Wednesday, December 2

Meave Leakey: ‘Africa is definitely where it all started’ | Sciences


For more than 50 years, Born in Great Britain paleoanthropologist Meave leakey has been unearthing fossils of our earliest ancestors in Kenya Turkana Basin. His discoveries have changed the way we think about our origins. Rather than an orderly progression from ape to human, his work suggests different prehuman species living simultaneously. Leakey’s new memoirs, The sediments of time: my search for the past throughout my life, co-written with his daughter Samira, reflects on his life in science and reconstructs what we now understand about the evolution of our species driven by climate.

Leakey is part of a famous family of paleoanthropologists. Her husband, Richard Leakey and her parents, Luis and Maria, are known for their discoveries of the first hominids.

Meave, 78, is teacher in Stony Brook University, New York and director of field research at the noprofit Turkana Basin Institute, a collaboration between the Leakey family and Stony Brook.

You graduated in the 1960s with a degree in zoology and marine zoology from the University of Bangor and envisioned a career as a marine biologist. How did you finish fossil hunting in Africa?
I had written to many marine centers around the world and got the same response: they had no facilities for a woman on a ship. Fed up, I decided I would have to try something else. A boyfriend at the time found an ad on the back cover of the Times for a research position at the Tigoni Primate Research Center in Kenya. I called the number and Louis Leakey answered. Within a few weeks he was on the plane.

I met Richard when he was running the center. I had just gotten my doctorate in zoology, studying monkey skeletons. Richard contacted me to tell me that the center was spending too much money and that we needed to save. We got along well and I started to see him quite a bit. He asked me if I would like to work with him on his fossil site. This is how I got to Turkana and then to the fossils.

You and Richard were married in 1970 and your daughters, Louise and Samira, were born in 1972 and 1974.. How did you balance research and motherhood?
I didn’t want to miss out on the excitement of the fieldwork, so both boys were brought to Turkana within weeks of their birth. They would stay at base camp with someone to watch over them while we went to work. As they got older, they hung out with us from time to time.

There is one skull in particular that remains one of my favorite fossils, due to the happy memories I have of rebuilding it, with a baby hippo playing in the lake and baby Louise playing at my feet in a basin of cool water. It was a really special moment.

In the late 1980s, Richard headed Kenya Wildlife Service and you took over the direction of the field work. In 1999 his team found the skull of an early hominid that was roughly the same age as the famous Lucy (Australopithecus afarensis), 3.2meterone year old fossil skeleton discovered in 1974 in Ethiopia. You called him Kenyanthropus platyops: the flat-faced man from Kenya. How did that change our understanding of evolution?
Lucy received a great deal of publicity. She was always projected as the common ancestor of humans. I always felt like it didn’t make sense, because if you looked at any other animal lineage, there were always so many species. I thought: there must be diversity [in the early hominins].

When we found this specimen, it was crushed and broken, so it took a long time to make sense of it. But you could tell that it was something completely new and different from Lucy. He lived contemporaneously with Lucy, but she had this really flat face. The meaning was powerful: it showed Lucy it was not necessarily the ancestor of all later hominids.

His book does not include a family tree of our origins. Was that deliberate?
Yes. I tend not to try to draw straight lines between things. Much more remains to be discovered. I am concerned that, rather than contributing to our understanding, lineage building may only be preliminary and may in fact be misleading.

There are periodic attempts to discredit Africa as the “birthplace of mankind.” How have things changed throughout your career? And should East Africa or Southern Africa, where fossils of early hominids have also been found in caves, do you understand the nickname?
Early paleontologists did not believe that humans could have come from Africa. Humans must have originated in Europe, it was prejudiced. The work to convince the scientific community and the world otherwise was started by my in-laws and continued by my husband, myself, and daughter Louise. As I have progressed in my career, it has become more and more accepted. Africa is definitely where it all started. The climate and vegetation were adequate. And, for me, it’s most likely East Africa, because if you look at where non-human primates are distributed today, they are concentrated in the tropics and the equator.

How do we evolve our tremendous brain power and our ability to walk on two legs??
Evolution occurs due to changing habitats driven by climate change. Driven by a drought trend, towards a more open savanna, I suspect our ancestors began to descend from the trees to the ground. They found that if they stood on two legs they could better reach food, such as berries and fruits in the bushes, and could travel further.

Big brains came later, after bipedalism and increased dexterity. Brains are expensive in terms of calories. To develop a big brain, you must have a good source of food. When our ancestors began to find a way to hunt and capture a lot of meat, they were able to develop larger brains.

Donated a kidney to Richard, and helped him lose both legs in a plane crash. Do you think our ancestors formed similar social ties?
I’m sure. We found a 1.6 million year old femur [thigh bone] that was clearly broken and fixed, and that could only have meant that the individual was cared for. Otherwise they would not have succeeded. The degree of social connection must have been considerable.

Are you still digging and what would be your ultimate find?
I still go into the field, but not that much. Louise and I have an amazing team, so we don’t have to be there all the time. We work primarily on the west side of Lake Turkana, reviewing 4 million-year-old sites that we worked on decades ago. Fossils wear out all the time, so you can find many more. Finding a complete skeleton of any primitive hominid is my dream. We can learn much more than just from a skull.

Are we still evolving?
I don’t think we are still physically evolving, because we control our environment a lot. And while there is climate change now, which means that we cannot live in the places where we live today, it is hard to imagine that it will affect our physical evolution due to that control. However, our technology is evolving fantastically. Our evolution is now more technological than morphological.

The sediments of time: my search for the past throughout my life by Meave Leakey is published by Houghton Mifflin Harcourt (£ 23.99). To order a copy, go to guardianbookshop.com. Shipping charges may apply

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