translate

Site update

Since I have been really terrible at updating the blog (but pretty good at keeping up with the facebook blog posts) I've added the widget below so that facebook cross posts to the blog.

You shouldn't need to join facebook but can just click on the links in the widget to access the articles. If you have any problems or comments please mail me at arandjel 'AT' eva.mpg.de.

Thursday, February 21, 2008

Chimps Eat Dirt, Leaves to Fend Off Malaria


From National Geographic News
by Scott Norris

Chimpanzees in Uganda swallow mouthfuls of dirt to "self medicate" against malaria, according to a new study.

Clay soils consumed by both chimps and humans in Uganda's Kibale National Park contain high concentrations of the mineral kaolinite, a main ingredient in some anti-diarrheal medications.

Experts had previously suggested that chimps ate the fine-grained clay to help ward off intestinal ailments or to obtain added minerals in their diet.

But a French team recently observed that the chimps eat dirt before or after consuming leaves from the Trichilia rubescens plant, which contains potent medicinal chemicals.

Eating the bitter vegetation alone gives the chimps no health benefit, researchers say.

Instead the plant's malaria medicine is activated when fine soil particles bind with chemicals in the leaves.

Chimps often select dirt that has been exposed on the roots of newly fallen trees, added study co-author Sabrina Krief, of the Muséum National d'Histoire Naturelle in Paris.

"This may be to avoid worms, bacteria, and stones," she said.

Krief and colleagues described the research online in the January issue of the journal Naturwissenschaften.

In humans, soil consumption—or geophagy—has often been viewed as a sign of metabolic disorder or even mental illness.

But the practice is relatively common among animals and is now understood to yield important health benefits.

In parrots and macaws, for example, clay particles are thought to help neutralize toxins present in some favored food sources.

Soil-eating may also provide a soothing coating to the animals' digestive tracts.

In Uganda, however, Krief and colleagues suspected that the chimps were eating soil for other reasons than simply to combat indigestion.

Like humans, chimps can suffer the potentially fatal effects of malaria, although the types of Plasmodium parasites that cause the disease in chimps are different from the four known to infect people. (See a close-up image of malaria parasites attacking a human's red blood cells.)

In previous laboratory studies, Krief's team had found that extracts of the Trichilia plant were effective in fighting the parasite that causes malaria in chimps.

"I noticed that the chimps often eat soil just before or after eating Trichilia leaves," Krief said. "I wondered what might be the effect of mixing the two substances."

To investigate, Krief and colleagues constructed a laboratory model that duplicated chimpanzees' chewing and digestion.

The researchers ground up leaves and soaked them in an acid solution similar to the chimps' digestive fluids. The mixture was then tested for its ability to kill the malarial parasite.

Solutions of artificially digested leaves without soil showed no anti-malarial activity.

But when samples of the soil consumed by the chimps were added to the mix, the researchers found a strong disease-fighting effect.

Chimps and other apes may treat themselves for a variety of ailments by consuming plants, earth, and other materials, experts say.

In another part of Africa, chimps are known to swallow certain leaves to help rid themselves of intestinal parasites.

Previous work by Krief and others had shown that of the 163 plant species Kibale chimps are known to eat, at least 35 are used in humans' traditional medicine.

"The shared use of plants by humans and apes shows how the tropical forest is a unique resource for wildlife, local communities, and western medicine," Krief said.

Jim Moore is an anthropologist at the University of California, San Diego, who was not involved with the new study.

"It's been known for a long time that chimpanzees selectively eat certain plants in ways and at times that only really make sense if they are self-medicating," Moore said.

"This paper is the first I'm aware of to suggest synergistic action of soil and a putatively medicinal plant, and that's important."

But Moore noted that the anti-malaria effect has only been shown in the researchers' model and not yet in living chimps.

"It isn't clear that chimpanzees are seeking the synergy [between leaves and soil]," Moore said. "The paper isn't persuasive in eliminating other hypotheses for geophagy."

Tuesday, February 19, 2008

First Observed Birth of a Western Lowland Gorilla in the Wild

Here, Mowane is seen riding her mother Malui's back.
Picture © Kate Bracewell, Dzanga-Sangha Protected Areas

from wwf.org
(Congo Basin > Updates)
January 22, 2008

Just last month, staff of the WWF-funded Dzanga-Sangha Primate Habituation Programme witnessed the birth of a new infant into the Makumba group of western lowland gorillas, which lives in the Central Africa Republic's Dzanga-Ndoki National Park. The newborn was named Mowane - meaning "gift of God" in the local Bantu language.

Malui gave birth to Mowane in a tree nest as Makumba - her father - fed nearby. Malui was then observed biting Mowane's umbilical cord free, after which she climbed down and made three more nests on the ground. At this point her other offspring came and watched Malui groom their new sister. Like other mother-offspring pairs, Mowane has inherited her mother's unique nose pattern - v-shaped nostrils with distinct line-markings above.

The mother and infant are doing well and staying close to Makumba, who is taking his protective role seriously - a week after the birth he was observed leading his group away from the threat of a solitary male. Mowane is getting stronger by the day and has graduated from being carried on Malui's belly to being on her mother's back, and more recently on her arm.

Makumba's group is one of four in varying stages of habituation, along with a group of agile mangabey monkeys. Established in 1997 and funded by WWF, the Dzanga-Sangha Primate Habituation Programme (PHP) works to gradually acclimate western lowland gorillas to human contact for tourism and research. Through habituation, the program can help increase the economic values of parks in the Dzanga-Sangha region, generate ecotourism income for local communities, and increase support for gorilla conservation. The PHP is part of a larger Dzanga-Sangha Protected Areas Ecotourism Programme, managed in partnership with the government of the Central African Republic, WWF and German nongovernmental organizations.

WWF's support of PHP is part of our work in the Congo Basin region, whose dense forests extend almost 500 million acres and span the boundaries of Cameroon, the Central African Republic, the Democratic Republic of the Congo, Equatorial Guinea, Gabon and the Republic of the Congo. WWF has worked for more than 30 years to protect the Congo Basin and continues to be active in the field, engaging conservation partners and protecting great apes for future generations.

Saturday, February 16, 2008

Nerd Music



microsatellites - electropherogram images translated into sound by coagula light
by Molecular code

molecular code - annoying labnoise turned into music
based on milkcrate, the idea is two use noise & sounds produced by devices/images/animals from a lab and modify those to create some nice electronic music

To check out more tunes by molecular code (including an ABI Prism 310 & drosophila) visit their myspace page

Friday, February 15, 2008

Very Important Scientists of the Month: Thomas Breuer & Mireille Hockemba


Doin' it gorilla-style
from New Scientist.com
Michael Marshall, online editorial assistant

Well, we had to have a Valentine's Day post, so here it is. For the first time, scientists have photographed wild gorillas mating face-to-face (see Photo).

Thomas Breuer & Mireille Ndoundou Hockemba, of the Wildlife Conservation Society, observed the behaviour during a long-term study of western gorillas in the Republic of Congo. They reported their findings in the April 2007 issue of Gorilla Gazette, but the photos have only now been released.

Face-to-face mating is unusual among primates. It's technically called ventro-ventral copulation, and is only frequently observed in bonobos and, of course, humans. Most primates prefer the dorso-ventral position, which our more plainly spoken readers may know as doggie-style.

The gorilla shown in the picture, who researchers call Leah, is something of a celebrity. In 2005 she was the first wild gorilla observed using a tool - she dipped a long stick into a pool of water to test its depth before wading in.

The story got me wondering about the evolutionary reasons for these different mating behaviours. On the face of it, you could argue that one sexual position is pretty much as good as another (unless you're endangering yourself by performing weird contortions, which seems to be a purely human preoccupation). After all, the point is to deliver the sperm to the egg in as efficient a way as possible, and so long as the male is fully inserted, what difference can it make?

However, some species copulate for reasons other than breeding. Famously, bonobos engage in large quantities of sex, partly as a way of forming and maintaining social bonds. They have also been observed having sex face-to-face, not to mention a whole catalogue of other activities including (and before we get complaints, this is the official term) penis fencing.

That suggests to me that face-to-face mating could have evolved to help strengthen emotional and social bonds, and promote teamwork. Focusing on your partners face would presumably emboss it in your memory, helping you to form a relationship with them. It has also been shown that eye contact makes you more attractive. Why this is so is unclear, but might it be a marker of openness and interest?

Oh, and in case anyone is wondering, the third gorilla (on the right of the picture) is Leah's young daughter Nancy. So probably not a gorilla peeping Tom - though given the range of sexual behaviours observed in primates, I won't be surprised if some of them engage in voyeurism as well.

more reports on Thomas & Mireille's work can be found at the links below:

*nature.news: Gorillas in the missionary position
*sciencedaily.com: Unique Mating Photos Of Wild Gorillas Face To Face
*reuters.com: Gorillas caught in face-to-face love action
*nationalgeographic.com: Gorillas Photographed Mating Face-to-Face -- A First
*NY Times blog: The Ultimate Valentine Card: Full-Frontal Gorilla Love