The work was conducted by the Solo River Terrace Project, an international group of scientists directed by anthropologists Etty Indriati of Gadjah Mada University in Indonesia and Susan Antón of New York University. Briana Pobiner, paleoanthropologist at the Smithsonian’s National Museum of Natural History in Washington, D.C. is the project’s archaeologist.

Image right: A lifelike bust of Homo erectus at the Smithsonian’s National Museum of Natural History. (Artist: John Gurche; Photo: Chip Clark)

Homo erectus is widely considered a direct ancestor of modern humans—it resembles modern humans in many respects, except for its smaller brain and skull shape—and was the first hominin, or early human, to migrate out of Africa, approximately 1.8 million years ago. Homo erectus went extinct in Africa and much of Asia about 500,000 years ago, but appeared to survive in Indonesia until about 35,000 to 50,000 years ago at the site of Ngandong on the Solo River. These late members of Homo erectus would have shared the environment with early members of our own species, Homo sapiens, who arrived in Indonesia by about 40,000 years ago.

However, findings by the Solo River Terrace Project show that Homo erectus‘ time in the region ended before modern humans arrived there. The analyses suggest that Homo erectus was gone by at least 143,000 years ago—and likely by more than 550,000 years ago. This means the demise of Homo erectus occurred long before the arrival of Homo sapiens.

“Thus, Homo erectus probably did not share habitats with modern humans,” said Indriati.

The Solo River Terrace Project’s investigations occurred in Ngandong and Jigar, two sites in the “20-meter terrace” of the Solo River. The sediments in the terrace were formed by the flooding of the ancient river, but currently sit above the Solo River because the river has cut downward through time. The terrace has been a rich source for the discovery of Homo erectus and other animal fossils since the 1930s.

As recently as 1996, a research team dated these sites of hominin, or early human, fossils to as young as 35,000-50,000 years old. The analyses used a technique that dates teeth, and thus provided ages for several animals discovered at the sites. However, other scholars suggested the sites included a mixture of older hominins and younger animals, raising questions about the true age of the hominin remains.

Since 2004, team members have conducted analyses of animal remains, geological surveys, trenching, and archaeological excavations. The results from all of these provide no evidence for the mixing of older and younger remains.

“The postmortem damage to the animal remains is consistent and suggests very little movement of the remains by water,” Pobiner explained. “This means that it is unlikely that very old remains were mixed into younger ones.” [See Briana at work in this video.]

In addition, clues from the sediments exposed during excavation suggest to the projects’ geoarchaeologists, Rhonda Quinn, Chris Lepre, and Craig Feibel, of Seton Hall, Columbia, and Rutgers universities, that the deposits occurred over a short time period. The teeth found in different excavation layers at Jigar are also all nearly identical in age, supporting the conclusion that mixing across geological periods did not occur.

– Source: New York University

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Image left: A hyper-realistic bust of Homo neanderthalensis by artist John Gurche in the David H. Koch Hall of Human Origins.

Based on decades of cutting-edge research, the 15,000-square-foot Hall of Human Origins offers visitors an immersive, interactive journey through 6 million years of human evolution that spells out how defining characteristics of the human species have evolved during millions of years in response to a changing world. Inside are stories of survival, extinction and evidence of how environmental change may have shaped the evolution of new adaptations and the origin or extinction of early hominin species, as well as the emergence of our species, Homo sapiens. Visitors connect with their distant ancestors through life-size forensically reconstructed faces of early human species and learn about major milestones in the origins of human beings.

Other key features in the exhibition include interactive snapshots in time based on actual field sites where research is being conducted, a display of more than 75 skulls (exact replicas), an interactive human family tree showcasing 6 million years of evolutionary evidence from around the world, a “One Species Living Worldwide” amphitheater show and a special “Changing the World” gallery, in which visitors can address questions and issues surrounding climate change and the impact of humans on the Earth.

Video: Curator Rick Potts talks about the new David H. Koch Hall of Human Origins

“The theme of the exhibition, ‘What Does It Mean to Be Human?,’ is one of the most profound questions humans have asked over thousands of years and is informed by philosophy, religion and the arts and sciences,” said Rick Potts, director of the Human Origins Program and curator of anthropology at the museum. “Our goal is to provide a solid foundation for the public to explore the scientific contributions to answering this question.”

Image right: A bust of Australopithecus afarensis by John Gurche.

“What our exhibit does, is something that no other exhibit in the world does,” Potts continues. “ It’s not just about the discovery of a particular fossil human, it’s not just about debates that rage in scientific circles about our family tree and who was related to whom of the early species of fossil humans.” Rather this exhibit is “about the emergence of human characteristics, the things that define every single human being on earth today and it allows people the chance to explore the antiquity of walking upright on two legs, when we started making tools and the changes in technology over time, when our brains became large, the origins of art and our ability to use symbols and language. It allows the visitor to explore that deep antiquity and to see that everything didn’t happen all at once but rather things occurred over a 6-million year period in accumulating the characteristics of what it means to be a human being today.”

Image left: An evolutionary comparison (from left to right: Homo erectus, 1 million years old; Australopithecus afarensis, 2.5 million years old; Homo neanderthalensis, 100,000 – 32,000 years old)

Also, the exhibition contains a series of interactive stations to help visitors explore scientific evidence about the lives of early human ancestors and have fun while doing it. For example, there is a face-morphing station where visitors can see their faces transform into an ancient species of their choosing. Other features include interactive snapshots in time using the actual field sites where research is conducted; an interactive human family tree showcasing 6 million years of evolutionary evidence; a “One Species Living Worldwide” theater show; and a special “Humans Change the World” gallery.

Visitors can dig deeper online through the Human Origins Web site, http://humanorigins.si.edu, which features the Human Origins research program, collections and field sites—including podcasts and diaries from the field. They can engage onsite and online with science and scientists and go behind the scenes into the field, the lab or a unique, interactive museum experience that illuminates the major milestones in the origin of human beings.

By presenting the scientific findings and process of discovering how our species has evolved over time, the exhibition, “Human Origins: What Does It Mean to Be Human?,” takes the most comprehensive perspective on human beings of any Smithsonian exhibition.

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Image: This illustration depitcs a section of the exhibit that highlights how modern humans are the one remaining species of a diverse family tree.

The $20.7 million hall will be complemented by ongoing human origins research and education programs, which are all key components of the museum’s broader initiative, “Human Origins: What Does It Mean to Be Human?” The initiative focuses on the epic story of human evolution and how the defining characteristics of the species have evolved over 6 million years as its ancestors adapted to a changing world.

 Visitors to the 15,000-square-foot Hall of Human Origins will be immersed in a unique, interactive museum experience illuminating the major milestones in the origin of human beings and the drama of climate change, survival and extinction that have characterized humans’ ancient past. On entering the exhibition from the Sant Ocean Hall, visitors will travel through a dramatic time tunnel depicting life and environments over the past 6 million years. Visitors will also engage with life-size forensically reconstructed faces of early human species, all designed to provide visitors with a sense of personal connection as they look into the eyes and faces of their distant ancestors.

Image: This illustation shows a section of the exhibit that communicates the message that human characteristics evolved over millions of years.

Other key features in the exhibition include interactive snapshots in time using the actual field sites where research is being conducted, a display of more than 75 skulls (cast reproductions) and an interactive human family tree showcasing 6 million years of evolutionary evidence from around the world, a “One Species Living Worldwide” amphitheater show and a special “Changing the World” gallery, in which visitors can address pressing questions and issues surrounding climate change and humans’ impact on the Earth.

 “The study of human origins is among the most vibrant fields of science and one that draws much public curiosity,” said Rick Potts, director of the Human Origins Program and curator of anthropology at the museum, whose research and vision is the foundation of the Smithsonian’s Human Origins Initiative. “Our hope is that the exhibition will expand knowledge and understanding about our defining cultural and biological characteristics and how those traits emerged during the past 6 million years—one of the most dramatic eras of environmental change in our Earth’s history.”

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