Primatology.net

Klaus Zuberbühler and team published his report of blue monkey vocalizations in the Royal Society’s journal Biology Letters. The paper is titled, “Male blue monkeys alarm call in response to danger experienced by others.” I don’t have access to the journal, nor am I willing to pay $50 for the privileged to read it. If anyone has access to Biology Letters and is kind enough to send me a copy of the paper, I’d be more than grateful. In lieu of the primary source, I’ll be summarizing what Lauren Cahoon, from ScienceNOW Daily News, reported on it.

Klaus and team observed and recorded the behaviors of male blue monkeys (Cercopithecus mitis stuhlmanni) which live in the Budongo Forest, Uganda. Blue monkeys make two vocalizations. Lauren describes them as,

“predator-specific calls: the “hack,” a low, gagging sound that warns about eagles, and the “pyow,” which sounds a bit like a laser gun and warns about more general dangers on the ground, such as leopards.”

The meanings behind the hack and pyow have been largely interpreted as a basic “watch out” warning call. In this new paper, Klaus and team have shown that the frequency of calls indicate the urgency of the danger. In other words, male blue monkeys yelled more frequently if members of their group were close to a crowned eagle. But, if they were further away from the danger the monkeys would lessen the number of calls. They found this out by playing the

“recordings of hacks and pyows from a loudspeaker near blue monkey troops, which are usually made up of a lead male and about 10 to 40 females and young. The recorded sounds prompted the lead male to follow up with his own alarm call, and he typically repeated the cry about 23 times. However, if a female or baby was close to the loudspeaker–the “predator”–the males gave an average of 42 cries. It didn’t matter how close the male was to the danger; he sounded the red-alert alarm only when the females and young appeared to be at risk.”

This behavior suggest that blue monkey males are concerned of any threat to their group, regardless of the impact it to his own direct well-being. Gregory Radick generally agrees but suggests that its less of a group specific reaction and more of a highten level of fear. Of course that hasn’t come without criticisms, because many don’t believe monkeys to be so selfless. Michael Owren thinks that the males are simply more emotional because they are in the proximity of females.

Two years ago, Klaus Zuberbühler and Kate Arnold reported on this behavior in male putty-nosed monkeys (Cercopithecus nictitans) , a close relative of the blue monkey. Their paper was published in Nature, under the title, “Language evolution: Semantic combinations in primate calls.” Male putty-nosed monkeys also make two distinct vocalizations. The frequency and sequence of these calls was also understood to be a danger specific response.

If you’re curious to listen to what the hacks and pyows of male putty-nosed monkeys sound like, listen to these sound bites:

A series of ‘pyow’ calls: these can function as an alarm in response to a nearby leopard, but are also used in other contexts.

A series of ‘hack’ calls: mostly functions as an alarm in response to a nearby eagle.

A ‘pyow–hack’ sequence: sometimes produced in response to eagles or leopards; normally results in significant movement by the monkey troop in a variety of contexts.

Arnold, K., Zuberbühler, K. (2006). Language evolution: Semantic combinations in primate calls. Nature, 441(7091), 303-303. DOI: 10.1038/441303a

This year marks the 60th anniversary of the founding of primatology in Japan, thanks to the works of Kinji Imanishi. Current Biology hosts an essay by Tetsuro Matsuzawa and William McGrew, which reviews Imanishi’s contributions to the field. The essay can be found at this link, “Kinji Imanishi and 60 years of Japanese primatology.”

I’m not too certain about Imanishi’s education. The piece indicates he was trained to be an entomologist. I deduce he specialized in ecology and animal behavior, because the review says he used to study Mongolian horses before he focused on primates. After his shift, Imanishi spent the rest of his life investigating the origins of human society by observing primates.

Anyways, the piece explains the various research projects after he started studying primates. This was three years after the end of the Second World War. Imanishi established several methodologies such as individual recognition, habituation and long-term observations, which are now standard techniques in the study of nonhuman primates.

Imanishi’s research also gave us insight to the mating habits of Japanese monkeys, their matrilineal societies, social hierarchies, and most importantly — the potato-washing behavior that is considered a proto-cultural behavior. You may have not known this, but this behavior, recorded by Satsue Mito, a student of Imanishi, in September 1953, is the first documented example of a cultural phenomena in nonhuman animals.

In February 1958, Imanishi traveled to Gombe, two years before Jane Goodall began her research. The photo below is from March 6th, 1958, where Imanishi (center) is pictured in Uganda, observing gorillas.

After his trip, he met up with Clarence Ray Carpenter, another primatology pioneer. Despite the death of Carpenter’s son against the Japanese during WWII, Imanishi was welcomed — a true testament of how science prevails. Imanishi gave the inaugural issue of Primates to Carpenter. Imanishi meet up with Louis Leakey and Sherwood Washburn, two big names in anthropology.

Imanishi was a true academic. He was inspired by other academics like Einstein, which motivated him to understand the world around him. If you want to know more about Imanishi, I recommend you check out this digital archive of his field notes.

Matsuzawa, T., McGrew, W.C. (2008). Kinji Imanishi and 60 years of Japanese primatology. Current Biology, 18, R587-R591.

Charlie Rose interviewed Emmanuel de Merode of WildLifeDirect, Brent Stirton and Godefroid Wambale four days ago — three men who know about the massacre of gorillas that happened last year in Virunga National Park. Their interview covers their account of the day where six gorillas were killed.

I’m very pleased with this interview, and even more displeased at Georgianne Nienaber’s comment. Nienaber is an ‘investigative environmental writer’ and tactiless opponent to WildlifeDirect and the ICCN rangers. She says that the arrest of Honore Mashagiro in March of 2008 in relation to these killings was all a setup and masterminded by the strategic interests of white supremacists — and the hero, Paulin Ngobobo is nothing but a figure head. I think she’s smoking crack. She’s using this excellent discussion on gorilla conservation with a major news source to leverage her own conspiracy theory, that is ‘founded’ on no evidence, whatsoever.

John Flynn, André Wyss, John Finarelli, and Karen Sears have been studying the brains of the ancestors of modern Neotropical primates and their early Old World fossil simian counterparts. They were able to determine that the brains of platyrrhines of the Americas were as small as those of the catarrhines of Africa and Eurasia, which suggests that there was independent evolution of brain size increase in New and Old World anthropoids.

The published their results in the American Museum of Natural History’s journal, Novitates. The title of the paper is, “Estimating body mass in New World “monkeys” (Platyrrhini, Primates), with a consideration of the Miocene platyrrhine, Chilecebus carrascoensis,” and it is open access. Flynn and colleagues made 80 measurements from the skulls, jaws, and teeth of 17 different species of living New World monkeys that ranged across the full spectrum of body sizes and calculated the encephalization quotients (E.Q.’s) — the ratio of brain size relative to their body size.

They took this matrix of E.Q.’s and applied it on the skull of a primitive primate dating to 20 million years ago, the early platyrrhine Chilecebus carrascoensis. Chilecebus is the oldest and most complete well-dated primate skull from the New World. It was described by Flynn and collaborators in 1995 in this Nature paper, “An Early Miocene anthropoid skull from the Chilean Andes.” Their results of the new paper showed that Chilecebus weighed around 583 grams and had an E.Q. ratio of only 1.11—a much smaller relative brain size than any living New or Old World anthropoid, which have E.Q.’s ranging from 1.39-2.44. This suggests that the larger brain sizes seen in both groups today evolved independently.

Sears, K.E., Finarelli, J.A., Flynn, J.J., Wyss, A.R. (2008). Estimating body mass in New World “monkeys” (Platyrrhini, Primates), with a consideration of the Miocene platyrrhine, Chilecebus carrascoensis. Novitates, 3617, 1-32.

Flynn, J.J., Wyss, A.R., Charrier, R., Swisher, C.C. (1995). An Early Miocene anthropoid skull from the Chilean Andes. Nature, 373(6515), 603-607. DOI: 10.1038/373603a0

I used to work at the Gorilla Foundation, and am still on their organizational mailing list. This weekend they sent me an email announcing a fundraiser they setup for the Mefou Sanctuary in Cameroon on Wednesday, July 9th, 2008. Specifically the event is setup to raise money for their infant gorilla nursery.

The event will be held at 8:30 p.m. to midnight at Doc’s Clock (2575 Mission St., San Francisco, CA). Doc’s Clock has offered $5 toward the fundraiser for everyone that walks in tomorrow night. This is an extremely generous gift and will help the get $19,750 worth of materials needed to build the nursery.

I’m very excited about this fundraiser, and have a prior obligation that will end around 9:30 p.m. but I plan to attend after that. So, if you are in the Bay Area tomorrow night and would like to help out, please attend!

Anthropology.net blogger German Dziebel sent me this link about the dim future of orangutans in Indonesia, Brunei, and Malaysia. Afarensis has also covered this news. The results of a new survey of orangutan populations have been published in the journal Oryx. I don’t have access to the early advance view of the paper, but one of the authors of the paper, Serge Wich, discussed his results to the Associated Press,

“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