'Deep inside, something told me I had found the earliest human ancestor. I went numb.'

Yohannes Haile-Selassie on his lifetime quest to discover ancient humanity.

Fifty years ago, the discovery of a partial skeleton amid the barren desert landscape of northern Ethiopia transformed our understanding of where humans came from, and how we developed into Homo sapiens.

“Lucy” was first spotted on November 24 1974 by the American paleoanthropologist Donald Johanson and his student assistant Tom Gray. Named after the Beatles’ Lucy in the Sky with Diamonds, a popular song in the their team’s camp at the time, it was immediately clear she was a female, because of her small adult size, and that she had walked upright, unlike chimpanzees.

Lucy was also very old – at almost 3.2 million years, she was anointed as the then-earliest known (distant) ancestor of modern humans. Over the following decades, rather fittingly given her name, she became a “paleo-rock star”, going on a US tour from 2006 following a deal with the Ethiopian authorities.

Lucy’s discovery marked a critical moment in our understanding of the origins of humanity – and of Ethiopia’s place at the heart of this story. Many other important fossils have since been discovered in the same Afar region – including by Yohannes Haile-Selassie, one of Ethiopia’s leading paleoanthropologists and the director of the Institute of Human Origins at Arizona State University (ASU) in the US. His two Ardipithecus discoveries in the 1990s – while still a student – pushed understanding of our ancient origins back beyond 5 million years, changing some of the widely accepted beliefs about human evolution.

Yet in this Insights interview, Haile-Selassie is critical that the study of ancient humans still fails to acknowledge and support the fundamental role of African scientists and institutions. Like many of his colleagues, he is now calling for paleoanthropology to be “decolonised”, warning that otherwise, some African countries could take action to restrict future exploration of key sites across the continent:

There has to be a mutually beneficial way of doing things from now on. Western scientists can’t continue this ‘helicoptering in and out’ approach to fossil discovery. A lot of African countries have realised this and, unless we act fast, they’re probably going to tighten up who should be allowed to do research in their countries.

Yohannes, you were a 14-year-old schoolboy in Ethiopia when Lucy was discovered. What are your memories of this landmark moment in your country’s history?

In fact, on the day Lucy was found – Sunday, November 24 1974 – Ethiopians woke up to some other devastating news. The previous night, Ethiopia’s military regime had executed more than 60 ministers and generals of Emperor Haile-Selassie’s regime. The announcement of Lucy’s discovery probably came up later that week, but I doubt many people paid attention to it amid all the turmoil, with the military regime taking control of Ethiopia.

Personally, I have no recollection of the announcement of Lucy’s discovery. I grew up in a Christian family, so as far as I knew at that time, it was God who created humans and I wouldn’t have understood the significance of Lucy.

Of course, over time, her discovery brought the idea of Ethiopia as a “cradle of mankind” to the forefront of public consciousness around the world. With that came national pride – today, Ethiopia brands itself the “land of origins”. Lucy played a big part in that.

Yet even now, the narrative of ancient human discovery appears to omit many of the African researchers and institutions that played key roles in this story?

Many of the fossils that made western scientists famous were actually found by local Africans, who were only acknowledged at the end of a scientific publication. For a long time, African scholars were never part of telling the human story; nor could they actively participate in the analysis of the fossils they found. Up to the 1990s, long after Lucy was found, we were only present in the form of labourers and fossil hunters.

So, when we celebrate the 50th anniversary of Lucy, we shouldn’t forget that a reappraisal of the role of African scientists in our understanding of ancient humans is long overdue. Specifically, we need to decolonise paleoanthropology.

What does that mean in practice?

Without the proper infrastructure, African countries are going to be stuck in the same old cycle where they are expected to facilitate western scientists’ research – with institutions getting some income from laboratory service fees, and some locals being paid field per diems, but that’s about it. If you ask anyone who works in Kenya, Tanzania, Ethiopia or South Africa, they will tell you things have to change, particularly in terms of local scholar training and involvement in the actual research. That’s why this movement of decolonising palaeontology is becoming really vibrant now.

We need a firm foundation established, so the next generation of African scientists doesn’t have to deal with issues, like lack of infrastructure, that we faced. This requires a change in terms of how we think about paleoanthropology – and how we think about Africa in general. African institutions don’t have the resources or trained manpower to develop programs like this – and most African countries have a lot of pressing social, political and economic concerns, so paleoanthropology is not going to be their highest priority.

But, if they are interested in seeing more of their scholars involved in this field, they need to build the necessary infrastructure so that foreign researchers can help with programming and training. Scientists cannot build laboratories, but they can help with what goes to those laboratories and help develop training programs.

To what extent is your own success in breaking down the ‘glass wall’ of ancient human exploration a result of your most famous fossil discoveries?

I’ve found so many important fossils in the Middle Awash [a key research area in the Afar region] that I can’t exactly say one is more important than the other. But the first one that really made an impact was “Ardi” (from the full species name Ardipithecus ramidus) in 1994, which I found when I was still a graduate student at the University of California at Berkeley. Just as Lucy resulted in a major paradigm shift 50 years ago, Ardi again transformed the way we think about human origins.

The first piece I spotted was a finger bone, but in time we found Ardi’s near-complete skeleton. Another female, she had complete hands, feet and more skull bones that were missing from Lucy. She was dated at 4.4 million years old – 1.2 million years older than Lucy, and an entirely new genus of a hominin, Ardipithecus, that looked unlike anything that had been found before.

Three years later, you discovered an even older hominin fossil in the same area …

Once you get used to finding good fossils, you don’t tend to get as excited when you find another. But there’s one discovery I will never forget – the extraordinary feeling when I found the partial jaw of Ardipithecus kadabba in December 1997, a species I went on to name four years later.

Part of the jaw was just lying there on the surface. And deep inside, something immediately told me I had found the earliest human ancestor – more than 5 million years old. The thought made me go numb for a few seconds – I’ve never had that kind of feeling again. Literally no hominin fossils from that age had ever been discovered before.

The first thing I did was stand up and look 360 degrees around me, to check I wasn’t at one of the other, younger geological parts of the Middle Awash. My Ethiopian compatriot, Giday WoldeGabriel, and I had been surveying this new area for a few years. I was still looking for a topic for my dissertation – my advisor had told me: “Go look for fossils in the older deposits [more than 5 million years old], find as many as you can, and describe them.”

I’m trained as an osteology student, so I can easily distinguish fragments of an ancient human skeleton from other fossils. And the jaw still had one tooth on it – so it was really easy for me to identify. After that, we surface-scraped and found a lot more teeth from the same jaw. Everybody was so excited.

What happens when you find such a special fossil?

The first thing you do is go out and look for more. The next day, we went back to another little patch and found a fragment of arm bone from a different individual. And for the next three days, wherever we went, we found a tooth, a fragment of arm bone, or something. We’d been looking for early human ancestors in this area for so many years – and now all of a sudden, we were finding one piece almost every single day.

During survey and exploration, we were sometimes staying in a “fly camp” for days – just a few tents, some water, and basic food like spaghetti and bread. While in the camp, we washed the fossils then packed them up to take back to the laboratory in Addis Ababa. Until that stage, the fossils are totally under your control and you can look at them every day, show them to whoever you want and let them touch the fossils. But once the fossils were back in the national museum, access would be limited to you and your collaborators – the curators are the custodians from then on.

What’s the secret of being a successful fossil hunter?

There is no magic formula. You don’t learn it in classrooms. It’s all about how you train yourself and your eyes to focus on smaller objects when you are in the field. Of course, knowing skeletal elements and what they look like helps – but most importantly, you must be able to distinguish a fossil bone from a rock, or something else that might look like a fossil.

Most of the most important early human ancestor fossils found in Ethiopia, Kenya and Tanzania were found by our local collaborators who don’t have a degree, or may not even have been to school at all. This means there are many great fossil hunters who make significant discoveries but aren’t involved in their scientific interpretation; and then there are some paleoanthropologists who are not such good fossil hunters but great in interpreting the fossil evidence.

You don’t have to have a degree to be a good fossil hunter. But finding good fossils is sometimes a matter of luck as well.

And sometimes it can be very dangerous …

The Afar region is mostly dry desert – so one of the major challenges is the risk of getting caught up in a conflict between two of the local clans of nomadic pastoralists, if they are fighting over water or grazing land. When you’re caught between two different clans clashing, that’s the worst time. This has been going on for hundreds of years, and it can be really risky. You could be shot at by people who are just feeling suspicious of your presence there.

I mean, you’re going into somebody else’s territory – people who have lived there for millennia. For the clans, it’s about water and grazing. As long as you don’t interfere with that, they’re fine. Their culture is very different from ours, but we respect it as much as we respect our own.

We try to hire as many of them as we can, depending on our needs and budget. We hire the same people for a long time and eventually, we become like family – that’s how we’ve been doing the work for decades, going back again and again, finding all these great fossils. Most of the time it works really well and when we leave for the field season, they can’t wait until we come back the next year. This may not be the case everywhere though.

Is climate change making it harder to work in these areas?

It’s a desert area, so the water resource has always been limited. There’s one river that flows all year round, and it’s the only water we all have access to. But climate change is resulting in less grass for the animals to graze on, so the people we work with sometimes move farther away from their usual area looking for grazing land – and sometimes that gets them into conflict with other clans. Some years, we don’t see a good number of our usual workers because they went somewhere else with their animals.

This is nothing new – it’s been happening for many, many centuries. But climate change is altering a lot of things on the landscape, and increasing the risk of deadly conflicts as different clans try to access limited resources.

Is there a reason why so many ancient humans have been found in a relatively small part of Ethiopia?

The Afar desert in Ethiopia was not a desert in the deep past. It was a place where life, including some of our earliest ancestors, flourished for millions of years. But the fact this area is located in a tectonically active region with three of Earth’s plates slowly pulling apart, creating a deep rift valley between them – the rifting has facilitated the past life history of the area to resurface in the form of fossils. In that sense, the region is geologically unique and not seen anywhere else in the world.

So, we cannot conclusively say these early human ancestors whose fossils we are finding in the East African Rift valley never lived anywhere else. The problem is we don’t have, or haven’t yet found, many ancient sediments of equivalent age outside eastern Africa where we can look for fossils of ancient human ancestors.

There are some very important exposed sediments outside the East African Rift system – for example in Chad in Central Africa, where the very earliest hominin fossils have been found, dating back between 6 and 7 million years. But a much wider geographic distribution of early human ancestors, at least within the tropics, cannot be ruled out. That is why continued survey and exploration outside the known sites in East and South Africa is of paramount importance.

Are there specific new areas that scientists should be looking?

There are so many areas in Africa that haven’t yet been explored but need to be. You haven’t heard anything about hominin fossils from West Africa, right? But now, people are thinking about exploring that region in search of human ancestors.

The story of human origins is not like the law of gravity – once figured out and done. New fossil discoveries will always help us understand it better. And there are some questions we cannot answer until we find more fossils and larger sample size from even deeper time – such as identifying the common ancestor humans shared with chimpanzees some 8 million years ago. What would it look like? How did it move about?

Meanwhile, the science of studying existing hominin fossils is getting better all the time, aided by prevailing technology…

We’ve collected hundreds if not thousands of early human ancestors over the last 50 years since Lucy was discovered. When she was found in 1974, all we could study was what was visible on the external surface of her bones – taking measurements and so on. But now, we have the technology to scan her skeleton and look at the internal structure of the bones.

So, even if we don’t have any new fossils emerging, those we already have in our museums and laboratories will keep generating a lot of knowledge because we’re improving the technology; the way we analyse the fossils.

Are there any important specimens found in Ethiopia that have still not been returned?

In the old days, the reason western scientists took them out of Ethiopia was because the country had no laboratory to study them in. Or at least, that was a good excuse. But once Ethiopia had a laboratory, they had to go back. The laboratory at that time wasn’t big enough, but it was a good start. And the one we have now, in the National Museum of Ethiopia in Addis Ababa, is a state-of-the-art, four-storey building in which we can keep and study all of the fossils from anywhere in Ethiopia – including Lucy.

In the old days, another excuse was: you don’t even have enough space to store them if we return them, right? “No, we do” was the response – so the message even in the late 1980s was just send our fossils back. All of the Ethiopian hominins are back in Ethiopia now, in part because of the tough stance the government took when it invoked its moratorium on fossil exploration between 1982 and 1989. All of a sudden, the government said: “No permits. We’re stopping exploration until we can get a new antiquities law, and ensure more control over our own cultural heritage, including ancient human fossils.”

Are you optimistic about the future of paleoscience in Ethiopia?

The fieldwork is not going to stop even after we are done. There is a new generation of scientists – including many from Ethiopia, I hope – who are going to continue our work. But their approach, their methodology, their “search engine” is all going to look very different, and hopefully much better, from the way we did it.

But as the fossil evidence continues to come out of Africa, we have to also be able to conduct the research in the countries where those fossils are being found. Our efforts to better understand the human story cannot be dominated, like the old days, by western researchers shuttling in and out, without community engagement or leaving any meaningful impact on the countries yielding all these fossils.

African institutions with paleoanthropological resources need external help, and it’s only fair that western researchers with resources help these institutions as much as they can. Honestly, it’s for their own good too. But it is up to each country in Africa to identify what support it needs. Everything is in their hands. If they say: “If you don’t help us with this, we’re not going to let you do research,” then that’s it, it’ll stop. So, we have to make sure we don’t get to that stage.

Is ‘brain drain’ a big worry for you?

Definitely. I can give you one example: myself – I live in the US and work at ASU. At the time, there were few other options for me. But even today, African students come out to the US for training and often don’t go back to their own country. To reduce brain drain, we need more paleoanthropology programs in African universities and other local institutions to counteract this tradition. No one would want to leave their homeland if they had the same opportunities they long for abroad.

I’ve been asked how come there are no trained scholars from the areas where these fossils are actually coming from, such as the Afar region. I didn’t have an immediate answer to that – but since then, the lack of a paleoanthropology program in that region, where Lucy and so many fossils have been discovered, has become a real concern to me. Now, I’m trying to build a collaboration between ASU and Samara University, so we can start a paleoanthropology masters program there. I hope many of my colleagues working in the Afar region will help me on this.

This is where online teaching becomes really important as well, so that African students don’t have to move abroad in the first place to get their education. ASU has been renowned for its online teaching even before COVID sped it up – it’s a pioneer. And that’s another means that we have to help African universities develop new programs by collaborating with western universities like ASU.

I am deeply interested in helping develop paleoanthropology programs in Ethiopia and elsewhere, because we need to increase the number of local African scholars who can actively and meaningfully participate in telling what is perhaps the most important story of all: where did humans come from, and how did we get here?

Disclosure statement: Yohannes Haile-Selassie does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

The Conversation has a distinctive model where we get over half of our readership by sharing our journalism with other media outlets. We get a byline, and we get to reach many more people – and thousands of websites and print publications benefit by getting fact-based, well-edited, interesting articles to bring to their readers.