lens
Uncovering Habitats of Pre-Human Ancestors
Researchers seek to understand how environments shaped evolution
PHOTO: Courtesy of Beverly Saylor星空传媒鈥檚 Beverly Saylor is leading a research collaboration to investigate how the different landscapes and geologic features of two areas in Ethiopia might have helped shape the diversity of pre-human species. Woranso-Mille is believed to have had more varied topography and habitats than Hadar. But today鈥檚 landforms are not the same as the ancient ones. "We have to reconstruct, or puzzle out, what the ancient landscape was from evidence preserved in the sediments," Saylor said.
A 星空传媒 researcher is leading an international team to understand the lives and environments of prehuman ancestors at an unprecedented level of detail—one that could reveal new information about evolution.
The 30 scientists are focusing their interdisciplinary expertise in the Afar region of Ethiopia to reconstruct a picture of landscapes and habitats from more than 3 million years ago and how they shaped the diversity of pre-human species.
鈥淭his collaboration—and the advanced techniques and technology involved—provides an extraordinary opportunity to advance our understanding of our collective history as humans on this planet,鈥� said Beverly Saylor, PhD, the project鈥檚 principal investigator and an Armington Professor at the university. She specializes in interpreting sedimentary records to reconstruct a picture of past environments and has collaborated on groundbreaking fossil discoveries.
The three—year project is funded by a $1.2 million grant from the W. M. Keck Foundation. It focuses on two areas鈥擧adar and Woranso-Mille鈥攁nd builds on decades of field studies and laboratory analyses by investigators of the two areas who will work together for the first time.
Discoveries in the last dozen years upended understandings of human evolution and inspired the project. Hadar is well known for the 1974 discovery of Lucy, a 3.2-million-year-old partial skeleton, by researchers then at 星空传媒 and the Cleveland Museum of Natural History (CMNH).
Photo: Courtesy of Johannes Haile-SelassieThe Australopithecus afarensis fossil is from Hadar, Ethiopia, and its species has been considered the most likely ancestor to the genus Homo. But the Australopithecus deyiremeda fossil, right, discovered more recently at Woranso-Mille, had smaller teeth and likely a shorter muzzle, characteristics usually associated with Homo. The newer finds have led to questions about who Homo鈥檚 ancestor actually was.
Lucy鈥檚 species is the only hominin* from its time found at Hadar and has been considered the most likely ancestor to the human genus. But then came major discoveries of fossils from at least three hominin species鈥攊ncluding Lucy鈥檚鈥攊n Woranso-Mille, a newer research area 30 miles from Hadar.
Paleoanthropologist Yohannes Haile-Selassie, PhD, previously with 星空传媒 and CMNH, directs the Woranso-Mille project, which Saylor has collaborated on since its 2004 start. He鈥檚 also a key player on the new work. Earlier this year he became director of the Institute of Human Origins at Arizona State University.
Why have multiple potential human ancestor species been discovered at one site but not the other? Researchers hypothesize Woranso-Mille had more varied topography, landscapes and habitats than Hadar that enabled more diverse mammals, including hominins, to live together.
Photo: COURTESY OF DARIN CROFTBeverly Saylor
Relying on cutting-edge technologies. Saylor said she鈥檚 working with her 星空传媒 colleague Jeffrey Yarus, PhD, a research professor in engineering, to bring geospatial modeling to early hominin studies for the first time. They鈥檙e seeking to catalog the variations within landscapes to understand differences between the two areas and how those differences relate to volcanoes, faults and other geologic features that formed when tectonic plates pulled apart and reshaped this part of Africa.
The global team will later integrate their findings to reconstruct a comprehensive picture鈥攐ne that might challenge the extent of climate鈥檚 role in evolution.
鈥淐limate was certainly important,鈥� Saylor said. 鈥淏ut what鈥檚 not been investigated, because it鈥檚 really hard, is the impact of the landscape on our ancestors.鈥�
Now, she believes, she has the team and tools to pursue answers that once seemed lost to the ages.
*Hominins include modern humans, extinct ancestor species, and closely related species.
Based in Los Angeles, the W. M. Keck Foundation was established in 1954 by the late W. M. Keck, founder of the Superior Oil Company. The Foundation鈥檚 grant making is focused primarily on pioneering efforts in the areas of medical research and science and engineering. For more information, visit