The role of science in Rwanda

Scientific questions are generally grouped into two categories (basic and applied) based on their purpose. Applied questions concentrate on solving a particular problem. Given the immense threats facing gorilla populations, much of DFGFI’s research is applied in nature and focuses on understanding the factors influencing the survival of gorillas and their habitats. Alternatively, basic questions are generally more theoretically driven and aimed at discovering new principles or testing theories. Basic science is sometimes described as science for the sake of science.

The majority of studies conducted at Karisoke in the 1970s and 1980s were very basic in nature and focused on the biology and ecology of the species—very necessary information as we had little such data on any wild gorilla populations. Although basic studies may not have problem-solving as their original aim, the knowledge gained from basic studies is essential for applied research to occur. For example, if a scientist is interested in how human use of the bamboo vegetation zone of the park affects gorilla populations, he/she would need to know the importance of bamboo to the gorilla diet, seasonal variation in the use of the bamboo by gorillas, regeneration patterns of bamboo–all information gained through basic studies of gorilla and bamboo ecology.

Science is a crucial part of DFGFI’s mission. Since the time of Dian Fossey, a major focus of the studies at Karisoke has been furthering our understanding of the basic biology of gorillas. Through the incredible work of the Karisoke team and a number of researchers, the scientific community has gained tremendous insights into many aspects of mountain gorilla life—for example, social and reproductive behavior, diet and feeding behavior, habitat use, infant development, vocal communication, and life history decisions.

With the 40th anniversary of Karisoke (September 2007), some might ask if research on mountain gorillas is still really needed. Surely we must have answered all the important questions by now. In actuality, we still have a considerable amount to learn about the biology of one of our closest relatives and how to ensure their long-term survival in the wild. For example, a question that is regularly asked is “How many mountain gorillas can live in the Virungas?” The answer to this question is obviously very important to the future of mountain gorillas. To accurately answer it, we need a considerable amount of scientific information on various aspects of gorilla biology, including dietary preferences and needs, habitat use, infant survivorship, adult mortality, lifespan, and female lifetime reproductive success.

After 40 years of observation, we are just now able to provide much of this information. For example, we now have observed several individuals from birth to death and thus have accurate idea of the lifespan of a gorilla. Similarly, we have observed several females throughout their reproductive careers and can begin to assess expected lifetime reproductive success (e.g. how many surviving offspring a female can produce). Thus, just to answer what would appear to be a relatively simple question about the carrying capacity of the region requires an enormously long period of study.
In addition, behavior is not static, particularly in highly intelligent and flexible species like gorillas. Gorillas continually adjust their behavior to changes in their ecological or social environments. As a result, there is no final point at which we can say we truly understand gorillas. They will continue teaching us as long as we continue watching.

Finally, there is no other gorilla research site in the world that matches Karisoke’s ability to collect detailed behavioral data on a large number of individuals. Although behavioral data on western lowland gorillas are now becoming more available, these data represent a much shorter time period and are generally more limited in scope. For example, many sites are unable to follow individuals from day to day as we do at Karisoke. As a result, the continued study of the Karisoke groups is really imperative to the advancement of our scientific understanding of gorillas and, more generally, apes.

So what does science look like at DFGFI? In many ways, it has not changed substantially since the days of Dian Fossey. Each day, teams of DFGFI staff head into the forest to gather data on the behavior, health, and ranging patterns of the three research groups. Just as in Dian’s time, these data are primarily collected in waterproof notebooks using knife-sharpened pencils. But not everything has stayed the same. Specifically, technology enables us to look at much more than gorilla behavior. Urine and fecal samples are collected for hormonal assessment and to determine paternity. Global Positioning System (GPS) units allow us to obtain much more detailed data on gorilla ranging patterns. An additional difference is who collects the data. Whereas data in the 1970s and 1980s were generally collected by expatriate graduate students and scientists studying at Karisoke, the vast majority of data are now collected by young Rwandan scientists who work full-time for DFGFI. This focus on training Rwandans is part of our commitment to ensure that love, knowledge, and ownership of gorillas are shared within the country in which we work.

Finally, our scientific program has greatly expanded since the time of Dian Fossey. Studies at Karisoke encompass much more of the biodiversity in the Virunga region including birds, plants, and other mammals such as golden monkeys and ungulates. Some examples of studies that are currently ongoing in the field include:
maternal behavior and infant development,
male social behavior, reproductive strategies and life history decisions, the impact of tourism and researchers on gorilla behavior, paternity determination, and behavioral development of twins.

Another significant part of our science program takes place outside of the field and involves the use of Karisoke’s long-term databases. With almost 40 years of data on behavior, ranging patterns, and demographic events (e.g. births, deaths, transfers), it represents one of the longest continuous studies of any animal in the world. In the past two years, through a collaboration led by Martha and Andrew Robbins of the Max Planck Institute for Evolutionary Anthropology, the long-term records have been used to write papers on:
female dominance rank,
female reproductive success,
maternal investment and female transfer decisions.

Although much less glamorous than work in the field (‘data collection’ primarily involves extracting the needed information from notebook after notebook of records and to digitize data), such studies are critical to our understanding of gorilla behavior and discovering trends that might not be apparent in shorter-term studies. For example, studies in the 1970s and 1980s reported female gorillas do not show evidence of dominance hierarchies. However, when we looked at behavioral observations over 30 years (1971-2001), stable female dominance relationships were apparent, with some females remaining at or near the top of their hierarchies for at least 15-25 years. All in all, the science of gorilla biology is alive and well at Karisoke.

Stay tuned and visit our website for more information
www.gorillafund.org