecus kelyus, Palaeopropithecus ingens and Palaeopropithecus maximus. P. kelyus is the smallest of all three, its estimated weight is about 77 lbs. The largest living lemur in Madagascar is the Indri, which weighs about 22lbs. Judging from the teeth, P. kelyus might have chewed on tough food such as seeds and nuts. Read about the article from LiveScience: New Giant Lemur Species Discovered.

Originally posted on The Prancing Papio.

May 29, 2009

A New Malaria Pathogen Found In Chimpanzees From Gabon

Plasmodium falciparum infecting Red Blood Cells

Plasmodium falciparum infecting Red Blood Cells

Plasmodium falciparum is the protozoan parasite that causes malaria in humans and ultimately the death of 2-3 million people a year. If you didn’t know, malaria is one of the most common infectious diseases and an enormous public health problem. Only one other malaria causing protozoan, a sister species of the P. falciparum parasite, P. reichenowi, was known to cause malaria but infects only chimpanzees. That was until researchers based in Gabon and France began sampling pet chimpanzees.

The team collected blood from 19 wild-borne animals kept as pets by villagers in Gabon, 17 of them being chimps. They found out that infected by a Plasmodium parasite, but sequencing of the parasite’s whole mitochondrial genome showed that it wasn’t P. falciparum nor P. reichenowi. Rather, it was a new species more closely related to P. falciparum. They classified the new species as P. gaboni.

hylogenetic relationships among Plasmodium species (including P. sp_K) and associated host groups.

Phylogenetic relationships among Plasmodium species (including P. sp_K) and associated host groups.

They have published their findings in the open access journal PLoS Genetics, under the title, “A New Malaria Agent in African Hominids.” You maybe asking why this is relevant to primatology? Many are against studies that use primates like chimpanzees because of ethical reasons. In situations like this, chimpanzees already infected with the parasite are useful to sample and study to shed light on the genomic adaptations of P. falciparum to humans and thus help in the discovery of new potential drug targets.

    Ollomo, B., Durand, P., Prugnolle, F., Douzery, E., Arnathau, C., Nkoghe, D., Leroy, E., & Renaud, F. (2009). A New Malaria Agent in African Hominids PLoS Pathogens, 5 (5) DOI: 10.1371/journal.ppat.1000446

May 25, 2009

Orangutans Found Cannibalizing Own Babies

Reported in gorillas and documented in chimpanzees, some apes actually cannibalize their own species. However, there were reports of orangutans cannibalizing their own babies were reported in the same forest area of Indonesia, just one month apart from each other.

This might be the first report of an ape eating its own offspring. “Cannibalism has been documented in chimpanzees and reported in gorillas. Never before has any ape species been seen treating its own offspring as a consumable resource”, said David Dellatore of Oxford Brookes University. Dellatore suspects that the mothers’ stressed upbringing may have triggered their later actions. Read the article from BBC – Earth News “Orangutans cannibalise own babies“.

Originally posted on The Prancing Papio.

April 26, 2009

Human Ancestors Were Not Good Tree Climbers, Said Researcher

A new study by Jeremy DeSilva, anthropologist at Worcester State College in Massachusetts suggests that human ancestors may not have been good tree climbers. He suggests that our ancestors traded in arboreal adaptations to evolve bipedality.

By recording how wild chimpanzees climb tree in Uganda’s Kibale National Park, DeSilva found that chimpanzees flex their ankles 45 degrees from normal resting position while modern humans flex their ankles a maximum of 20 degrees while walking. Flexing any more than that and a modern human’s ankle will suffer serious injuries.

DeSilva then compared the ankle joint, the tibia and the talus, in great apes and fossil hominins between 4.12 million to 1.53 million years old. He found that all of the hominin ankle joints resembled those of modern humans rather than those of apes, suggesting that this joint “form” took on its current configuration early in human evolution.

Read the full ScienceNOW article.

Originally posted on The Prancing Papio.

April 26, 2009

Introducing A New Guest Blogger, Raymond Ho

As you may have noticed, it has been rather silent here for the last 5 months. I’m happy to break the silence with most excellent news of a new guest blogger to Anthropology.net & Primatology.net, Raymond Ho, of The Prancing Papio. I’ve been an avid reader of Raymond’s blog ever since he started it earlier this year. His balance in being thorough, inquisitive, and consistent has kept me subscribed.

For a little background on Raymond, he’s currently an undergraduate Biological Anthropology student at CUNY, Queens College and is expected to graduate next month. As you can tell from the title of his personal blog, he’s passionate about primatology, especially grooming. His senior honors thesis compares grooming between hamadryas baboons and gelada baboons. But he does write on many anthropological topics as well, such as paleoanthropology — one of my favorite topics!

I’d like to extend a warm welcome to Raymond for accepting to blog here. I’m very grateful, actually, especially since I’m still an inactive member of this site and hope that he and others will keep this site ticking in my absence. If you haven’t followed his blog, I suggest you do. He’ll continue posting there and here.

February 24, 2009

Orangutans: Geographic Variation in Behavioral Ecology and Conservation

New volume is the first to offer a site-by-site comparison of data recording similarities, differences in orangutan populations

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.
nr_03b09
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).

November 19, 2008

Introducing Ruben Blijdorp, A New Editor To Primatology.net

As you may have noticed, the last book review posted on Primatology.net the other day, was not authored by me. In fact, it was authored by Ruben Blijdorp, a primatologist from Holland. He contacted me the other week expressing interest in helping out with this site. He has studied under Jan van Hooff and Liesbeth Sterck at Utrecht University and has conducted field work with the orangutans at Gunung Leuser National Park, Indonesia. He’s going to be pursuing his PhD soon and is really passionate about primates.

Ruben is going to act as an editor, contributing posts and upping the scientific context when needed. Since we’ve had many rogue commentors, he’s also going to help me keep the discussion threads on track and commentors well behaved. Usually, I post these sorts of introductions before the new members blogs, but I was flying all yesterday and just only got a chance to sit down and write this. Furthermore, I am very busy lately and often neglect this blog from time to time, so I’m really excited to have his help and look forward to reading what he has to add. I want to send off a warm welcome Ruben to Primatology.net, and hope you all do too!