Telling the tale of human origins, one fossil tooth at a time

September 16, 2026

AI Summary

5 min read

In the blistering heat of Ethiopia's Afar region, paleoanthropologist Johannes Haile-Selassie spends most of his time doing something that looks nothing like the dramatic excavations people imagine: he walks. For 99 percent of fieldwork, he says, "I was just walking around with my eyes on the ground looking for fossils." The director of the Institute of Human Origins at Arizona State University has helped discover some of the most important hominid fossils ever found—including the 4.4 million-year-old partial skeleton known as Ardi and the 5.8 million-year-old Ardipithecus kadabba—but his path to those discoveries began with a degree in history and a lucky assignment to a paleoanthropology lab.

The art of spotting a fossil tooth

Finding fossils is less about digging and more about training your eyes to see what matters. Haile-Selassie explains that the fossil record is overwhelmingly composed of isolated teeth, which are small and easy to miss. The trick is to teach your brain to blur out the larger rocks and debris on the ground and focus on the tiny fragments that might be ancient remains. "You gotta tell your brain like what exactly you're looking for," he says. "Your eyes are gonna probably focus on the bigger items on the ground than the smaller ones, but you can train your eyes to blur the bigger ones."

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What you'll learn

1 (00:47) **Introducing the Guest and the Big Question** - Host Flora Lichtman introduces paleoanthropologist Dr. Johannes Haile-Selassie, director of the Institute of Human Origins, and frames the episode around the central question of human origins.
2 (02:14) **Origin Story: From History Student to Fossil Finder** - Dr. Haile-Selassie describes how his first degree in history led him to paleoanthropology through a course on "early man" and a job at the Ministry of Culture in Ethiopia.
3 (03:38) **Life on a Dig: The Reality of Fieldwork** - Dr. Haile-Selassie paints a vivid picture of the physical realities of a fossil expedition in the harsh, 110-degree heat of the Ethiopian rift.
4 (05:49) **The "Treasure Hunt" and the Addictive Nature of the Search** - The host asks about the thrill of the hunt, and Dr. Haile-Selassie describes the emotional highs and lows of fieldwork.
5 (06:48) **The Secret to Finding Fossils: Training Your Eyes on Teeth** - Dr. Haile-Selassie reveals the core skill of a paleoanthropologist: training your eyes to ignore larger rocks and focus on small, isolated teeth.
6 (09:11) **Why Africa? The Geological and Biological Hotspots** - The host asks why certain regions are fossil hotspots, leading to a clear explanation of the underlying causes.
7 (11:09) **The Competitive Culture of Paleoanthropology and Its Modern Shift** - Dr. Haile-Selassie addresses the field's reputation for secrecy and competition, particularly in the late 1900s.

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Show Notes

Where did we come from? How did humanity, with our complicated civilizations and all our human quirks and foibles, come to be? Much of what we know about those questions traces back to important fossil finds in Ethiopia.

Paleoanthropologist Yohannes Haile-Selassie has been key in that hunt for answers. A skilled fossil-finder, he’s helped discover some of the most important known hominid fossils, including the bones used to describe the 2.5-million-year-old Australopithecus garhi, the first pieces of a 4.4-million-year-old partial skeleton of Ardipithecus ramidus, and fossils of the 5.8-million-year-old Ardipithecus kadabba, to name a few.

He joins Host Flora Lichtman to talk about what fieldwork is really like, big questions in human origins, and making the field of paleoanthropology more equitable.

Guest:

Dr. Yohannes Haile-Selassie is the director of the Institute of Human Origins at Arizona State University, and a professor in the School of Human Evolution and Social Change.

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