March 28, 2012

At Karisoke, Gorilla Bones Are Telling Their Stories

Bones can tell many stories, especially with new technology that was not available in the 1960’s when Dian Fossey began to collect and study gorilla skeletons. In 2009 a team of scientists began the Mountain Gorilla Skeletal Preservation and Research Project to continue her work, coordinated by George Washington University’s Center for the Advanced Study of Hominid Paleobiology (CASHP) in collaboration with the Rwandan park authority (RDB) and other partners and facilitated by the Dian Fossey Gorilla Fund International.

The first step was to exhume bones that were buried in a special graveyard near the Karisoke Research Center’s original site in Rwanda’s Volcanoes National Park. Each summer, researchers from several universities have been carefully digging up and cleaning the skeletons of some 70 gorillas that Dian Fossey and her successors buried there from 1967 to 1994, as well as those buried more recently in other locations by park authorities and veterinarians with a view to preserving them for later study.

The bones are laid out for processing in Karisoke’s garage. There, the research team arrives for three months each year to painstakingly assemble the skeletons, which each contain 200 different bones if complete. They photograph and catalogue every skeleton and use microscopic analysis, three-dimensional laser scanning and other tools to reveal the stories inscribed in the bones. A collection of other mammal bones is also on hand for comparison. During the summer of 2011, the team excavated the skeletons of nine mountain gorillas, six golden monkeys and one bushbuck. The collection now holds 96 mountain gorilla skeletons, with more to come in 2012.

The project is important to Rwanda. It was initiated by Dr. Antoine Mudakikwa, RDB’s (then ORTPN’s) chief veterinarian and head of ecological monitoring, research and health, who realized the value of the bones. In 2011, the work was assisted by three undergraduate interns from two Rwandan universities. Three graduate students from the United States trained the interns in bone excavation, treatment and analysis and worked with them in the field.
One of the Americans, Katie Murtough, observed in CASHP’s student blog that “one day, these students and others like them will take over responsibility for managing this resource, developing exhibits at a recently-opened museum of natural history in Kigali, and generating new research that can contribute towards Rwanada’s efforts to ensure the long-term survival of its mountain gorilla population.”

By examining the marks on bones and teeth that reflect injuries, births and other events, and comparing them with the field notes recorded over the decades by Fossey and her successors at Karisoke, the scientists can complete their understanding of each gorilla’s life and the impact of environmental change, diet, stress and disease on the gorillas, which will contribute to conservation planning. The analysis will also yield a more accurate picture of mountain gorilla development, to help in calculating the age of individuals whose birth date is not known and in evaluating factors affecting gorilla development. The project’s findings are already contributing to research, not only on gorillas but also on our understanding of human evolution. A paper on brain growth in Virunga mountain gorillas will be published next month, and a scientist from the Smithsonian National Museum of Natural History is preparing a paper on eastern gorilla evolution and the origins of Grauer’s gorillas, based on evidence from hand and foot bones.

“Over the past four years, the Mountain Gorilla Skeletal Preservation and Research Project has established the world’s largest and most complete collection of mountain gorilla skeletons,” says Murtough.

Core partners conducting the Mountain Gorilla Skeletal Preservation and Research Project include the Tourism and Conservation Department of the Rwandan Development Board; George Washington University; New York University College of Dentistry; and the Mountain Gorilla Veterinary Project, as well as the Fossey Fund and Karisoke. Collaborating partners are the Institute of the National Museums of Rwanda; the University of Indianapolis; the Smithsonian’s National Museum of Natural History; and New York University. Major funding was provided by the Leakey Foundation, the National Geographic Society, and the National Science Foundation.