Interview: Meave Leakey
Pioneering Paleoanthropologist

We've read that you were led to Africa and paleontology because a friend showed you an ad in the newspaper. Can that be true? Was that a turning point in your life?

Meave Leakey: It really was. It's amazing. That was when I was trying to apply for marine zoology jobs. I was getting a bit depressed about it actually. When you have a dream and it doesn't seem to be working out, and you are at that age, you think this is the end of everything.

This friend came to me one day and he said, "There's this very short advert in The Times newspaper. Why don't you just phone?" It was just a couple of lines, saying there's a job in Kenya to work at a primate research center. It didn't say any more than that, and there was a phone number. I decided to phone straightaway, because I was quite excited with the idea of going to Africa and it just seemed to have a lot of potential. By that time, I had realized it was going to be very difficult to get a job in marine zoology, so I was beginning to think, "Okay. If you can't do that, then do something else." And this seemed exciting. I remember on the phone call Louis (Leakey) actually answered the call, and I had, in my excitement, not looked how much change I had in my pocket, and I had all these very small coins and I was frantically feeding this machine with my coins while trying to get the information from Louis. He was basically saying, "Come to London for an interview," and telling me where to go. That interview then resulted in me getting the job and going to Kenya. So yes, it was absolutely the turning point in my life.

When you met the Leakeys for the first time, how soon did you get the feeling that this could be your life's work? Was it love at first sight or did it take a while?

Meave Leakey: When I first went to work at the Primate Research Centre, I was helping run the day-to-day work and overseeing things. At the same time, I was collecting data for my Ph.D. on modern monkey skeletons. There was a good collection of modern monkey skeletons that had been made by the person who was running the research center. Louis Leakey's idea had been that everyone always looks at skulls and teeth to do taxonomy, and he felt that there was as much to learn from the skeleton as there was from the skull and teeth. So he said, "It would be good to do a study to look at the postcranium of the many monkey species that there are in Africa, or at least in East Africa, and to use this collection as a basis to do that." I was really looking at the forearm bones to see how much difference there was between different species, and that was the subject. So I got to know monkey skeletons really well. After I had written up my Ph.D., I heard from Louis again.

Louis asked me to go back and look after the center while the person who was running it left, because she was leaving. She wasn't leaving. Well, she was supposed to leave in January and in the end she didn't leave until June. So I was running it while she was still there but not running it. It was a bit of an awkward time. During that time I met Richard, because when Louis went away he used to ask Richard to take over his projects and things. The first time I met Richard, he called me into his office and told me that the primate center was spending too much money and I'd better take care because there weren't that many funds. So he gave me this long lecture on spending less. I got to know him over the next few months in that capacity. Then he invited me to go to the field with him that year, because they were doing the second year's field work at Lake Turkana. Because of my interest in modern monkeys, it made sense to then start looking at fossil monkeys. So he said, "Why don't you come up and study the fossil monkeys that we're collecting," because they were collecting a lot of monkeys. But he'd only worked there one year, and in that one year had discovered what a fantastic site it was. So that really was the beginning of that long term project, which has now been going for over 30 years.

You mentioned meeting your husband, Richard Leakey. How soon before the two of you became a couple?

Meave Leakey: I met him in early '69. We got married in 1970.

So there was obviously chemistry from the beginning. Besides him yelling at you about the center's expenses.

Meave Leakey: I think so. And he didn't yell. He told me very nicely.

Richard is quite a controversial person and he's very outspoken. Many people don't think he's a very nice person, which is quite wrong actually. He's an incredibly generous, kind, interesting person. So I was always told, "You don't want to meet him. Meet any of the other Leakeys, but not Richard. You don't want to meet him." I never could understand when I did meet him why anyone would have told me that. I guess the people telling me didn't really know him.

What is it about paleontology that seems to bring people together? It seems there are a lot of couples in this work. Does this sort of work form a bond?

Meave Leakey: You do form bonds in the field. I think when one's in difficult situations you tend to form bonds. But at the same time, I think it's because you're a long time in the field. People who are doing different things, it means one person's away a long time, and often out of touch. Even with Richard and I, once Richard left to do other things, keeping in touch with him was quite difficult. Often what he was doing was a little bit dangerous, so it was always, "I wonder if everything is okay in Nairobi," and there was no way of finding out. I think it's very nice to be able to work with your partner in any situation, but I think to be able to do that in the field is very special. So it was great. Before he went off to Wildlife it was really fantastic. Twenty years we had actually working together like that.

Were you aware of the work of Louis and Marie Leakey before you went to Africa?

Meave Leakey: I think anyone who did a zoology course knew their work, but it wasn't something that I ever considered I would be involved in. It was just one of those things everybody knew about, especially because of the publicity in 1959. That was sort of worldwide publicity, so everyone had heard about it.

Could you tell us, briefly, what happened in 1959?

Meave Leakey: In 1959, that was the year that -- they had been working intermittently at Olduvai since -- Louis's first trip was in 1931, and they had gone there together in 1935. So they'd gone back whenever they could find the time and the money. Louis was convinced that if they kept doing that, they would finally find really good evidence of human ancestors there, because the ground at Olduvai is covered in stone tools. There are stone tools everywhere. Louis felt that if they looked long enough, they would find the maker of the tools. It was from 1931 until 1959. In 1959, Mary Leakey spotted these teeth, which turned into a fantastic skull, which they nicknamed -- well, they called Zinjanthropus and nicknamed "dear boy." You can imagine them calling it "dear boy" after all that time. So this was a skull that really set the scene in East Africa, 'cause up until that time there had been no discoveries of anything other than what they had found at Olduvai, which was just isolated teeth and skull fragments.

How old was that skull?

Meave Leakey: It was 1.8 million years, and at the time nobody really knew how old Olduvai was, because they didn't have a date. Olduvai, in fact, was the first site where potassium argon dating was used for an archaeology site. So that date, when it came, was a real surprise, because it was much older than people had thought. That was the setting for research in East Africa.

Your in-laws, Louis and Mary Leakey, what were they like?

Meave Leakey: They were very special people.

My father-in-law, because he died in 1972, I didn't know him that well. I knew him fairly well. The first weekend, when I first arrived in Kenya, he took me down to Olduvai actually that weekend. For two days, he showed me his stuff and he took me to the game park. He had a lot of other visitors he had to show around, so I was able to go with them. Then he took me up to Tigoni, and then after that I didn't see that much of him. Then when I married Richard, Richard and his father weren't on terribly good terms, because I think Louis saw Richard as doing -- because they were working in a similar field and Richard was running the museum. Louis didn't like some of the things Richard was doing, 'cause Richard was trying to bring everything forward. It was a generation problem.

Mary I got to know very well.

I think one of the most fun things I ever did with Mary was when we worked together on her book that she wrote on Africa's Vanishing Art, which was about the art of Tanzania. This rock art, Louis and Mary had recorded in 1953. Mary was very artistic, and she had made all these tracings, and then they had tried to publish them and they couldn't. So instead of publishing them, she had made an exhibit in the museum and then the tracings had got left in the archaeology lab. Richard had raised money to build a new building for the pre-history. So when we moved all the archaeology from the archaeology lab to the pre-history building, I came across all these tracings. I said to Richard, "It's terrible. These things really should be published because they're so fantastic." So he found a publisher, and Mary said if I would help her then she would spend some time to do it. So we worked together on this book, and it was a really good time, because she had a fantastic command of English. It was very interesting, seeing the way she wrote, and how everything had to be absolutely exact and right. She obviously loved her time in Tanzania, doing that work. Especially because she was so artistic. So it was very special, and I really got to know her well then.

She was a great influence on me. If you did science, you did it absolutely exactly, and no corners cut, no fuzziness. She was very disciplined in her science. That was something that brushed off on me, that this is how it has to be done. If you talk to any of the field crew who worked with her, there are many stories. She absolutely couldn't stand bad work. If somebody was digging something up in what she considered to be a bad way, she'd say, "You're not digging your loshanda (garden). You're not digging up potatoes. Do this properly." She was really quite strict, even with them. She was just a fantastic character and she never minced her words on anything. She said exactly what she felt.

It sounds like an amazing experience to have worked with her.

Meave Leakey: She was a wonderful woman.

What makes the Turkana area so rich with these ancient fossils? Why there?

Meave Leakey: If you look at a map of Kenya, and you impose on it all the archaeological pre-history sites, they're all down the Rift Valley. The Rift Valley goes right through the middle of Kenya. Lake Turkana is the biggest lake in the Rift Valley, in Kenya, and it's a huge lake basin. The rift is important because it was formed as a slight depression that got deeper, and water drained into the depression, taking with it sediment, and the sediment buried any evidence of life or archaeology or whatever. So that was then buried and preserved. Because the rift is still forming, and erosion is still taking place, things that were buried four million years ago or three million years ago are now being exposed in some places. The whole process is one of continuity. There are still things being buried and still things being exposed. So that's why all the sites are down the Rift Valley, and the Turkana Basin has been a sedimentary basin since -- the formation of the Turkana Basin has been well over four million years. So there's a relatively continuous sequence that goes from four million years up until present time, and it covers exceptionally well the time of the emergence of Homo and Homo erectus and that time interval.

This is how long ago?

Meave Leakey: Two million years and less. That's on the east side of the lake. In other areas of the basin it goes back to as much as four million. So there's a really very good record of that whole time interval from four million years until Homo sapiens appears. So it's just a fantastic record.

We've read that this area was particularly rich in hominid fossils, especially in the first years.

Meave Leakey: Yes...

Those early years were really exceptional. We didn't, I don't think, at the time, appreciate really how lucky we were. Because we were going into this huge site that nobody else had worked, so nobody had been in there looking for fossils. So everywhere you went, there were the most incredible fossils and many of them were specimens of our ancestors. So you know, we were finding sometimes more than one a week, and if we didn't find one a week, we felt we were doing pretty badly. Now it's quite different. Now you really have to look, but the evidence is still there. There's still an enormous amount of work to be done there. It's just a really incredible site and I think it would be difficult to find another site to match it in Africa at the moment. And added to that, because we've been working there now on the east side since 1968, the east and west side, and the Omo Valley was actually worked before that. So there's a record that people have been working there for decades now, and so (we have) that basic data and basic understanding of the lake's history. We now know where the sites are, how old the sites are, and if you want to answer a particular question, which the best sites are. Now we're going over sites that we worked 20 years ago or more and finding more things have eroded out. But we go there knowing the background of the site. We know the background of the evolution of the animals, of the humans, of the environments, and so we have a good context to put everything in now. So it's really very special.

You made an extraordinary discovery in 1994. Could you tell us about that?

Meave Leakey: At the time, the earliest fossil of human ancestor that was known was Australopithecus afarensis, better known as Lucy, that Don Johanson had found in Ethiopia. And Mary Leakey's footprints, which were found in Tanzania. That was the earliest evidence of bipedality, people walking on two legs, and of human ancestors. The theory was that this was the common ancestor of everything that came afterwards. But...

We knew from molecular evidence that apes and humans split around about five or six million or maybe even earlier. And it seemed odd that there was no diversity, nothing really much going on in that time. We felt that it was more likely to be due to lack of evidence than the reality of the situation. So what I wanted to find out was "What went on before afarensis? What happened before Lucy? Who is Lucy's ancestor?" We thought that 4.1 million was the perfect age, because it was pre-Lucy. What we found there was a number of -- not complete skulls -- but parts of jaws, and also a leg bone. The leg bone showed clearly that at 4.1 our ancestors were walking bipedally, so it took back the evidence of bipedality. It also showed that the things we were finding were more primitive, more ape-like in many ways, to afarensis. So it really took back the record earlier, and made a very good ancestor for Australopithecus afarensis, in fact. So it didn't show there was any diversity in the earlier time, but it did show that you could take the record back. Since then, of course, there have been more staggering specimens discovered, going back towards six million.

A later discovery of yours created quite a stir, didn't it?

Meave Leakey: That was in 2001.

Once we had worked the site at 4.1 million, which is called Kanapoi, we decided that we could work at a site that was the same age as Lucy and see if we could find afarensis, or whether we'd find something else. Because again, I was still thinking that there should have been diversity at that time, and it shouldn't just be the common ancestor there, but it should go back further. So that's why we were working at that age, 'cause it was the same age as the sites from which Lucy came. What we found there was a skull, and other specimens as well. But we only named the skull because we couldn't relate the other specimens directly to the skull. But the skull had a very flat face and a very long face. Lucy's face is much more protruding and much more ape-like in many ways, actually. The face shape showed that the species was not afarensis, it was something different. So it showed that there were at least two hominid species living at the same time as Lucy. So therefore, Lucy wasn't necessarily the common ancestor. It could have been the species that we found, that we called Kenyanthropus platyops, or it can be something else that we haven't yet found. I believe sincerely that in the end, there will be several different things found at that time as there are later.

So this was not just a new species, but a new genus?

Meave Leakey: We note a new genus and species because it just didn't fit into any of the genera that were known. It may in the end prove that you can fit it into another genus, but for the moment it made more sense to call it a new genus. You didn't know, if you're going to put it in another genus, whether it was better to put it in any of the known ones. It just didn't fit.

When you found this skull, Kenyanthropus platyops, what was that experience like? What did it look like? Did you know immediately that it was something extraordinary?

Meave Leakey: It was in the ground in situ, but it was very cracked and broken, and it had roots going through it and it was covered in rock. It actually took one of the preparators in the museum, Christopher Chiari, nine months to get the rock off the skull, so it was nine months before we could really look at it and see what we had. So from the time of digging it out of the ground, we had to wait nine months before we could study it and then when we studied it we had to compare it with all sorts of other things. So that's why it wasn't actually published until 2001, in spite of being found in 1999.

How soon did you realize this was something very important?

Meave Leakey: Well, the first thing we did was take a cast up to Ethiopia and look at all the afarensis things. That was the main thing we wanted to check, first and foremost, was whether it was the same as Lucy and whether it was Australopithecus afarensis. I think after we had done that, we had a feeling that we probably had something different. We then went down to South Africa and did the same thing down there, and through the entire study we were building up the evidence and we were saying, "We won't actually make any deductions yet. We'll do the whole study and do the whole comparison." We made a big database of all the measurements. And then we could see how far out of the range of other things our measurements were, and which features come outside the range and which features come in, and then we can assess whether we really have something. A different species? The same species or something else? Or a different genus and species, or whatever it is. Having done that, that was the conclusion we came to. It made more sense to make it a new genus and species than just to make it a new species or to put it in anything that was known.

So it's really a matter of looking at the variation of other things and just seeing where it fits, but this particular specimen has very small teeth compared to anything else. It has this very flat face and very deep face. And there are a number of measurements that you can take that just fall out of the known range of other species, which is how you decide what you have.

Not everyone accepted your revolutionary discovery. In Scientific American, Tim White of U.C. Berkeley was quoted saying, "It's just a variant of afarensis. It's not a new genus."

Meave Leakey: That's right. Tim doesn't believe in diversity before afarensis at all. He sees everything as a straight line. That's how people saw the whole of human evolution, but it simply doesn't make any sense to me. There's no other animal that would evolve in a straight line for six million years or even for three million years. It makes much more sense to have diversity earlier in time. What he's saying is that at the moment we don't have any good evidence that there is that diversity, because he doesn't accept platyops. He says it's too distorted. Where we see a flat face, he says that's due to the distortion rather than anything else. I find it hard to make that distortion come to a flat face. It is distorted because it has got these many, many cracks in it, but I don't think that distortion causes a flattening of the face to that extent. Most other colleagues agree with us. Very few others actually take Tim's line, but I think it's good to have difference of opinion. That's really how science progresses. If you have differences of opinion it stimulates others to do more research and come up with an answer in the end. It's not a bad thing at all. It's a very good thing. Hopefully, sooner rather than later, we'll find another specimen that will prove the point one way or the other.

How did you first become interested in science and exploration? We understand you were strongly attracted to nature as a child in England. Could you tell us about that?

Meave Leakey: I guess that's where it all started really. I don't remember much about it. I remember a little, but my mother tells me...

I was always collecting insects and caterpillars and this and that. We had a very small cottage because it was the war years, so my father was away in the war. We were living in a small cottage in Kent with woods all around it. So I used to go out and collect all these little insects and things like that. I really loved nature even in those days. My mother said -- we had a little porch and the porch was full of jars of things that I used to feed everyday -- she had a number of stories of how I kept little furry caterpillars. I used to keep them on a matchstick and go to bed with them and then they'd get out in the night and there were furry caterpillars all over the bed. But I don't remember too much about it. I just remember vague things. I think the memories --you never know how much you remember and how much you've been told and you put things together. But I think, really, in those days I was interested. Then, my father was very interested in natural history, and as a child he had always done that sort of thing. He used to take a lot of photographs, so he taught me how to develop and print photographs when I got older. He had all these wonderful pictures of wildlife and birds, and snakes and lizards, and all sorts of things. I remember just loving spending time with him in the workshop and in the dark room. And learning how, and seeing all his photographs that he hadn't really looked at for years and years.

What kind of work did your father do?

Meave Leakey: He was a surgeon, an orthopedic surgeon. So he was working with bones, too. Another link!

You say your family had moved because of the war. Did that affect your schooling as well?

Meave Leakey: I think I was too young then. I was born in 1942, so by the time I was going to school the war was over. But I do remember in those early years there was no sugar, no sweets and no eggs, and no this or that. When these things gradually came back it was such a treat, these things that modern children take for granted.

Did your parents foster your love of nature?

Meave Leakey: Oh, very much so, particularly my father, I think. It was a shared love really. We used to have holidays down by the sea in Cornwall. Grubbing around in rock pools on the beach and things was another way that we shared that interest. Both my parents were very much country people, although he was always in the city, so my initial years, after the war years, I was actually living in a suburb of London.

Did you have brothers and sisters?

Meave Leakey: Yes, but my sister is four years younger than me, and my brother is nine years younger than me. So they were quite spaced out. We weren't all born together and growing up together. By the time that my brother was going to school I was in boarding school. My brother, in particular, I didn't get to know that well as a child.

What did they become? What do they do?

Meave Leakey: My brother became a geologist. He did some general geology, and then he worked for a firm, looking at geology to see the structure for buildings. My sister was also interested in natural history. She did her M.Sc. in Uganda actually, on a funny little animal called a potto. I don't know if you know what a potto is. It's a primate. It's a prosimian. It's related closely to the bush baby but it's very slow. You can't believe how slow it is when it moves. It's nocturnal, so poor Jeannie, my sister, was up all night watching this thing moving so slowly. But she was studying behavior of pottos for her M.Sc. and then eventually she went into teaching.

She must have been very patient.

Meave Leakey: I think so. I think it would have sent me to sleep.

What kind of student were you? What kind of school did you go to?

Meave Leakey: Initially I went to a convent as a day care, and then eventually my parents sent me to a girls' boarding school. It was a good school, but they didn't teach girls science. In those days, girls didn't really need to learn science it was thought. I don't think my parents realized this. When I finally took my A levels, they started saying, "What do you want to do before you take your A levels?"

How old are you when you take your A levels?

Meave Leakey: It's 16 or 17. And then, in the English system, you do another two years, and then you're qualified to go to university. So you chose your A levels depending on what subjects you wanted to do at university, depending on what career you wanted to choose. So you are really in a way having to choose whether you do science or arts at 16 and 17. I definitely knew I wanted to do science. There was no question. Because we hadn't done science at school, there was no way that I could qualify to go to university so I had to go to a technical college and do science O levels and then science A levels. Then I was qualified to go to university. So I had to sort of redo all that.

That was a long time to be in school.

Meave Leakey: It was. It was a technical college near our home. I sort of crammed it anyway.

In some medical schools there are more women than men nowadays. When you look back, it was really just a generation ago that women were not regarded as potential scientists.

Meave Leakey: Things have really changed, and dramatically changed I think. It's really encouraging now when I'm talking to students, in America particularly, that the student body is often more girls than men, young women than men. And it is, as you say, it's very quick. It's happened really quickly. I really wanted to do marine zoology, so I chose my university because there was a very good marine station there. I never dreamt I would be anything but a marine zoologist. It was straightforward as far as I could see. I went to a good school, got a good degree, and there you go. But when I started to apply for jobs, the answer was always negative, because I was a woman and they didn't have facilities (for women) on boats for men. You really can't do oceanography and marine zoology without going to sea. So it was just "No, no, no." Which is how I finally got into going to Africa and doing paleontology.

Was there any teacher who believed in you and encouraged you and stands out in your memory?

Meave Leakey: At university definitely, because I was the only student doing an honors degree who was doing marine zoology. So there were people there who really encouraged me. I was very fortunate, because I was able to join the M.Sc. (Master of Science) course and attend all their lectures, which was just great.

I was with the Master's students, although I was just doing a regular honors degree. So I was getting more information than I would have got if I had been with another club. But in the zoology, we had an excellent functional zoologist who did the evolution course. Looking back on it that was actually -- I was very focused on the marine, but that evolution course was really one I enjoyed enormously. He was an excellent lecturer, and he was very, very succinct in what he said, so it was always very clear and very easy to understand, and always made so much sense. I really enjoyed his course a lot and he was very enthusiastic and very encouraging.

What was his name?

Meave Leakey: Lew Alexander. He has gone on to do a lot of functional work.

What would you have done had you become a marine zoologist? You've described the setting at your university as being particularly attractive to somebody in that field.

Meave Leakey: I don't know. I mean, in those days I was already concerned about climates. That was something that always interested me and there was a lot in the oceans that you could find out about climate. I think that connection was of interest. But I also liked marine zoology and the animals. The thing that always has intrigued me is going deep, the sort of work that Sylvia Earle does. I always think that if I hadn't done what I've done, to do what she did would have been fantastic.

Do you scuba dive?

Meave Leakey: Yes, but I'm not very good.

What about books when you were a kid? Were there books that were particularly important to you as a child?

Meave Leakey: I don't recall any more than any others. I think I sort of read what everybody else was reading. I just read everything I could get my hands on.

When you decided to go to school for marine zoology, what kind of reaction did you get from your parents? Were they supportive?

Meave Leakey: They were very supportive. There was no problem there at all. All parents want their children to do what they enjoy doing and they want them to do something that they can really get some professional satisfaction out of doing. I'm incredibly lucky to have done what I've done. I've really enjoyed every minute of it.

Did your mother work?

Meave Leakey: She used to work at home mostly, doing insurance cases for my father, because there was a lot of sort of home secretarial work that needed doing. Writing out reports and things. So she didn't go out to work.

Did she live to see some of your own achievement?

Meave Leakey: No, unfortunately, she didn't. She died while I was first in Kenya, before I had finished my Ph.D., a long time ago.

And your dad?

Meave Leakey: He died quite recently. So yes, he came out very often to see us and see what we were doing and he took a great interest in it.

I can imagine he must have been fairly thrilled to see that.

Meave Leakey: Yes. That's right. Yes, he was. He was always interested.

Do you ever wonder what would have happened if your friend hadn't seen that ad in the newspaper?

Meave Leakey: Had he not seen that advert, that's right, I would have done something else. Absolutely.

Obviously you were drawn to the idea of it. Were you in London at this time?

Meave Leakey: No, I was living in Kent. I was still at university, because that was before I finished my course. You know, you are always applying for jobs before you actually finish the course and before you take your exams, because you want to know. In those days The Times was one of the main papers. There were many less papers then. They had a page full of adverts on the front and then it switched to the back or the other way around, and they were strange adverts some of them. They were just advertising all sorts of things. Now the pages of adverts in the newspaper are so many, but then it was just one page for private adverts.

Didn't it take a lot of courage to just go off and move to Africa suddenly?

Meave Leakey: I think at that age one gets very excited. People didn't travel so much in those days, and the thought of going to Africa was really exciting. I suppose in a way it takes courage, because you're leaving everything behind that's familiar, but at the same time one is really excited by having the chance to do that.

How old were you when you went for the first time?

Meave Leakey: I was born in 1942 and this was in 1965. So 23, 22.

It's amazing how one little twist of fate can change your life.

Meave Leakey: It's extraordinary. You can grow up thinking you're going to do one thing, and then you end up doing something that you never even thought about really or never dreamt you would see. It's extraordinary.

Would you say you have to leave yourself open to other possibilities?

Meave Leakey: Absolutely, yes. If you're determined to do something, that's also good. But it gets to a point where there's no point trying to hope that you can do something that you are obviously not destined to do.

What challenges do you look forward to? What other mysteries do you hope to pursue in the future?

Meave Leakey: Right now we're working at the more recent end. We've gone up to the Homo erectus times. We're now working between 1.5 and just over 2 million years ago.

Not quite yesterday.

Meave Leakey: Well, it's getting closer to yesterday.

We're looking at the time of the emergence of the genus Homo and the emergence of Homo erectus, which is a time where there's a lot of evidence that's been found. A lot of all those things that we were finding in the '70s and '80s really fit into that time. But there's many, many questions. I think the more specimens you have, the more questions there are to answer. So there's many, many questions related to "Why does Homo erectus move out of Africa when no other species had done that? Why did the brain start to expand? What made Homo? Why did our ancestors start making stone tools? What was the environmental stimulus for all these things to happen?" So that we're looking at those sort of questions.

Ultimately, what anyone working in the field wants is something that gives you the maximum amount of information. Nothing gives you more information than a skeleton with a skull, but it's the most difficult thing to find. Anything that can give you information that will answer a particular question is important. But if you have a complete skull and mandible and a face, you're going to have much more information than if you just have a mandible, or you just have the back of a skull, or you just have the face. You're looking for the most complete things you can find. Personally, I think the postcranial -- the skeleton -- is really going to help with taxonomic problems. If we had some good skeletal material we could begin to sort out all those different species, and what they're doing, and why they're all there at once. Those sort of questions.

Your discoveries have had a lot of implications. There was an understanding that human evolution proceeded in a straight line, from one species, to the next, to us. You've sort of turned that on its head, haven't you?

Meave Leakey: Well, we didn't turn that on its head. All the work in East Africa has turned it on its head gradually. That began at Olduvai, because Louis and Mary found different species contemporaneously at Olduvai. We just added more specimens that enforce that view.

For me, the most important message that comes out of this whole study is that we have a common origin and we are one species. That common origin is really important, because there's so many prejudices in today's world. There are so many divisions, cultural divisions, but they're all skin deep. Even our skin color doesn't mean anything in terms of evolution. It just means that our closest ancestors were living in a different latitude from people with dark skins, people with pale skins. It just determines which latitude your recent ancestors lived in. So I think to remember that we're one species, with one common ancestor, is a very unifying theme. Anything that helps reduce prejudices, and makes people realize that different cultures and different traditions are just things that enrich our lives, rather than things to be the cause of wars and conflicts and things, is important.

One of your daughters is also involved in paeloanthropology now, isn't she?

Meave Leakey: One daughter, yes. My oldest daughter, Louise, is now working with me, so we're working together, which is really nice. She flies a plane and is very good at organizing things, so she's basically in the driving seat now and she does all the logistics and organization of the field work.

What about your other daughter?

Meave Leakey: She's working at the World Bank. She got more into development and economics and that sort of thing. I think they both wanted to do something for Kenya and I think Samira felt that development and economics would be one way that she could actually do something like that. At the moment she's working in Washington, D.C., with the World Bank.

For a young person who doesn't know about your field, how would you describe what makes it so exciting?

Meave Leakey: I think it's the same for any science. We're just doing another sort of science.

All scientists are driven by this enormous curiosity. They want to know why something does this, or why something looks like that, or how something works. Every scientist is just driven by this enormous curiosity to find the answer to some question. It's the same with us. We're wandering around in the desert, in the wind and the sun and the heat, and we know if we look hard enough, we're going to find a fossil that will tell us something we didn't know before. It's incredibly obsessive really. You just know if you keep at it, you know you're going to get the answer. The frustration is that you can't do it all the time, because you have to take breaks, and you have to write up, and you have to raise money and all this sort of thing. So I think that, for anyone going into science, whatever branch of science, they have that same curiosity that drives them.

Thank you. It has been wonderful talking with you.

Meave Leakey: Thank you.