By Stuart Thornton
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R E S O U R C E L I B R A R Y A RT I C L E Case Study: Koobi Fora Research Project A case study that illustrates the Koobi Fora Research Project’s amazing finds in the field of paleontology. G R A D E S 6 - 12+ S U B J E C T S Geology For the complete article with media resources, visit: http://www.nationalgeographic.org/article/case-study-koobi-fora-research-project/ By Stuart Thornton Wednesday, May 16, 2012 National Geographic Explorer-in-Residence and paleontologist Meave Leakey works in the remote Lake Turkana region of Kenya and Ethiopia. She, her husband, Richard, her daughter Louise, and a team of scientists have been researching fossils in the Koobi Fora area of the Lake Turkana Basin for more than 30 years. Koobi Fora is a ridge of sedimentary rock on the eastern shore of Lake Turkana, Kenya. The Koobi Fora Research Project (KFRP), initiated in 1968, forms the backbone of the Turkana Basin Institute (TBI). Almost 10,000 fossils have been discovered in Koobi Fora, more than 350 from ancient hominin species. The investigation of the evolution of human beings and hominin relatives is the primary—although not the only—scientific goal of the KFRP. “The continued research in the Turkana Basin will further the global understanding of human origins and the context in which it occurred through the recovery and investigation of new fossil material from deposits in northern Kenya,” according to the project’s mission statement. Geography Located in northern Kenya, the Turkana Basin is a 70,000-square-kilometer (27,027-square-mile) region that is home to Lake Turkana, the most saline lake in East Africa and the largest desert lake in the world. The area includes three national parks: Sibiloi National Park, South Island National Park, and Central Island National Park. Lake Turkana, nicknamed the “Jade Sea” due to its striking color, is a major stopover for migrating waterfowl. The surrounding area is a major breeding ground for Nile crocodiles, hippopotamuses, and a range of venomous snakes. The basin surrounding Lake Turkana is arid and receives little rainfall outside the “long rain” season of March, April, and May. Due to the extreme climate conditions around Lake Turkana, there is a low human population in the basin. The people who live in the area are mostly small-scale farmers and pastoralists. The Turkana Basin has become known around the world for its amazing fossil deposits. In particular, the area has a wealth of hominin fossils that have contributed greatly to our understanding of human evolution. Assessment Even before the Koobi Fora Research Project began, the Turkana Basin was known for its fossils. A French expedition in 1902 and 1903 first discovered vertebrate fossils in the lower Omo Valley. (The Omo River flows south from Ethiopia into Lake Turkana.) During World War II, Allied troops stationed in southern Ethiopia collected fossils from the lake and its nearby hills. But it was a 1968 investigation of Lake Turkana—then known by its colonial name, Lake Rudolf —by paleontologist Richard Leakey that uncovered a cache of fossils that would lead to the start of the Koobi Fora Research Project. Flying over the region in a helicopter, Leakey noticed unusual rock formations on the eastern side of Lake Turkana. The features were thought to be igneous rock—hardened lava. To Leakey, however, the features appeared to be sedimentary rock, which is slow to accumulate and often preserves fossils. The 1968 expedition showed Leakey was right; the rocks turned out to be fossil-rich sediments. In addition to plant and animal fossils, Koobi Fora has yielded an array of hominin species: Homo habilis, Homo rudolfensis, Homo erectus, Paranthropus boisei, Paranthropus aethiopicus, Australopithecus anamensis, and Kenyanthropus platyops. The purpose of the Koobi Fora Research Project is nothing less than to uncover how we became human. “We are trying to find evidence of our ancestors in order to chart the evolutionary history of our species,” says Meave Leakey, who currently runs KFRP with her daughter and fellow Explorer-in-Residence, Louise. To fully understand how our species evolved, KFRP looks for clues to what the habitats of our ancient ancestors were like. “We ourselves have a very good field team who finds fossils, and we are trying to find actual fossil evidence of our ancestors,” Meave Leakey says. “But we are also interested obviously in the other fossils—the fossils of the fauna and of all the animals that lived alongside our ancestors—because from the evolution of these animals we can learn what may have happened during our own evolution, the evolution of our species.” Conflict Paleontologists, anthropologists, geologists, and other scientists involved with the Koobi Fora Research Project often have conflicting ideas about how things happened in the past. Following the scientific method, the project’s theories change and evolve as more research is conducted and the theories are tested by field work and new technologies. “Obviously there are many different ways of interpreting some of the evidence, and that’s why we are always looking for more, because we get closer and closer to the truth with the more evidence we find,” Leakey says. “Controversy is the word that is generally used when people come up with alternative theories, but that’s the way science progresses. It’s a normal process. People will interpret one set of evidence one way and other people another way. And then you find more evidence. And then you all come to an agreement, hopefully, in the end.” Two discoveries associated with the Turkana Basin are examples of conflict whose resolutions are being pursued through rigorous scientific inquiry and research. In 1984, TBI paleoanthropologists discovered “Turkana Boy,” a nearly complete 1.5 million-year- old skeleton of a hominin with proportions similar to our own. Turkana Boy is the most complete early human skeleton ever found. Despite Turkana Boy being one of the most- studied hominin fossils in history, paleoanthropologists still debate whether the specimen is Homo erectus or Homo ergaster. Other KFRP discoveries include species, such as Kenyanthropus platyops, found nowhere else in the world. There is only one K. platyops specimen, and it remains a source of scientific conflict. Some paleontologists—including Leakey—identify the skull as a unique genus (Kenyanthropus). Others say it is related to another branch of hominins, the australopithecines. Still others maintain it is not a unique species at all, but the deformed skull of a familiar hominin, Australopithecus afarensis. Stakeholders Since the Koobi Fora Research Project is attempting to understand human evolution, all of humanity could be affected by the project’s findings. Paleontologists and paleoanthropologists: Discovering and documenting the evolution of Homo sapiens sapiens, our own species, is one of the great scientific endeavors of the 20th and 21st centuries. Paleoanthropologists are continually searching for clues in the field, as well as reviewing earlier finds with new technology, to understand how H. sapiens sapiens evolved from earlier species. The project is important because it helps us understand our shared past and may help us realize how our species should proceed into the future. “If you believe as I do that understanding our past is important, then our work is important,” Leakey says. “We have discovered an enormous number of fossil human ancestors that were unknown before,” she continues. “We have demonstrated that the evolutionary past of humans is much like that of other animals. There were radiation and extinction events. Our part is really no different from other animals in that sense.” Archaeologists, geologists, climatologists, and other scientists: How early hominin species interacted with the environment and other species—and each other—is a major focus of the KFRP. Many other projects at the Turkana Basin Institute complement the work of the KFRP in this way. Archaeologists study tools and artifacts, such as fish hooks and pottery. Geologists study how the landmass of Eastern Africa developed, and how it is rifting now. Climatologists study the varied history of the Turkana Basin, following the expanding and receding shores of the ancient lake. Turkana Basin Region Residents: Meave Leakey notes that the Turkana Basin Institute trains the region’s residents about fossil finding, fossil preparation, fossil reconstruction, and even how to curate fossil exhibits. “We are trying very much to involve and educate the local people,” Leakey says. “And we are trying also to have the local people assisted by the work that we are doing.” Conflict Mitigation Any conflicting ideas or theories that emerge from the work of the Koobi Fora Research Project are resolved by scientists making more discoveries and conducting more research. “The KFRP has discovered and recovered the majority of the fossil collections, hominin and non-hominin, that are known from the lake basin,” Leakey says. “These are the basis of our knowledge of the fauna and of the evolution of the animals found in East Africa today. We continue to recover, as do others, new fossil discoveries and new information that enable us to test past hypotheses and make new ones. Sometimes we are wrong, but that is the way with science. Answers are built on what we know at any particular time. With new discoveries, past ideas and theories are adjusted and refined.” For instance, paleoclimatologists and paleobotanists working with the KFRP have uncovered significant faunal turnover between 5 million and 7 million years ago. The humid jungle habitat slowly gave way to more open environments. Grasslands became more prominent. This environmental change is now posited as one of the primary reasons hominin species became bipedal, or walking upright on two legs.