Thursday, December 31, 2009

Does Chimp x Gorilla Hybrid Exist?

Darren Naish at Tetrapod Zoology posted an interesting post about chimp x gorilla hybrid or the koolo-kamba. Do you think such hybrid exists or these individuals just display a range of "genetic variation" previously unknown to science? Check out Darren's post now, The Yaounde Zoo mystery ape and the status of the Kooloo-Kamba.

Wednesday, December 30, 2009

Japanese Macaques Floss Teeth

Earlier this year, I blogged about long-tailed macaques (Macaca fascularis) in Thailand using human hair as dental floss to clean their teeth. This behavior gives us an insight to culture transfer as mothers were observed teaching their infants how to floss repeatedly.

In Kyoto, Japan, a Japanese macaque (Macaca fuscata) name Chonpe was observed flossing her teeth using her own hair. She perfected not one, but three flossing techniques.

Lead author Jean-Baptiste Leca told Discovery News that dental flossing could have been a fortuitous yet "accidental byproduct of grooming." Leca, a post-doctoral fellow at Kyoto University's Primate Research Institute, explained that "Japanese macaques sometimes bite into hair or pull it through their mouths to remove external parasites." The hair might have become stuck in Chonpe's teeth, and as she drew the hairs out, "she may have noticed the presence of food remains attached to them". "The immediate reward of licking the food remains off the hair may have encouraged her to repeat the behavior for the same effect in the future," he added.

Chonpe is a middle ranking female with no children. Her only close kin is her mother and her sibling, therefore diffusion of knowledge is somewhat limited to her only sibling. She was observed flossing her teeth about four years ago and had only recently seen this behavior spread among Chonpe's troop. Chonpe was also observed her rolling small stones in her hand while attempting to remove a spine stuck in her palm, so she might be particular an innovative individual, the researchers added.

Chonpe flossing her teeth. Photo by Jean-Baptiste Lena on Discovery News.

Read about the article from Discovery News, Tidy Monkey Flosses Teeth and The first case of dental flossing by a Japanese macaque (Macaca fuscata): implications for the determinants of behavioral innovation and the constraints on social transmission on the journal Primates.

First Molars And Life History In Living African And Asian Apes

Another interesting paper on teeth, specifically the eruption of the first molar (M1), by Jay Kelley and Gary Schwartz from The Institute of Human Origins, Arizona State University (ASU) Since the emergence of M1 correlates with many life history attributes in extant primates, data from this paper can be used to compare the life history among extant primates and also extinct apes and hominins.

"Knowing the age when the first molar appears in the mouths of most primates allows researchers to predict a host of life history attributes, such as gestation length, age at sexual maturity, birth spacing and overall lifespan," said Schwartz. "Humans are unique among primates because our life histories are so slow and thus our molars emerge relatively late. Given that apes are our closest living relatives, understanding the broader context of when the characteristic slower development of humans evolved is of great interest."

"Like annual growth rings inside trees, the cells that produce teeth (both the enamel and underlying dentine) leave behind a trace of their presence, not as annual markers, but as growth lines that appear every day," said Kelley. By slicing the teeth in half, he and Schwartz were able to examine these incremental growth lines in ape individuals that died as their first molars were just erupting into their mouths. "Because teeth preserve this phenomenal internal chronometer, we were able to count up how many days it took the first molars to form," said Schwartz. "In apes and monkeys, first molars start forming very close to the time of birth. As the first molars were still erupting in our specimens, development was incomplete and the final growth line was laid down on the day those animals died. Therefore, by counting backwards from the final growth line to the day of birth, we determined their age at death and thus the age at which that molar was erupting." Using this novel approach, the two scientists were able to mark the age of the gorilla's first molar emergence at 3.8 years, nearly identical to that of a wild chimpanzee's. The orangutan's age at first molar emergence was surprisingly much later, at 4.6 years, which falls closer to the age of approximately 6 years in modern humans.

Read the article, Molars provide insight into evolution of apes, humans by ASU and Dental development and life history in living African and Asian apes from PNAS.

Monday, December 28, 2009

Natural Selection In Great Apes Favor Those With Teeth That Can Handle Fallback Foods

Great apes (orangutan, gorilla and chimpanzee) depend on their teeth to get them through tough times when food is scarce. Natural selection favor individuals with teeth that can process fallback foods, foods that are harder than the great apes normal diet of fruits. The evolution of the thickness of enamel in great apes reflects the mechanical demand of their diet.

"It makes sense if you think about it," says GWU's Paul Constantino. "When resources are scarce, that's when natural selection is highly active in weeding out the less fit, so animals without the necessary equipment to get through those tough times won't pass on their genes to the next generation."

Read the Science Daily article, Among Apes, Teeth Are Made for the Toughest Times and The Influence of Fallback Foods on Great Ape Tooth Enamel by Constantino et al. (2009).

Thursday, December 24, 2009

Chimps Observed Using Tools To Cut Food Into Smaller Pieces

From BBC News, chimps from the Nimba Mountains of Guinea, Africa were observed using tools to chop up and reduce food into smaller bite-sized pieces.

Kathelijne Koops and William McGrew of the Leverhulme Centre for Human Evolutionary Studies, University of Cambridge (UK) with Tetsuro Matsuzawa from Kyoto University, Inundate (Japan) observed this behavior and published it on Primates. They found that these chimps use tools to process Treculia fruits, a large volley ball-shaped fruit that is hard and fibrous.

Wild chimpanzees (Pan troglodytes) are renowned for their use of tools in activities ranging from foraging to social interactions. Different populations across Africa vary in their tool use repertoires, giving rise to cultural variation. We report a new type of percussive technology in food processing by chimpanzees in the Nimba Mountains, Guinea: Treculia fracturing. Chimpanzees appear to use stone and wooden “cleavers” as tools, as well as stone outcrop “anvils” as substrate to fracture the large and fibrous fruits of Treculia africana, a rare but prized food source. This newly described form of percussive technology is distinctive, as the apparent aim is not to extract an embedded food item, as is the case in nut cracking, baobab smashing, or pestle pounding, but rather to reduce a large food item to manageably sized pieces. Furthermore, these preliminary data provide the first evidence of chimpanzees using two types of percussive technology for the same purpose.

Do chimpanzees (Pan troglodytes) use cleavers and anvils to fracture Treculia africana fruits? Preliminary data on a new form of percussive technology (free abstract).

Wednesday, December 23, 2009

Saturday, December 19, 2009

Global Warming Threatens Folivory Primates

Black and white colobus monkey, one of the folivory species threaten by global warming.

A paper by Korstjens et al. (2009) suggests that even an annual temperature rise of 2°C would threaten folivory primates because these species would be forced to spend more time resting than foraging for food. This paper, Resting time as an ecological constraint on primate biogeography, was published online on Animal Behaviour. Here's the abstract:

Time constraints can limit an animal's potential to survive in a given habitat and the maximum size of its group. Many studies have, therefore, investigated the ecological correlates of time allocated to travelling, foraging and vigilance. However, animals spend more time inactive than active, and understanding the determinants of this resting time may provide new insights into the habitat-specific time-budgeting problems that animals face. We analysed the environmental constraints that determine the minimum amount of daytime an average primate has to spend resting, using data from a wide range of ecologically different species. However, total resting time consists of two components: enforced resting time (imposed on the animal by ecological constraints) and free resting time (the time available for allocation to ecologically functional activities). We show that the ecologically important enforced resting time is determined by diet and annual temperature as well as by temperature variation. Our tests of the biological significance of this relationship show that enforced resting time distinguishes between locations that are suitable or unsuitable for particular genera. We show that an annual temperature increase of 2–4 °C would greatly increase enforced resting time, leading to serious time-budgeting problems for many species. The effect of changes to enforced resting time on the biogeographical distribution of species is especially strong for folivorous primates. This study shows that resting time is an important component of animal behaviour that can help us understand extinction risk and geographical distribution of taxa.

Read more about this paper on, African leaf-eating monkeys are 'likely to be wiped out' by climate change.

Meat May Be The Reason Why Humans Live Longer Than Apes

 Meat, that's what for dinner.

Ever wonder why humans outlive apes? The answer might be because we eat a lot of meat. Genes evolved in humans to adjust to a meat-rich diet helps fight diseases associated with aging such as cancer, heart disease and dementia. Not to mention, the expansion of brain size in the genus Homo is also attributed to an increase in meat diet. Check out the MSNBC article "Meat may be the reason humans outlive apes" and the paper "Evolution of the human lifespan and diseases of aging: Roles of infection, inflammation, and nutrition" by Caleb Finch on PNAS.

Friday, December 18, 2009

Is Eastern Lowland Gorilla A Hybrid Species?

Over at Lawn Chair Anthropology, Zacharoo discusses whether the Eastern Lowland Gorilla (Gorilla beringei graueri) is a hybrid species of the putative "parental" species, the Eastern mountain gorilla (Gorilla beringei beringei) and the Western lowland gorilla (Gorilla gorilla gorilla). Check out the post, here.

Wild Chimps Know What Fire Is ... Kinda.

Jill Pruetz, an ISU associate professor of anthropology, has been studying savanna chimpanzees at her Fongoli research site in Senegal since 2001. Her new study documents how the chimps understand the fire they encounter in the region. Photo by Bob Elbert, ISU News Service.

A new study by Iowa State University anthropologist Jill Pruetz suggests that savanna chimps (Fongoli chimps) in Senegal have a near human understanding of wildfire and would alter their behaviors in anticipation of the wildfire's movement. Along with Thomas LaDuke, an associate professor of biological sciences at East Stroudsburg University in Pennsylvania, they co-authored the paper, which will be published in the American Journal of Physical Anthropology, 2010 edition. (I will post another blog post with link to the paper once it's published).

According to Pruetz and LaDuke, humans must accomplish three cognitive stages to truly control fire. First, they must have a conceptualization of what fire is and understand its behavior. Second, they must have the ability to control fire, including the containment and manipulation of the fire. Third, they must have the ability to start a fire. The Fongoli chimps seem to have mastered the first stage, according to Pruetz. However, she does not anticipate the chimps to start fire anytime soon due to the constrains of their flexibility.

Read the rest of the article from Iowa State University here.

Tuesday, December 15, 2009

Taung Child - Virtual Skull

A partial skull and brain endocast of an Australopithecus africanus child. Photo from Australian Museum.

Through the Australian Museum, you can now access the virtual skull of Taung Child, an Australopithecus africanus. This interactive replica includes the partial skull and brain endocast found in Taung, South Africa in 1924. Raymond Dart published this discovery in 1925.

Click here to look at the interactive Taung Child.

Sunday, December 13, 2009

December 14th is Monkey Day!

For some of you who doesn't know, every year on December 14th (tomorrow) is Monkey Day. Learn more about this holiday on the Monkey Day official website. The folks responsible for Monkey Day is also behind the blog Monkeys In The News. Go check them out and follow them. Do you know what's the difference between a monkey and an ape?

What will you be doing on Monkey Day? Too bad I threw out my Halloween costume ... I was a sad, confused and wet monkey!

Wednesday, December 9, 2009

A New Homo Erectus Endocast From China (Zhoukoudian V)

A newly published paper, A new Homo erectus (Zhoukoudian V) brain endocast from China, by Wu et al. (2009) in Proceedings of The Royal Society B is available online for free. Here's the abstract:

A new Homo erectus endocast, Zhoukoudian (ZKD) V, is assessed by comparing it with ZKD II, ZKD III, ZKD X, ZKD XI, ZKD XII, Hexian, Trinil II, Sambungmacan (Sm) 3, Sangiran 2, Sangiran 17, KNM-ER 3733, KNM-WT 15 000, Kabwe, Liujiang and 31 modern Chinese. The endocast of ZKD V has an estimated endocranial volume of 1140 ml. As the geological age of ZKD V is younger than the other ZKD H. erectus, evolutionary changes in brain morphology are evaluated. The brain size of the ZKD specimens increases slightly over time. Compared with the other ZKD endocasts, ZKD V shows important differences, including broader frontal and occipital lobes, some indication of fuller parietal lobes, and relatively large brain size that reflect significant trends documented in later hominin brain evolution. Bivariate and principal component analyses indicate that geographical variation does not characterize the ZKD, African and other Asian specimens. The ZKD endocasts share some common morphological and morphometric features with other H. erectus endocasts that distinguish them from Homo sapiens.

Tim Jones from has a great write up about the paper, A New Homo erectus (Zhoukoudian V) Brain Endocast From China – Free to Access.

Tuesday, December 8, 2009

Campbell's Monkeys Language Deciphered

A group of researchers from University of St. Andrews, Scotland argues that Campbell's monkeys (Cercopithecus campbelli campbelli) have a primitive form of syntax after spending months of recording their calls as they response to both natural and artificial stimuli. Lead by Dr. Klaus Zuberbühle, the team found that male's alarm calls are made up of an acoustically variable stem, followed by an acoustically invariable suffix. These calls translate to either a specific alarm call or a non-specific alarm call, depending on the syntax.

I'm not an expert in language and linguistics but these findings are interesting in the development of language and speech in primates. Is there a reason why these monkeys are capable of understanding syntax while apes (such as gorillas and chimpanzees) don't?

Read the New York Times article here.
Campbell's Monkeys Use Affixation to Alter Call Meaning by Ouattara et al., (2009)

Monday, December 7, 2009

This Week In Primatology

While I was away at the AAA meeting in Philadelphia, my inbox was flooded with articles on primates from behavioral to molecular level. Here's whats happening this week in primatology:

Primate study halted by US university: Administrators at Oklahoma State University (OSU) in Stillwater have abruptly cancelled an anthrax vaccine study that would have killed dozens of baboons. Can I tell you how happy I am about this? No animals should suffer for science, not even to find a vaccine for humans.

Did Social Climbing Give Us Bigger Brain? by Urban Ethology. It takes a big brain to scheme and plan, so maybe we can thank Machiavellian Intelligence and our complex social system for that big brain of ours.

Monkeys Recognize Their Pals In Photos.Tufted capuchin monkeys (Cebus apella) were tested to see if they have facial recognition using photographs. Pokorny and de Waal (2009) published their findings in the online early edition of Proceedings of the National Academy of Sciences (PNAS). Monkeys recognize the faces of group mates in photographs (free abstract).

Social Conformity Not Unique To Humans. Another study on capuchin monkeys (talk about conforming, LOL). Dr. Marietta Dindo and Professor Andrew Whiten of the University of St Andrews show that capuchin monkeys would copy behaviors of other individuals. Not only do they copy other individual's behavior, they would copy behaviors that are the most popular in the group.

Why Some Monkeys Don't Get AIDS. Yea, why? It's not fair! Two studies reveal why some monkeys don't get AIDS and possibly identifying genes that are related to the progression or resistance to AIDS. Nonpathogenic SIV infection of African green monkeys induces a strong but rapidly controlled type I IFN response (Jacquelin et al., 2009) and Global genomic analysis reveals rapid control of a robust innate response in SIV-infected sooty mangabeys (Bosinger et al., 2009). Both are free access articles in pdf.

And finally, Scent Signals Stop Incest In Lemurs. Chemical identifiers secreted from genital glands by both males and females ring-tailed lemurs (Lemur catta) allow them to avoid incest and engage in nepotism. Decoding an olfactory mechanism of kin recognition and inbreeding avoidance in a primate (Boulet et al., 2009).

Sunday, December 6, 2009

AAA's Student (Or Lack Thereof) Saturday

I was planning on tweeting about Student Saturday yesterday but I've decided against it, not because I was lazy, but I was generally underwhelmed by it. Fully acknowledging that this is the first Student Saturday organized by AAA, I still think that they should have planned a session where all the students can mingle (with a cash bar of course). For a first timer like me, it seems that the convention has too much going on at one time but I soon realized I should have dropped by the day before to pick up the itinerary and plan my day. By the time I walked in to the convention, I had missed both sessions (one about how to sell yourself with your CV and one about getting published) that actually made me want to go to Student Saturday. Bummer!

The graduate school fair was lack luster but this is also due to the fact that my interest lies in primatology, not the other "prominent" anthropology fields that AAA seems to represent. Most of the graduate schools that are present did not have any primatology program or their primatologists are not at the convention. But still, an opportunity to network is still an opportunity to network. Next to the graduate school fair was the book fair, which was more exciting for me to peruse. Surprisingly enough, I manage to find a book about Bigfoot! I also met a nice older lady who was wo-manning the "Gerontology" table (sorry I forgot your name!). We strike up a conversation about gerontology in primates and I told her about the newly published paper by Nakamichi, et al. (2009), which I also blogged last week. I realized that of all the people I spoke with at the convention, she was the only person I had an interesting conversation with.

All in all, Student Saturday was just another day at the AAA convention where they let us, lowly students, pay a small fee to join the festivities and mingle with the anthropological gods. I wish that they had planned sessions specifically for students or at least a reception or a meet-and-greet. Although to their credits, the itinerary does indicate sessions that might be interesting for students. But seriously, where are all the students? Maybe it's just that this is our first time at the convention and once we get a flow of it, things will be much more interesting. Maybe.

Saturday, December 5, 2009

Philadelphia's Baby Sumatran Orangutan Gets A Name!

After two months of being born, the female baby Sumatran orangutan from Philadelphia Zoo finally gets a name! The baby is given the name Batu, named after a group of islands of the coast of Sumatra. The other two choices were Kadoa (small gift) and Anoano (blessing). Over half of the 3.400 online votes favor the name Batu, myself included. Batu was born in October 2nd, 2009 to father Sugi and mother Tua.

Batu, in the embrace of her mother Tua. Photo from Philadelphia Inquirer.

According to the Philadelphia Inquirer:
"PECO is sponsoring an Orangutan Baby Naming Weekend from 11 a.m. and 3 p.m. tomorrow and Sunday which will include special activities at the PECO Primate Reserve and giveaways to first 200 people to arrive at the zoo each day."
 So, go on down to Philadelphia Zoo and celebrate the merriment! Unfortunately I'll be at the American Anthropological Association (AAA)'s Student Saturday today and will be going to Mutter Museum with my friends on Sunday (though I might be able to persuade them to go to the zoo instead).

Read more about Batu: Baby Sumatran Orangutan Born In Philadelphia Zoo & Name The Female Baby Sumatran Orangutan.

Thursday, December 3, 2009

American Anthropological Association (AAA): Student Saturday and Nonja, The Orangutan

Packing and getting ready for AAA's Student Saturday in Philadelphia this Saturday. Will blog about the event so stay tune!

Nonja and her camera.

In the mean time, I'm gonna leave you with Nonja, a female orangutan from Schönbrunn Zoo, Vienna. Nonja made headlines and became a sensation on Facebook for using a camera to take photo of herself and her enclosure. She probably doesn't know what a camera is but she knows that every snap of the camera dispenses a raisin as a treat. So you can say she's camera happy because she's raisin happy.

Nonja and her Facebook pose.

This is the "info" on Nonja's Facebook profile, in German.

"Nonja ist ein 33-jähriges Orang-Utan Weibchen. Die Fotos auf dieser Website sind von ihr fotografiert und zeigen das neue Gehege mit 750qm Freianlage im Tiergarten Schönbrunn. Die passende Kamera wurde von der Firma Samsung zur Verfügung gestellt."

"Nonja is a 33-year-old female orangutan. The photos on this website are photographs taken by her and shows the new enclosure with 750qm open area in the Schönbrunn Zoo. The camera was provided by the company Samsung."

Read the full story from Reuters here. Also, check out Nonja's Facebook profile!

Tuesday, December 1, 2009

Humans Were Born With The Urge To Help

The New York Times Science section has an interesting article about humans and their proneness to help each other, "We May Be Born With an Urge to Help".

Their [biologists] conclusions are derived in part from testing very young children, and partly from comparing human children with those of chimpanzees, hoping that the differences will point to what is distinctively human. The somewhat surprising answer at which some biologists have arrived is that babies are innately sociable and helpful to others. Of course every animal must to some extent be selfish to survive. But the biologists also see in humans a natural willingness to help ... “That’s why we have moral dilemmas,” Dr. Tomasello said, “because we are both selfish and altruistic at the same time.”

Read more about the news article, here.