Discoverer of ancient human ancestor retires after 50 years of teaching, lecturing worldwide
Donald Johanson visits the Hadar archaeological site in the Afar Triangle region of Ethiopia in 2024, where he discovered "Lucy" 50 years ago. Photo by Steve Filmer/ASU
Most famous for finding the 3.2 million-year-old human ancestor known as Lucy, Donald Johanson’s legacy at Arizona State University goes far beyond fossils.
As founding director of the Institute of Human Origins, he has dedicated his life to researching the origins of humankind and helping other scholars conduct expeditions all over the world. He has co-authored six books, including the National Book Award-winning “Lucy: The Beginnings of Humankind (with Maitland Edey),” and is currently working on his autobiography.
“I found science interesting even as a child, especially the fossils of human ancestors that were being found in Africa,” said Johanson, now an emeritus professor at the School of Human Evolution and Social Change.
“To be able to travel there and do research was tremendously exciting. After I found Lucy, reporters always asked, ‘What do you think you’ll find next?’ and I always said, ‘The unexpected.'”
For Johanson, retirement does not mean he will be leaving the field altogether — he will continue to serve on the board of IHO and travel and lecture.
“Paleoanthropology is something I will be fascinated with until my death.”
ASU News spoke with Johanson about his career and legacy.
Note: Answers have been edited for length and clarity.
Question: How did you become interested in science?
Answer: When I was in elementary school in Connecticut, I had an enthusiastic teacher who was excited about basic science; he really inspired me. I became obsessed with the world of science. I was fortunate to meet an anthropology professor who lived nearby — Paul Leser. My father died when I was 2 years old, and I never knew him, but this man gave me the greatest gift in the world: access to his library. He had books from the floor to the ceiling in every room in his house, and said, "Read what you want."
As kids, one of the questions we ask is, "How did we get here?" and Professor Leser pointed me to a thin little book by Thomas Henry Huxley from 1863 called “Man's Place in Nature.” Its basic premise, so revolutionary at the time, is that we humans share a common ancestor with the African apes. This was my moment of enlightenment. I decided I wanted to be an anthropologist and find fossils that would expand our understanding of who we are and where we came from.
Q: What brought you and IHO to Arizona State University?
A: In the early 1980s, I founded the Institute of Human Origins, an organization fully dedicated to the study of paleoanthropology that embraced a variety of specialties in the Earth and biological sciences. In the mid 1990s, my colleague, Professor Geoff Clark, informed me that ASU’s department of anthropology wanted to expand their faculty in paleoanthropology. The Berkeley-based IHO team and board of directors met with faculty and ASU President Lattie Coor, and together we developed a public-private partnership between ASU and the IHO Research Council. Largely due to President Crow’s passionate interest in how humans came to be, IHO is one of the preeminent research organizations in the world devoted to the science of human origins. It’s what I’m most proud of.
Q: Take us back to the start of your academic career. Why did you go to Africa to look for fossils?
A: As an undergraduate student studying anthropology and geology, I was aware that Professor F. Clark Howell was leading expeditions to Ethiopia, where human fossils were being discovered. I knew that he wasn’t going to knock on my door and say, “Hey, want to go to Africa with me?” So I called him. I said, “You don't know me, but I’m a student at the University of Illinois, and I’d like to meet you.” He was very welcoming and invited me to apply for graduate studies at the University of Chicago. Learning about my excavation experience, he graciously invited me to participate in fieldwork in the Lower Omo Valley of Ethiopia. While in Africa, we visited important collections of human fossils in Kenya and South Africa.
My time in Africa cemented my fascination with Africa and the story it reveals about how we became human. At the invitation of my late colleague and friend, Maurice Taieb, I joined a small expeditionary team that assessed the potential for paleoanthropological work in the Afar Triangle, in the northeastern extremity of Africa’s Great Rift Valley. After visiting incredibly fossil-rich geological deposits, Maurice established an international team of scholars to more deeply explore this region. In 1973, I found the first fossil human in the Afar, a knee joint (now dated to 3.4 million years).
Q: How did you find the Lucy fossil skeleton?
A: In 1974, on our second expedition to the Afar Triangle, I was out surveying with one of my graduate students, Tom Gray. Our task was to properly position on our maps the discovery of a nearly complete pig skull from the previous year. As we looked around that day, there weren't many fossils. Around noon, after scanning the surrounding area under 110 degrees, I looked over my right shoulder and spotted a fragment of an arm bone. Crouching down, I retrieved it and immediately knew it wasn’t a monkey or an antelope or any other mammal, because the anatomy indicated it had belonged to an ancient human.
I turned it over. I saw the anatomy so distinctive of a human skeleton, of a human ancestor skeleton. Looking up the slope, other fragments came into focus: part of a femur, chunks of mandible, shards of a cranium. It took me two months in the field to find this fossil, but there at my feet was my childhood dream. While the team celebrated that evening this remarkable discovery, we listened to "Sgt. Pepper’s (Lonely Hearts Club Band)" playing on my cassette player. The diminutive size of the bones suggested that the skeleton was of a female, and a member of the team suggested, “Why don’t you call her Lucy, after ‘Lucy in the Sky with Diamonds'?" And that is how she got her name.
Q: How old is she and what is so special about her?
A: We know from the geology that Lucy is 3.18 million years old, and she comprises about 40% of a single skeleton. Although we have since found hundreds of other fossils of her species, she is still the most complete adult Australopithecus afarensis specimen. Importantly, she answered the age-old question: What came first, upright walking or larger brain? Since she was a biped with a small brain, we now know that bipedalism came first.
Fifty years ago, we postulated that she represented the last common ancestor of two lineages: one that went extinct, and one that eventually became us — Homo sapiens. You know, in science, lots of theories fizzle out as new information or data become available. But 50 years later, Lucy is still sitting in her place on the human family tree.
Watch the PBS special on the 50th anniversary of the discovery of Lucy here.
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